Jul. 12, 2019 Contents · Jul. 12, 2019 China MEE released a comprehensive plan to strengthen the management of VOCs in key in-dustries. The plan describes the current situation and

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Contents(click on page numbers for links)

REGULATORY UPDATE

ASIA PACIFICIMAP Tranche 27 ................................................................................................................4Provide feedback on the recommendations of the 2018 review of the model WHS laws ........................................................................................................4Proposal to update the GHS under the model WHS laws – consultation now open ...................................................................................................5MEE Releases Comprehensive Management Plan for VOCs in Key Industries ..............................................................................................................................6Vietnam to Establish National Operation Centre Tasked with Elimination of Toxic Chemical Hazards ......................................................................7

AMERICANotice of Modification to Text of Proposed Regulation: Proposed Amendment to Sections 25821(a) and (c) level of Exposure to Chemicals Causing Reproductive Toxicity: Calculating Intake by the Average Consumer of a Product ..................................................................................8EPA Evaluates Risk from Electric Power Facilities and Proposes No Additional Federal Requirements ................................................................................9uS EPA finds little risk in latest chemical assessments .......................................10States sue uS EPA for failure to act on asbestos ...................................................11DA Issues Prescription labelling Draft Guidance ................................................12Health Canada Issues New Reporting Requirements for Hospitals ..............13

EUROPEThe Scientific Committee on Consumer Safety plays a vital role in the Commission’s ongoing work on Endocrine Disruptors .............................13EC Requests Scientific Opinions on Hydroxyapatite (Nano) and Nano Copper and Colloidal Copper .........................................................................15Guidance on bees and pesticides: work plan published ..................................16

REACH UPDATEECHA to scrutinise all REACH registrations by 2027 ...........................................17Cefic launches Action Plan to help REACH registrants review chemical safety data .......................................................................................................18

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ContentsManagement Board supports efforts to improve REACH authorisation and evaluation ......................................................................................19Enforcement Forum: inspectors to look into classification of mixtures ......20Authorisations granted for uses of three substances.........................................21

JANET’S CORNERChemist’s Dog ...................................................................................................................22

HAZARD ALERTHeptachlor .........................................................................................................................23

GOSSIPOne-two-punch catalysts trapping CO2 for cleaner fuels ................................29Baby Steps Forward: Recommendations for Better understanding Environmental Chemicals in Breast Milk and Infant Formula .........................30Quantum physics experiment shows Heisenberg was right about uncertainty, in a certain sense ....................................................................................33‘Virtual Biopsy’ Device Detects Skin Tumours In 15 Minutes ...........................35light-powered nano-organisms consume carbon dioxide, create eco-friendly plastics and fuels ....................................................................................36Materials informatics reveals new class of super-hard alloys ..........................38Carbon-neutral fuels move a step closer ................................................................40Revealing ‘hidden’ phases of matter through the power of light ..................41Researchers take two steps toward green fuel .....................................................42Research reveals liquid gold on the nanoscale ....................................................43Semi-liquid metal anode for next-generation batteries ...................................44Bacteria such as E. coli detected in minutes by new tech ................................46Electric vehicles would be a breath of fresh air for Houston ...........................47A metal-free, sustainable approach to carbon dioxide reduction .................48Researchers report efficient platform technology for producing cephalosporin antibiotics .............................................................................................49Household Ingredients Rich in Sodium Help Grow Carbon Nanotubes .....51Superconducting magnet breaks strength world record .................................53Consequences of Deepwater Horizon oil spill ......................................................54

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ContentsCURIOSITIES

Chemists’ breakthrough in synthesis advances a potent anti-cancer agent ....................................................................................................................................56Drinking alcohol at conception shown to harm rats – new study ................58Is the Radiation from Airport Body Scanners Dangerous? ...............................59What Are ‘Forever Chemicals’ And How Are They Getting in Your Food? ....61Hyped-up science is a problem. One clever Twitter account is pushing back. ...................................................................................................................64Processed foods are a much bigger health problem than we thought ......65Many breakfast cereals still contaminated by weed killer, environmental group says ...........................................................................................71DDT still affecting lake ecosystems 50 years after it was banned ..................74Tackle scourge of indoor air pollution, doctors urge .........................................75Steffanie Strathdee: ‘Phages have evolved to become perfect predators of bacteria’ .....................................................................................................76Mercury-level high in marine foods sourced near coal-fired plants .............80How many steps a day do you really need? Spoiler: It isn’t 10,000 ...............81

TECHNICAL NOTES(Note: Open your Web Browser and click on Heading to link to section) ...87ENVIRONMENTAl RESEARCH ......................................................................................87MEDICAl RESEARCH .......................................................................................................87OCCuPATIONAl RESEARCH .........................................................................................87PuBlIC HEAlTH RESEARCH ..........................................................................................88

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On 28 June 2019, the National Industrial Chemicals Notification & Assessment Scheme (NICNAS) published IMAP Tranche 27.

ASIA PACIFIC

IMAP Tranche 272019-06-28On 28 June 2019, the National Industrial Chemicals Notification & Assessment Scheme (NICNAS) published IMAP Tranche 27. Interested parties are invited to comment on the assessment outcomes of IMAP – Tranche 27 reports. The public comment period closes on 23 August 2019. NICNAS established the Inventory Multi-tiered Assessment and Prioritisation (IMAP) framework to accelerate the assessment of existing chemicals on the Australian Inventory of Chemical Substances(AICS or the Inventory). IMAP is a scientific and risk-based model for assessing chemicals with three tiers of assessment. The assessment effort increases with each tier. A decision is made at the end of each assessment tier if the next tier of assessment is required to determine risk. The risk assessments for human health and environment have been conducted separately and may have different outcomes and be published separately. The assessment outcomes are based on the information available at the time. Chemicals assessed using the IMAP framework have been published in reports over several tranches.

NICNAS, 28 June 2019

http://www.nicnas.gov.au

Provide feedback on the recommendations of the 2018 review of the model WHS laws2019-07-08The model WHS laws were reviewed in 2018. The Review of the model WHS laws: Final report was released in February 2019 and includes 34 recommendations. A Consultation Regulation Impact Statement (RIS) on these recommendations is now open. Submissions can be made online. Safe Work Australia welcomes feedback and comments from all stakeholders who may be impacted by the recommendations. The agency is particularly interested in feedback on the review recommendations that may have the greatest impact on workers, business and the community, including:

• introducing regulations dealing with psychosocial health;• new arrangements for health and safety representatives (HSR) and

work groups in small businesses;

Regulatory Update

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Regulatory Update• clarifying workplace entry of HSR assistants and WHS entry permit

holders;• providing HSRs with choice of training course;• providing a process for resolving disputes about WHS issues;• including gross negligence as an element of the Category 1 offence;

and• introducing an industrial manslaughter offence.Safe Work Australia has set up a consultation page with information and details on how you can participate.

Safe Work Australia, 1 July 2019

http://www.safeworkaustralia.gov.au

Proposal to update the GHS under the model WHS laws – consultation now open2019-07-08Safe Work Australia invites interested stakeholders to share their feedback via our online consultation page, Engage on adopting an updated edition of the Globally Harmonised System of Classification and labelling of Chemicals (GHS) under the model Work Health and Safety (WHS) laws. Since 1 January 2017, the 3rd revised edition of the GHS (GHS 3) has been implemented for workplace hazardous chemicals. As Australia’s transition to the GHS is now complete, it is time to move beyond GHS 3 to ensure Australia’s classification and labelling requirements for workplace chemicals are aligned with our key trading partners, as they move to the 7th revised edition of the GHS (GHS 7). Safe Work Australia welcomes feedback from manufacturers, importers, suppliers, users and other stakeholders that have an interest in hazardous chemicals in the workplace, about moving from GHS 3 to GHS 7. A Consultation Paper has been prepared which outlines the key changes from GHS 3 to GHS 7 and the particular topics we would like to receive feedback on. To provide your feedback and to access the Consultation Paper, register to our consultation platform, Engage. The consultation will close 28 July 2019.

Safe Work Australia, 3 July 2019

http://www.safeworkaustralia.gov.au

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Jul. 12, 2019

China MEE released a comprehensive plan to strengthen the management of VOCs in key in-dustries. The plan describes the current situation and existing problems of China’s VOCs governance in detail and points out management goals and methods.

Regulatory UpdateMEE Releases Comprehensive Management Plan for VOCs in Key Industries2019-07-08On 26 June 2019, China Ministry of Environment and Ecology (MEE) released the Comprehensive Management Plan for Volatile Organic Compounds in Key Industries to strengthen the guidance on governance of VOCs. Recently, China issued several national standards to complete the management of VOCs. In particular, they provide more detailed regulations on VOCs emissions in some key industries. According to the MEE research, the emission of VOCs has become a major source of atmospheric and environmental pollution. VOCs are important precursors in the formation of PM2.5 particulates and ozone (O3). The new comprehensive management plan is expected to improve pollution control of VOCs in key industries and in key regions. Five major problems in the management of VOCs are pointed out in the plan, they are:

1. Insufficient source control2. Fugitive emission3. Simple and inefficient pollution control facilities4. Non-standard operation management5. Inadequate monitoringTo deal with these problems, the plan provides the targeted control methods and requirements for major governance industries such as petrochemical, coating, packaging and printing, oil storage and gas station. The improvement of the overall treatment of VOCs in industrial parks is also mentioned in the plan, as well as the supervisory responsibilities of the relevant government departments in this operation. The five annexes of the program introduce the major monitoring areas, focused VOCs substances, as well as the requirements for record keeping, industrial enterprises governance points and the petroleum products storage, transportation and sales governance points. The main focuses of the entire process of VOCs emission from the source to the disposal are reflected in the last three annexes. Further information is available at: MEE Notice

Chemlinked, 5 July 2019

http://chemlinked.com/en/news

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Vietnam’s Prime Minister, Nguyen Xuan Phuc recently decided to establish a national operation centre for eliminating toxic chemical hazards and minimising envi-ronmental accidents.

Regulatory UpdateVietnam to Establish National Operation Centre Tasked with Elimination of Toxic Chemical Hazards2019-07-08Vietnam’s Prime Minister, Nguyen Xuan Phuc recently decided to establish a national operation centre for eliminating toxic chemical hazards and minimising environmental accidents. Part of the plan includes improving the Environment Management and Technical Centre affiliated with the Chemical Headquarters of Ministry of National Defence. The Prime Minister requires the Ministry of National Defence to help Chemical Headquarters manage the national operation centre. The Ministry of National Defence is also responsible for the activities conducted by the national operation centre and ensuring the effective execution of various activities.

The Responsibilities of National Operation Centre

• Responsible for hosting activities and cooperation with other related departments to eliminate impacts created by toxic chemical hazards in human health and environment after The Vietnam War, and reducing the occurrence of accidents involving hazardous and toxic chemicals and radioactive materials.

• Responsible for creating and managing an information database related to eliminating toxic chemical hazards after The Vietnam War.

• Responsible for conducting scientific research and technical transfer activities. Responsible for implementing relevant plans with related departments and improving staff’s capabilities.

Further information is available at: Vietnam+

Chemlinked, 5 July 2019

http://chemlinked.com/en/news

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California’s Office of Environmental Health Hazard Assessment (OEHHA) is providing notice of changes to the proposed regula-tory action to amend Sections 25821(a) and 25821(c) of Title 27 of the California Code of Regulations.

Regulatory UpdateAMERICA

Notice of Modification to Text of Proposed Regulation: Proposed Amendment to Sections 25821(a) and (c) Level of Exposure to Chemicals Causing Reproductive Toxicity: Calculating Intake by the Average Consumer of a Product2019-07-08California’s Office of Environmental Health Hazard Assessment (OEHHA) is providing notice of changes to the proposed regulatory action to amend Sections 25821(a) and 25821(c) of Title 27 of the California Code of Regulations. Section 25821 addresses calculating the level of exposure to chemicals listed under Proposition 65 as known to cause reproductive toxicity. The proposed regulation was originally the subject of a Notice of Proposed Rulemaking published on 5 October 2018, in the California Regulatory Notice Register (Register No. Z2018-0925-07), which initiated a 45-day public comment period. A public hearing was held on 19 November 2018. OEHHA received oral comments from four commenters. The California Chamber of Commerce and the Grocery Manufacturers Association requested an extension of the comment period, which OEHHA granted. Ten written comments were received during the extended comment period that ended 3 December 2018. After carefully reviewing the comments received, OEHHA has modified the proposed regulation in Section 25821(a) to state that the concentration of a listed chemical in a food product may be based on the concentration in the product as it is offered for sale to the end consumer, even if the product contains ingredients sourced from different manufacturers or producers. For example, where grains are harvested from multiple farms and are then mixed together at a manufacturing facility, the concentration of a listed chemical in the mixture can be measured in the finished product as it is offered for sale to the consumer (i.e., in a bag, box or other container). In addition, OEHHA is not proceeding at this time with the amendment to Section 25821(c)(2), which would have established the arithmetic mean as a default in calculating the reasonably anticipated rate of intake or exposure for average users of a consumer product. Therefore, OEHHA is no longer proposing a change to Section 25821(c)(2) as part of this rulemaking. The full regulatory text with the modified language provided in double underline and double strikeout format is available on request from Monet Vela in the OEHHA legal Office. OEHHA is requesting comments on the modifications to the regulatory text. In order to be

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The United States Environmental Protec-tion Agency (EPA) recently announced that it finds that the risk from Electric Power Generation, Transmission and Distribution facilities does not warrant fi-nancial responsibility requirements to cover the costs of possible hazardous substance releases due in part to the existing state and federal requirements on these facilities.

Regulatory Updateconsidered, OEHHA must receive comments by 22 July 2019, which is the designated close of the comment period. All comments will be posted on the OEHHA website at the close of the public comment period. Further information is available at: Comment Submissions - Notice of Modification to Text of Proposed Amendments to Sections 25821(a) and (c) level of Exposure to Chemicals Causing Reproductive Toxicity: Calculating Intake by the Average Consumer of a Product

OEHHA, 5 July 2019

http://www.oehha.ca.gov

EPA Evaluates Risk from Electric Power Facilities and Proposes No Additional Federal Requirements2019-07-08The united States Environmental Protection Agency (EPA) recently announced that it finds that the risk from Electric Power Generation, Transmission and Distribution facilities does not warrant financial responsibility requirements to cover the costs of possible hazardous substance releases due in part to the existing state and federal requirements on these facilities. using the authority of the Comprehensive Environmental Response, Compensation, and liability Act (CERClA) Section 108(b), EPA analysed the need for financial responsibility requirements for the electric power industry. The evaluation was based on the degree and duration of risk associated with the production, transportation, treatment, storage or disposal of hazardous substances in the industry. After completing its analyses, the agency concluded that the level of risk does not warrant financial responsibility requirements for this sector. This reflects EPA’s interpretation of the statute and EPA’s evaluation of the record for this proposed rule. “After careful analysis, EPA believes that modern industry practices, along with existing state and federal regulations, address risks from operating electric power facilities and, therefore, CERClA financial responsibility requirements are unwarranted,” said EPA Administrator Andrew Wheeler. “By proposing no new financial requirements, we will be ensuring that no duplicative or unnecessary burdens fall on America’s energy producers.” Section 108(b) of CERClA (also known as Superfund) directs EPA to develop regulations requiring classes of facilities to establish and maintain evidence of financial responsibility to cover the costs associated with releases or threatened releases of hazardous substances from their facilities. The proposal will be published in the Federal Register, and EPA invites stakeholders and the public to provide comments during a 60-day public comment

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Agency ignores past contamina-tion, focuses on narrow set of uses

Regulatory Updateperiod. EPA is under a court-ordered deadline to take final action on this rulemaking by December 2, 2020. The agency is also working toward court-ordered deadlines for rulemakings addressing CERClA 108(b) financial responsibility for two additional industries: Chemical Manufacturing, and Petroleum and Coal Products Manufacturing. For more information, visit: https://www.epa.gov/superfund/superfund-financial-responsibility#ElectricPower.

u.S EPA, 2 July 2019

http://www.epa.gov

US EPA finds little risk in latest chemical assessments2019-07-08A group of cyclic aliphatic bromide flame retardants does not pose “an unreasonable risk of injury to the environment” or to people, the uS Environmental Protection Agency concludes in a draft risk evaluation released 28 June 2019. The substances, found in insulated construction materials and automobile replacement parts, include hexabromocyclododecane (HBCD) and similar chemicals that the EPA claims are no longer manufactured or imported in the uS. In a separate evaluation for the industrial solvent 1,4-dioxane, the EPA finds the potential for unreasonable risks to workers in certain situations. However, the agency will likely defer to the Occupational Safety and Health Administration to regulate such risks, just as it is doing with new chemicals entering the market that pose risks to workers. The EPA did not identify any consumer uses of 1,4-dioxane, even though the chemical is an impurity in ethoxylated compounds found in some detergents and shampoos. “Such activities will be considered in the scope of the risk evaluation for ethoxylated chemicals,” the EPA says. 1,4-dioxane also contaminates drinking water from public utilities in 27 uS states, serving more than 7 million people, according to a 2017 report by the Environmental Working Group, an advocacy group. The EPA considers 1,4-dioxane “likely to be carcinogenic to humans.” The two evaluations are part of the first group of 10 that the EPA is conducting to determine the potential risks of chemicals to human health and the environment under the 2016 revisions to the Toxic Substances Control Act. The two draft assessments are the second and third of the 10 to be released for public comment by the EPA. The agency must finalize all 10 by the end of the year. In the first evaluation, which was released in November, the agency found no unreasonable risks associated with use of Pigment Violet 29, a colorant used in inks, paints, coatings, and plastics. A panel of experts and several environmental

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A coalition of 11 state attorneys general is taking the United States Environmental Protection Agency to court following the agency’s denial of a petition seeking an asbestos regulation.

Regulatory Updategroups have criticised that assessment for making the determination with insufficient data. A group of Democrats in the Senate is also raising concerns that the EPA’s chemicals program is ignoring its responsibility to protect workers and leaving it up to other agencies or offices within the EPA to regulate chemical exposures in air, water, or food. The EPA is required to protect vulnerable populations, including children, pregnant women, the elderly, and industrial workers, under the amended TSCA. In a June 20 letter to EPA administrator Andrew Wheeler, those senators claim that the EPA’s implementation of TSCA has “deviated dramatically from Congress’ intent and the new law’s requirements.” The latest two draft assessments, like the one for Pigment Violet 29, show a pattern of finding no risks associated with a narrowly defined set of a chemical’s uses. Those uses do not include contamination from past uses. The EPA is accepting comments on the two draft assessments for 60 days. A group of outside experts will review the documents at a July 29–Aug. 2 meeting.

Chemical & Engineering News, 28 June 2019

http://pubs.acs.org/cen/news

States sue US EPA for failure to act on asbestos2019-07-08A coalition of 11 state attorneys general is taking the united States Environmental Protection Agency to court following the agency’s denial of a petition seeking an asbestos regulation. The petition, which the states filed in January, asked the EPA to require companies to report their importation and use of asbestos in the uS. The states asserted that the agency needs such data to prevent unreasonable risks to people and the environment posed by asbestos, a known human carcinogen. The agency denied the states’ petition in April. The EPA must finish its evaluation of the risks of asbestos under the revised Toxic Substances Control Act (TSCA) by the end of the year. Asbestos “kills tens of thousands of people every year, yet the Trump Administration is choosing to ignore the very serious health risks it poses,” Massachusetts attorney general Maura Healey says in a statement. Healey and several state attorneys general previously sent comments to the EPA opposing how the agency is conducting risk evaluations for asbestos and other high-priority substances under TSCA. The attorneys general claim the EPA refuses to consider some significant exposures.

Chemical & Engineering News, 28 June 2019

http://pubs.acs.org/cen/news

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The draft guidance will help ensure the information in prod-uct labelling on abuse, misuse, addiction, physical dependence and tolerance is clear, concise, useful, and informative.

Regulatory UpdateDA Issues Prescription Labelling Draft Guidance2019-07-08The u.S. Food & Drug Administration has issued new draft guidance on labelling for prescription medicines. Titled “Drug Abuse and Dependence Section of labelling for Human Prescription Drug and Biological Products - Content and Format,” the draft contains recommendations that represent FDA’s current thinking on the content and format of this section for prescription medications that are scheduled under the Controlled Substances Act, as well as for prescription medications not scheduled under the CSA for which there is important information to convey to health care professionals related to abuse and dependence. “Our goal is that this guidance will help ensure that information in product labelling on abuse, misuse, addiction, physical dependence and tolerance is clear, concise, useful and informative,” the agency’s news release states. For example, the draft guidance recommends that terminology used in the Drug Abuse and Dependence section – such as abuse, misuse, addiction, physical dependence, and tolerance – be defined in labelling to ensure common understanding, and FDA has included recommended definitions. The guidance says that a person who takes a friend’s prescription opioid medication to relieve tooth pain is misusing the medication; if that person takes a friend’s opioid to get a euphoric high, that use represents abuse of the medication. A second draft guidance announced July 1, “Instructions for use — Patient labelling for Human Prescription Drug and Biological Products and Drug-Device and Biologic-Device Combination Products — Content and Format,” relates to how the drug or biologic is used. Instructions for use (IFu) is a type of labelling for patients who use products that have complicated or detailed patient-use instructions; it offers detailed, action-oriented, step-by-step written and visual instructions in a patient-friendly manner and typically includes instructions on preparation, administration, handling, storage, and disposal. The recommendations in the IFu guidance are intended to promote development of consistent content and format across IFus.

Occupational Health & Safety, 2 July 2019

http://www.ohsonline.com

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To address potential risks for human health, the cosmetic products regulation (Regulation (EC) N 1223/2009) lays down a system of restrictions and bans on the use of certain substances in cosmetics based on a scientific risk assessment carried out by the Scientific Committee on Con-sumer Safety (SCCS).

Regulatory UpdateHealth Canada Issues New Reporting Requirements for Hospitals2019-07-08New regulations that apply to hospitals in Canada will require them to report serious adverse drug reactions and medical device incidents to Health Canada within 30 days after the incidents are documented within the institutions. Announced 26 June, the regulations will take effect in late 2019. Health Canada’s news release announcing the new regulations note that drugs and medical devices are an important part of Canada’s health care system, adding that serious adverse drug reactions and medical device incidents are significantly under-reported, both in Canada and internationally. Ginette Petitpas Taylor, Canada’s minister of Health, announced the regulations, saying they will improve the quality and increase the number of reports Health Canada receives on these incidents, allowing the department to better monitor the safety of drugs and devices on the market. The regulations are part of Health Canada’s Action Plan on Medical Devices, which was announced in December 2018.

Occupational Health & Safety, 27 June 2019

http://www.ohsonline.com

EUROPE

The Scientific Committee on Consumer Safety plays a vital role in the Commission’s ongoing work on Endocrine Disruptors2019-07-08To address potential risks for human health, the cosmetic products regulation (Regulation (EC) N 1223/2009) lays down a system of restrictions and bans on the use of certain substances in cosmetics based on a scientific risk assessment carried out by the Scientific Committee on Consumer Safety (SCCS). Scientific concerns about the endocrine-disrupting properties of substances used in cosmetic products are, like other substances of concern for human health, addressed in the risk assessment of the SCCS. Endocrine disruptors are chemical substances that can alter the functioning of the endocrine (hormonal) system and negatively affect the health of humans or animals. Conclusions are made on whether endocrine/hormonal activities are linked to the critical endpoint for assessing the safety of these substances for consumers,

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Regulatory Updateincluding vulnerable groups such as children when applicable. On 7 November 2018, the Commission adopted the review of Regulation (EC) No 1223/2009 on cosmetic products regarding substances with endocrine-disrupting properties. The report took stock of how substances considered as potential endocrine disruptors were tackled under the cosmetics regulation – namely, banned or restricted on a case-by-case basis following their safety assessment by the SCCS. The overall conclusion is that the cosmetic regulation provides the adequate tools to regulate the use of cosmetic substances that present a potential risk for human health. The Commission also committed to establishing a priority list of potential endocrine disruptors not already covered by the bans in the cosmetics regulation by the end of March 2019 for risk assessment. The starting point for this priority list was the result of the screening study that was conducted to support the impact assessment in the field of plant protection products and biocides. The screening study identified 6 substances (benzophenone-3, kojic acid, 4-methylbenzylidene camphor, propylparaben, triclosan and resorcinol) used in cosmetic products as potentially having endocrine-disrupting properties that were not covered by an existing or ongoing prohibition. The Commission presented the preliminary list to the working group on cosmetic products in December 2018. Working group members were invited to comment on the list and submit other substances of concern considered as potential endocrine disruptors along with argumentation for this consideration. Following working group members’ input, a final list of 28 substances was consolidated and split into two groups. ‘Group A’ consists of 14 substances deemed as a higher priority for assessment as they are undergoing substance evaluation under REACH for endocrine disruptors concerns or the scientific evidence has already confirmed endocrine disruptors concerns. Group B consists of 14 substances where either no scientific evidence has been initiated or the outcome of the scientific evidence is of an environmental endocrine disruptors concern and not a human health one. Group B also contains substances that have recently been evaluated by the SCCS and found safe, and/or Substances that have been recently classified as Carcinogenic, Mutagenic and Reprotoxic substances under Classification, labelling and Packaging of substances and mixtures where corresponding risk assessment/management measures are in place to prohibit/restrict their use in cosmetic products. A first call for data related to the 14 substances found in Group A has been launched. upon receipt of sufficient data, the Commission will mandate the SCCS to evaluate the substances as soon as possible. If needed, the Commission will then take appropriate action to prohibit or restrict the use of the different substances in cosmetics. Additional calls for data related to the

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Regulatory Update14 substances found in Group B are planned for the future, taking into consideration any relevant developments. Further information is available at: Read more about the work of DG GROW on cosmetics

Eu Scientific Committees, 4 July 2019

http://ec.europa.eu/health/scientific_committees/index_en.htm

EC Requests Scientific Opinions on Hydroxyapatite (Nano) and Nano Copper and Colloidal Copper2019-07-08On 25 June 2019, the European Commission’s (EC) Scientific Committee on Consumer Safety (SCCS) posted two requests for scientific opinions: hydroxyapatite (nano) and copper (nano) and colloidal copper (nano). According to the mandate for hydroxyapatite (nano), the EC received 17 notifications for cosmetic products containing hydroxyapatite in nano form. The EC states that according to the notifications, this ingredient is used in both leave-on and rinse-off dermal and oral cosmetic products, including skin (skin care) and oral hygiene (toothpaste, mouthwash) products, with different concentration and specifications.  The EC has concerns about the use of hydroxyapatite in nano form “because of the potential for nanoparticles to be absorbed dermally or across a mucous membrane and to enter cells.” It requests SCCS carry out a safety assessment of the nano form of hydroxyapatite as reported in the notifications. According to the mandate for copper (nano) and colloidal copper (nano), the EC received 36 notifications for cosmetic products containing copper (31 notifications) and colloidal copper (five notifications) in nano form. According to the notifications submitted, both ingredients are used in nano form in leave-on and rinse-off cosmetic products, including skin, nail and cuticle, hair and scalp, and oral hygiene products with different concentration and specifications. The EC states that it has concerns on the use of copper and colloidal copper in nano form “because of the potential for nanoparticles to be absorbed dermally or across a mucous membrane and to enter cells.”  It requests SCCS carry out a safety assessment of the nano form of copper and colloidal copper reported in the notifications.

Nano & Other Emerging Technologies, 2 July 2019

http://nanotech.lawbc.com

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Jul. 12, 2019

The European Food Safety Authority (EFSA) has outlined how it plans to review its guidance on the risk assessment of pesticides and bees in the EU.

Regulatory UpdateGuidance on bees and pesticides: work plan published2019-07-08The European Food Safety Authority (EFSA) has outlined how it plans to review its guidance on the risk assessment of pesticides and bees in the Eu. As the outline shows, stakeholders and pesticide experts from Member States will be consulted regularly throughout the process. The first consultation begins later this month, when stakeholders and Member State representatives will be asked for their views on the current guidance document. Stakeholder feedback will be provided by a consultation group, comprising representatives of EFSA’s different stakeholder communities, that has been set up to support the revision of the guidance. Member States will be consulted through EFSA’s existing Pesticides Steering Network. Gathering views on the existing guidance, published in 2013, is an important first step in EFSA’s review as highlighted in the mandate received from the European Commission. When the feedback has been gathered and analysed, EFSA’s scientific working group will begin its review. A full public consultation and workshop will take place when the document has been drafted. Outline of the revision of the guidance on the risk assessment of plant protection products and bees

EFSA, 5 July 2019

http://www.efsa.europa.eu

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The European Chemi-cals Agency (ECHA) will start to evaluate 20% of registration dossiers in each ton-nage band to improve the compliance of REACH registrations.

ECHA to scrutinise all REACH registrations by 20272019-07-08The European Chemicals Agency (ECHA) will start to evaluate 20% of registration dossiers in each tonnage band to improve the compliance of REACH registrations. This will mean approximately 30 % of all registered chemicals will be checked. The Commission will propose an amendment to REACH to raise the current 5% minimum target for compliance checks to 20% of registration dossiers in each tonnage band. This means checks for about 30% of all registered substances. The increased target is part of ECHA and the Commission’s joint action plan to address the lack of compliance in registration dossiers and encourage industry to improve their safety data on chemicals. Bjorn Hansen, ECHA’s Executive Director says: “Improving compliance with the law is our key priority for the coming years. REACH data is the basis of the European union’s whole chemicals management system. Together with the Commission and Member States, we are committed to putting these concrete measures in place to address non-compliance and improve chemicals safety in Europe. To achieve this, we will also need a strong commitment from European industry to increase their efforts under REACH.” ECHA’s aim is to screen all registration dossiers submitted by the 2018 deadline: by 2023 for substances registered over 100 tonnes per year and by 2027 for substances in the tonnage band 1-100 tonnes per year. The agency will also check the compliance of at least 30 % of substances, making sure that this check is done for all substances where more information is needed. These include, for example, substances with hazardous properties, or where more data needs to be generated to conclude a potential risk. Similar substances will be assessed in groups to gain efficiency and ensure that proposals for further regulatory action are consistent. For high tonnage substances, ECHA will conclude by the end of 2020 whether they are a priority for risk management, for data generation or currently of low priority for further action. To meet these ambitious targets, ECHA will re-allocate staff from other functions to evaluation tasks. Other actions include simplifying compliance check decisions, increasing enforcement, interaction with industry associations to make sure registrants step up their compliance efforts, and establishing a transparent monitoring system of the progress made. Further information is available at:

• REACH Evaluation Joint Action Plan• Annual evaluation reports• Recommendations to registrants

REACH Update

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In June 2019 the European chemical industry launched an unprecedented action to proactively and systematically review and update data in previously submitted REACH registration dossiers.

REACH Update• REACH reviewECHA, 24 June 2019

http://echa.europa.eu

Cefic launches Action Plan to help REACH registrants review chemical safety data2019-07-08In June 2019 the European chemical industry launched an unprecedented action to proactively and systematically review and update data in previously submitted REACH registration dossiers. This initiative comes in response to the recent conclusion by the European Chemicals Agency (ECHA) that many REACH registration dossiers require additional information. To this end Cefic has developed a multi-annual Action Plan, which provides a framework for REACH registrants to evaluate the safety data in a stepwise manner. The Action Plan outlines the timeline, roles and responsibilities, substance prioritisation criteria, critical issues, and explains how progress will be reported. The goal of the Action Plan is to achieve a better alignment between the data that have been submitted in good faith by registrants and ECHA’s current expectations on the content of dossiers. Since there is no ‘perfect REACH dossier’ template and every case are different, the Action Plan will be implemented in cooperation with ECHA. The Action Plan Package consists of the following elements:

• Declaration of Intent: signed by individual companies, whereby companies express their intent to re-evaluate dossiers and to provide further information, where appropriate, in line with the Action Plan. Companies also commit to report to Cefic on KPIs so that Cefic can report on progress on an annual basis. To that effect, a reporting template has been developed.

• Cooperation Agreement between Cefic and ECHA: outlines a series of specific activities to support the implementation of this Action Plan and guide registrants to a better understanding of how to meet ECHA’s expectations under Article 41 of REACH (‘Compliance Check’). The Action Plan will run between 2019-2026, allowing for one year of planning and setting-up and seven years of actual updates.

All Cefic Board members have already committed to this Action Plan. All Cefic member companies and national association (Member / Partner federations) members are also encouraged to sign the Declaration of Intent. Cefic does not have access to registration dossiers, and all updates will be done by individual companies. However, Cefic will facilitate

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The European Chemi-cals Agency’s (ECHA) Management Board has expressed its con-fidence in the plans to adjust the process for applications for authorisation.

REACH Updatethe support and development of tools and solutions for cross-cutting, unresolved key issues related to registration dossiers. The Action Plan is not a static document; it will be adapted to developments when and if needed.

CEFIC, 26 June 2019

http://www.cefic.org</

Management Board supports efforts to improve REACH authorisation and evaluation2019-07-08The European Chemicals Agency’s (ECHA) Management Board has expressed its confidence in the plans to adjust the process for applications for authorisation. The Board also welcomed the joint action plan of ECHA and the European Commission to improve the compliance of REACH registrations. “ECHA is investing a lot to improve these two critical processes for the future of REACH, in line with the recommendations of the second Commission review of REACH. For applications for authorisation, it has duly considered the recent Court cases, listened to the European Parliament and other stakeholders and taken their feedback seriously. As for REACH evaluation, the joint action plan paves the way to address the lack of compliance of many registration dossiers,” says Sharon McGuinness, the Chair of ECHA’s Management Board. ECHA’s work on authorisation will be improved in three ways: Firstly, ECHA’s formats for applications for authorisation will require applicants to provide a substitution plan in their application if there are suitable alternatives available in general but they are not yet feasible for the applicant. Secondly, ECHA will revise the opinion formats used by its scientific Committees for Risk Assessment (RAC) and for Socio-economic Analysis (SEAC). This is expected to also clarify the boundaries between scientific opinion making by ECHA’s committees and the decisions by the Commission. Finally, ECHA will standardise the opinion texts to help rapporteurs build up more consistent and concise opinions. The Management Board also welcomed the joint evaluation action plan by ECHA and the Commission as “the right way to achieve a high degree of compliance with the legal requirements of REACH”. ECHA and the Commission will publish this plan early next week. “The Board encourages the Agency to continue to work with its stakeholders, further improve these key processes and take action where necessary. We will be looking forward to receiving information on the progress of these improvement actions”, Ms McGuinness adds.

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The Forum agreed to conduct a pilot project to check the classification of mixtures, including detergents and cleaning products.

REACH UpdateManagement Board documents will be available on the Agency’s website in due course. Further information is available at:

• June Management Board meeting’s agenda• More about the Management Board• Management Board meeting documents• REACH Review• Applications for authorisationECHA, 20 June 2019

http://echa.europa.eu

Enforcement Forum: inspectors to look into classification of mixtures2019-07-08The Forum agreed to conduct a pilot project to check the classification of mixtures, including detergents and cleaning products. It will also explore with ECHA’s stakeholders, whether they can take actions to improve safety data sheets at a meeting on 4 July 2019. The Forum agreed to organise a pilot project on ClP addressing the classification of mixtures. The pilot project will focus on detergents and cleaning products but other types of mixtures may also be covered in the scope. The timing for this project will be decided in November 2019. The Forum also discussed the impact of the REACH Evaluation Joint Action Plan on enforcement activities. The plan identifies a number of actions for ECHA and the European Commission which aim to help ECHA check the compliance of 20 % of dossiers in each tonnage band by 2027. Some of these actions address enforcement. For example, ECHA plans to inform inspectors about cases where companies fail to update their dossiers. Also, ECHA plans to prepare a compilation of measures available to inspectors in their Member States. This could be used by inspectors to address non-compliance with dossier evaluation and to explore if ECHA could further support enforcement authorities in taking action when there is misuse of the evaluation process. The Forum will work together with the ECHA Secretariat to see whether and how these actions can be implemented. A recent Forum report analysing 197 safety data sheets (SDS) identified a number of common deficiencies in key sections of the SDSs. The report also formulates a number of recommendations about how these deficiencies could be addressed. The Forum working group will meet and discuss the recommendations for stakeholders at a meeting on 4 July 2019. The aim will be to explore if there are any solutions which stakeholder organisations can implement to improve

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The European Com-mission has granted authorisations for three uses.

REACH UpdateSDS quality, with a view to presenting them at the Forum open session in November 2019. The Forum for exchange of information on enforcement met on 18-19 June 2019 and the Biocidal Products Regulation Subgroup (BPRS) met on 20 June 2019 in Helsinki. Further information is available at:

• Enforcement Forum• Forum Report on Improvement of Quality of Safety Data Sheets• Notification of substances in articles• REACH Evaluation Joint Action PlanECHA, 25 June 2019

http://echa.europa.eu

Authorisations granted for uses of three substances2019-07-08The European Commission has granted authorisations for three uses. Review period expiration dates are in brackets:

• one use of arsenic acid (EC 231-901-9, CAS 7778-39-4) - Circuit Foil luxembourg SARl (22 August 2024);

• one use of bis(2-methoxyethyl) ether (EC 203-924-4, CAS 111-96-6) - N.V. Ajinomoto OmniChem S.A. (12 June 2026); and

• one use of sodium dichromate (EC 234-190-3, CAS 10588-01-9) - H&R Ölwerke Schindler GmbH; H&R Chemisch-Pharmazeutische Spezialitäten GmbH (12 June 2031).

Further information is available at:

Adopted opinions and previous consultations on applications for authorisation

ECHA News, 27 June 2019

http://echa.europa.eu

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Chemist’s Dog2019-07-07

Janet’s Corner

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Heptachlor2019-06-24

Heptachlor, chemical formula C10H5Cl7, is an organochlorine compound that was used as an insecticide. It is one of the cyclodiene insecticides. [1] Heptachlor is a white to light tan waxy solid with a camphor-like odour. It is insoluble in water and soluble in xylene, hexane, and alcohol. [2] Heptachlor was used extensively in the past for killing insects in homes, buildings, and on food crops. These uses stopped in 1988. [3] Due to its highly stable structure, heptachlor can persist in the environment for decades. [1] It is readily converted to more potent heptachlor epoxide once it enters the environment or the body. [4]

USES [5]

• Heptachlor is a constituent of technical grade chlordane, approximately 10 percent by weight.

• Heptachlor was used as an insecticide in the united States from 1953 to 1974. In 1974, nearly all registered uses of heptachlor were cancelled.

• Heptachlor was used from 1953 to 1974 as a soil and seed treatment to protect corn, small grains, and sorghum from pests. It was also used to control ants, cutworms, maggots, termites, and other pests in agriculture and in the home.

• Its sole u.S. manufacturer voluntarily cancelled the sale of heptachlor in 1987.

• In 1988, the sale, distribution, and shipment of existing stocks of all cancelled heptachlor and chlordane products were prohibited in the united States.

• The only commercial use of heptachlor products still permitted is fire ant control in power transformers. In addition, homeowner’s use of existing stocks of heptachlor-containing termite control products is also allowed.

IN THE ENVIRONMENT [6]

• When heptachlor is released into the environment it is converted to heptachlor epoxide, which degrades more slowly and is thus more persistent.

• Heptachlor partitions somewhat rapidly to the atmosphere from surface water and that volatilisation is significant.

Hazard Alert

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Hazard Alert• In contrast, heptachlor epoxide partitions slowly to the atmosphere

from surface water.• Heptachlor in water has an estimated half-life of 3.5 days.• Heptachlor epoxide has a half-life in water of at least 4 years.• Heptachlor and heptachlor epoxide adsorb strongly to sediments.• Temperature and humidity affect the persistence of heptachlor and

heptachlor epoxide in soil, as can the amount of organic matter present.

• Heptachlor and heptachlor epoxide are also taken up by plants and both may bioconcentrate in aquatic and terrestrial food chains.

SOURCES & ROUTES OF EXPOSURE

Sources of Exposure [5]

• People whose homes were treated for termites with heptachlor may be exposed to heptachlor in the indoor air for many years after treatment.

• Workers who use heptachlor to kill fire ants or who manufacture the chemical may be exposed to it in the air or through the skin.

• Heptachlor has been detected in food, including fish, shellfish, dairy products, meat, and poultry.

• Another possible source of exposure is drinking water; heptachlor has been detected at low concentrations in drinking water wells in several states.

Routes of Exposure [6]

• Inhalation – Minor route of exposure for the general population;• Oral – Primary route of exposure is through the diet;• Dermal – Minor route of exposure

HEALTH EFFECTS

Acute Effects

Acute inhalation exposure to heptachlor in humans has been associated with nervous system effects in a few case studies, while gastrointestinal effects, such as nausea and vomiting, have been reported to occur following accidental ingestion of heptachlor. Effects on the liver and central nervous system have been noted in animals acutely exposed to heptachlor via the oral route. Heptachlor is considered to have high to extreme acute toxicity based on short-term oral tests in rats.

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Hazard AlertChronic Effects

Chronic inhalation exposure to heptachlor has been associated with blood effects in humans, while oral exposure has resulted in neurological effects including irritability, salivation, dizziness, muscle tremors, and convulsions. Animal studies have reported effects on the liver, kidney, and the immune and nervous systems from oral exposure to heptachlor. The Reference Dose (RfD) for heptachlor is 0.0005 milligrams per kilogram body weight per day (mg/kg/d) based on liver weight increases in males rats only. EPA has not established a Reference Concentration (RfC) for heptachlor.

Reproductive/Developmental Effects

Heptachlor has been shown to cross the placenta to the developing foetus in humans. However, inadequate information is available to determine whether heptachlor may cause developmental or reproductive effects in humans. Animal studies have reported developmental effects, including foetal resorptions, and decreased postnatal survival, as well as reproductive effects such as failure of animals to reproduce, following oral exposure to heptachlor.

Cancer Risk

Human studies on heptachlor exposure and cancer are inconclusive. There are several case reports describing a possible link between heptachlor exposure and leukaemia and neuroblastoma; however, insufficient information is available to confirm a causal effect. Several studies on workers exposed via inhalation to heptachlor are available; however, these are limited due to confounding factors and small sample size. Animal studies have reported liver tumours in mice exposed to heptachlor via ingestion. EPA considers heptachlor to be a probable human carcinogen (cancer-causing agent) and has classified it as a Group B2 carcinogen.

SAFETY [7]

First Aid Measures

• Inhalation: Remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical attention immediately.

• Ingestion: If swallowed, give large quantities of water to drink and get medical attention immediately. Never give anything by mouth to an unconscious person.

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Hazard Alert• Skin Contact: Immediately flush skin with plenty of water for at

least 15 minutes while removing contaminated clothing and shoes. Get medical attention immediately. Wash clothing before reuse. Thoroughly clean shoes before reuse.

• Eye Contact: Immediately flush eyes with plenty of water for at least 15 minutes, lifting lower and upper eyelids occasionally. Get medical attention immediately.

Exposure Controls & Personal Protection [8]

Exposure Controls

Methods that are effective in controlling worker exposures to heptachlor, depending on the feasibility of implementation, are as follows:

• Process enclosure• local exhaust ventilation• General dilution ventilation• Personal protective equipment

Personal Protective Equipment [9]

The following is a list of recommended personal protective equipment when handling heptachlor:

• Respiratory protection: Where risk assessment shows air-purifying respirators are appropriate use a full-face particle respirator type N100 (uS) or type P3 (EN 143) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. use respirators and components tested and approved under appropriate government standards such as NIOSH (uS) or CEN(Eu).

• Hand protection: Handle with gloves. Gloves must be inspected prior to use. use proper glove removal technique (without touching glove’s outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands. The selected protective gloves have to satisfy the specifications of Eu Directive 89/686/EEC and the standard EN 374 derived from it.

• Eye protection: Face shield and safety glasses use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (uS) or EN 166(Eu).

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Hazard Alert• Skin and body protection: Complete suit protecting against chemicals,

the type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.

REGULATIONS [8,10]

United States

OSHA: The united States Occupational Safety and Health Administration permissible exposure limit (PEl) for heptachlor is 0.5 milligrams per cubic metre (mg/m3) of air as an 8-hour time-weighted average (TWA) concentration. The OSHA PEl also bears a “Skin” notation, which indicates that the cutaneous route of exposure (including mucous membranes and eyes) contributes to overall exposure [29 CFR 1910.1000, Table Z-1].

NIOSH: The National Institute for Occupational Safety and Health (NIOSH) has established a recommended exposure limit (REl) for heptachlor of 0.5 mg/m3 as a TWA for up to a 10-hour workday and a 40-hour workweek. NIOSH also assigns a “Skin” notation to heptachlor. NIOSH considers heptachlor a potential occupational carcinogen [NIOSH 1992].

ACGIH: The American Conference of Governmental Industrial Hygienists (ACGIH) has assigned heptachlor a threshold limit value (TlV) of 0.5 mg/m3 as a TWA for a normal 8-hour workday and a 40-hour workweek. The ACGIH also assigns a “Skin” notation to heptachlor. The ACGIH lists heptachlor as an animal carcinogen [ACGIH 1994, p. 22].

Australia

Safe Work Australia: Safe Work Australia have established a time weighted average (TWA) for heptachlor of 0.5 mg/m3 for a 40 hour work week.

REFERENCES

1. http://en.wikipedia.org/wiki/Heptachlor2. http://scorecard.goodguide.com/chemical-profiles/html/heptachlor.

html3. http://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=744&tid=1354. http://toxipedia.org/display/toxipedia/Heptachlor5. http://www.epa.gov/ttn/atw/hlthef/heptachl.html6. http://www.atsdr.cdc.gov/toxguides/toxguide-12.pdf7. http://www.chembase.com/pdf/readme.php?cbid=Heptachlor

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Hazard Alert8. http://www.osha.gov/SlTC/healthguidelines/heptachlor/recognition.

html9. http://www.sigmaaldrich.com/MSDS/MSDS/DisplayMSDSPage.do?cou

ntry=Au&language=en&productNumber=PS78&brand=SuPElCO&PageToGoTouRl=http%3A%2F%2Fwww.sigmaaldrich.com%2Fcatalog%2Fproduct%2Fsupelco%2Fps78%3Flang%3Den

10. http://www.safeworkaustralia.gov.au/sites/swa/search/results?k=heptachlor

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Copper and platinum nanoparticles added to the surface of a blue titania photo-catalyst significantly improve its ability to recycle atmospheric carbon dioxide into hydrocarbon fuels.

One-two-punch catalysts trapping CO2 for cleaner fuels2019-06-17Copper and platinum nanoparticles added to the surface of a blue titania photocatalyst significantly improve its ability to recycle atmospheric carbon dioxide into hydrocarbon fuels. The modified photocatalyst was developed and tested by researchers at the Daegu Gyeongbuk Institute of Science and Technology (DGIST), with colleagues in Korea, Japan, and the uS. It converted sunlight to fuel with an efficiency of 3.3% over 30-minute periods. This ‘photoconversion efficiency’ is an important milestone, the researchers report in their study published in the journal Energy and Environmental Science, as it means that large-scale use of this technology is becoming a more realistic prospect. Photocatalysts are semiconducting materials that can use the energy from sunlight to catalyse a chemical reaction. Scientists are investigating their use to trap harmful carbon dioxide from the atmosphere as one of many means to alleviate global warming. Some photocatalysts are being tested for their ability to recycle carbon dioxide into hydrocarbon fuels like methane, the main component found in natural gas. Methane combustion releases less carbon dioxide into the atmosphere compared to other fossil fuels, making it an attractive alternative. But scientists have been finding it difficult to manufacture photocatalysts that produce a large enough yield of hydrocarbon products for their use to be practical. Professor Su-Il In of DGIST’s Department of Energy Science and Engineering and his colleagues modified a blue titania photocatalyst by adding copper and platinum nanoparticles to its surface. Copper has good carbon dioxide adsorption property while platinum is very good at separating the much-needed charges generated by the blue titania from the sun’s energy. The team developed a unique set-up to accurately measure the catalyst’s photoconversion efficiency. The catalyst was placed in a chamber that received a quantifiable amount of artificial sunlight. Carbon dioxide gas and water vapour moved through the chamber, passing over the catalyst. An analyser measured the gaseous components coming out of the chamber as a result of the photocatalytic reaction. The blue titania catalyst converts the energy in sunlight into charges that are transferred to the carbon and hydrogen molecules in carbon dioxide and water to convert them into methane and ethane gases. The addition of copper and platinum nanoparticles on the catalyst’s surface was found to significantly improve the efficiency of this process. “The photocatalyst has a very high conversion efficiency and is relatively easy to manufacture, making it advantageous for commercialisation,” says Prof. In. “ The team plans to continue its efforts to further improve the catalyst’s photoconversion efficiency, to make it thick enough to absorb

Gossip

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In two system-atic reviews researchers identified points where better-designed studies would help character-ise infant exposures via breast milk and formula, as well as im-prove risk assessment.

Gossipall incident light, and to improve its mechanical integrity to enable easier handling.

EurekAlert, 7 June 2019

http://www.eurekalert.org

Baby Steps Forward: Recommendations for Better Understanding Environmental Chemicals in Breast Milk and Infant Formula2019-06-17The infant diet is typically limited to breast milk and/or infant formula for the first months of life. Yet relatively little is known about the environmental chemicals present in these foods and their potential short- and long-term effects on health. In two systematic reviews published in Environmental Health Perspectives, Geniece lehmann of the u.S. Environmental Protection Agency, Judy S. laKind of laKind Associates, llC, and colleagues identified points where better-designed studies would help characterise infant exposures via breast milk and formula, as well as improve risk assessment. More than 40,000 chemicals are currently in use in the united States. Pregnant women and infants may be exposed to chemicals in their environment via oral, inhalation, or dermal routes; there is also some risk of transplacental chemical exposures. Even for the small subset of environmental chemicals that are well studied, the effects of early life exposures are often unclear. “There are substantial gaps in our understanding of what chemicals, as well as what levels of them, would be concerning [for infants],” says Suzan Carmichael, a perinatal and nutritional epidemiologist at Stanford university, who was not involved with the reviews. Most of what we suspect, she says, is extrapolated from animal and adult data. Breast milk is a dynamic mixture of fats, sugars, and proteins, with compositional changes occurring both throughout a single feeding and over the course of lactation. The complex chemistry of breast milk makes it especially difficult for scientists to study its load of environmental chemicals, says Benedikt Warth, an analytical food chemist at the university of Vienna, who also was not involved in the reviews. It becomes even more challenging when researchers move from targeted studies of samples, which measure levels of specific compounds, to untargeted chemical screening, which tries to determine all chemicals present. During lactation, a woman’s body mobilises its adipose stores to produce fat-rich milk. That means that fat-soluble chemicals stored in the mother’s adipose tissue can be passed into her milk and on to her

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Gossipinfant. Persistent organic pollutants, such as polychlorinated biphenyls, dioxins, and polybrominated biphenyl ethers (PBDEs), are especially likely to be transmitted this way, lehmann says. But non–fat-soluble chemicals may still end up in breast milk. For example, per- and polyfluoroalkyl substances (PFAS) can accumulate in fat tissue by binding to serum proteins.4 From there, they too may be released during lactation. Although an estimated 81% of u.S. infants receive breast milk in the days immediately after birth, that number drops to about 52% by 6 months of age, and only half those infants are exclusively breastfed, according to the Centres for Disease Control and Prevention. Commercially available infant formula, mostly derived from cow’s milk or soy, fills in the gap, and there’s “almost a complete lack of information on environmental chemicals in infant formula,” lehmann says—potentially including chemicals in the water used to mix that formula. “The fact that we know so little about chemicals in infant formula is surprising to me,” lehmann says. “When comparing sources of infant nutrition, we need to know what chemicals are present in all of the candidate sources. Breast milk contains chemicals from the environment, but information about chemicals present in formula is also needed to support decisions about infant feeding.”

The team aimed to assess the potential threat posed by background levels of environmental chemicals in breast milk and formula. In the first of the two reviews, they screened 3,076 articles on chemicals in breast milk and 485 on chemicals in formula. Their goal was to determine what researchers currently know about the types and levels of these chemicals, and to assess the use of mathematical models to quantify potential health risk. The authors focused on research conducted in the united States since 2000 to estimate typical present-day exposures in u.S. women. A total of 44 articles on breast milk and 13 on formula met all inclusion criteria, including measurements of various environmental chemicals that enabled the authors to estimate average infant exposures. An in-depth risk analysis of three example studies—one on PBDEs in breast milk,6 one on dioxins in breast milk,7 and one on PFAS in formula—demonstrated that some studies to date may be used to assess potential health impact. However, a full risk analysis cannot be performed for most chemicals, given that safe exposure levels are unknown. In the second review, the authors screened studies on health outcomes related to environmental chemical exposures via breast milk and infant formula. Their goal in this review was to assess whether the scientific literature supports associations between chemical exposures via breast milk or formula and health outcomes later in life. For breast milk, they found 85 studies that met the inclusion criteria; for formula, they found none. The team grouped health outcomes into four

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Gossipbroad categories: growth and maturation, morbidity, biomarkers, and neurodevelopment. Although they did not identify consistent evidence for negative health effects from background levels of environmental chemicals, they noted that very few chemicals have been studied—fewer than 200 in all the studies reviewed. Much more research is needed to conclusively rule out the potential for negative health impacts. The team used a data storage and presentation tool called Tableau to make their results easier to navigate. The result was a series of interactive figures that are much more transparent than traditional figures. “Readers can easily identify the studies that go with each data point, which allows them to refer back to our original source material to verify our findings or conduct their own analyses,” lehmann says. The authors pointed to several areas where future studies can help fill in the many data gaps, with specific recommendations for study design. For example, investigators need to measure a wider variety of chemical types in breast milk and formula. Studies must be properly powered and include participants with both high and low chemical exposures. And study replicability is critical for conducting evidence synthesis. They also highlighted study areas that must be bolstered to inform risk assessment. They called for more studies on chemical mixtures and differentiation between prenatal and lactational exposures. In addition, future studies should measure chemical concentrations over the course of lactation as well as assess how breast milk concentrations of short-lived chemicals vary over time. Environmental health scientist Philippe Grandjean of the university of Southern Denmark calls the reviews “useful but incomplete” because the researchers excluded studies from outside the united States and those examining chemical exposures from natural sources, such as mycotoxins. He also feels the reviews should have highlighted that the duration of breastfeeding was incompletely analysed in the source articles. But Grandjean, who was not involved in the reviews, raises a broader concern about the body of literature on children’s exposures in general. “Both prenatal and the early postnatal periods are highly vulnerable times. We need to focus more on exposures during these windows,” he says. Even with the potential chemical exposures via breast milk, lehmann emphasises that this does not mean breastfeeding is not safe and beneficial. “There are many well-documented health benefits of breastfeeding, both for babies and their mothers,” she says. “From a public health perspective, we could continue to capitalise on these benefits by encouraging breastfeeding while reducing chemical exposures via breast milk by reducing mothers’ exposures to chemicals in the environment.” According to the evidence that’s currently available, she adds, the benefits of breast milk continue to outweigh risks for most infants. However, women should consult with their health care

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Gossipproviders if they have questions or concerns about what to feed their babies.

Environmental Health Perspectives, 4 June 2019

http://ehp03.niehs.nih.gov

Quantum physics experiment shows Heisenberg was right about uncertainty, in a certain sense2019-06-17The word uncertainty is used a lot in quantum mechanics. One school of thought is that this means there’s something out there in the world that we are uncertain about. But most physicists believe nature itself is uncertain. Intrinsic uncertainty was central to the way German physicist Werner Heisenberg, one of the originators of modern quantum mechanics, presented the theory. He put forward the uncertainty Principle that showed we can never know all the properties of a particle at the same time. For example, measuring the particle’s position would allow us to know its position. But this measurement would necessarily disturb its velocity, by an amount inversely proportional to the accuracy of the position measurement.

Was Heisenberg wrong?

Heisenberg used the uncertainty Principle to explain how measurement would destroy that classic feature of quantum mechanics, the two-slit interference pattern (more on this below). But back in the 1990s, some eminent quantum physicists claimed to have proved it is possible to determine which of the two slits a particle goes through, without significantly disturbing its velocity. Does that mean Heisenberg’s explanation must be wrong? In work just published in Science Advances, my experimental colleagues and I have shown that it would be unwise to jump to that conclusion. We show a velocity disturbance — of the size expected from the uncertainty Principle — always exists, in a certain sense. But before getting into the details we need to explain briefly about the two-slit experiment.

The two-slit experiment

In this type of experiment there is a barrier with two holes or slits. We also have a quantum particle with a position uncertainty large enough to cover both slits if it is fired at the barrier. Since we can’t know which slit the particle goes through, it acts as if it goes through both slits. The

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Gossipsignature of this is the so-called “interference pattern”: ripples in the distribution of where the particle is likely to be found at a screen in the far field beyond the slits, meaning a long way (often several metres) past the slits. But what if we put a measuring device near the barrier to find out which slit the particle goes through? Will we still see the interference pattern? We know the answer is no, and Heisenberg’s explanation was that if the position measurement is accurate enough to tell which slit the particle goes through, it will give a random disturbance to its velocity just large enough to affect where it ends up in the far field, and thus wash out the ripples of interference. What the eminent quantum physicists realised is that finding out which slit the particle goes through doesn’t require a position measurement as such. Any measurement that gives different results depending on which slit the particle goes through will do. And they came up with a device whose effect on the particle is not that of a random velocity kick as it goes through. Hence, they argued, it is not Heisenberg’s uncertainty Principle that explains the loss of interference, but some other mechanism.

As Heisenberg predicted

We don’t have to get into what they claimed was the mechanism for destroying interference, because our experiment has shown there is an effect on the velocity of the particle, of just the size Heisenberg predicted. We saw what others have missed because this velocity disturbance doesn’t happen as the particle goes through the measurement device. Rather it is delayed until the particle is well past the slits, on the way towards the far field. How is this possible? Well, because quantum particles are not really just particles. They are also waves. In fact, the theory behind our experiment was one in which both wave and particle nature are manifest — the wave guides the motion of the particle according to the interpretation introduced by theoretical physicist David Bohm, a generation after Heisenberg.

let’s experiment

In our latest experiment, scientists in China followed a technique suggested by me in 2007 to reconstruct the hypothesised motion of the quantum particles, from many different possible starting points across both slits, and for both results of the measurement. They compared the velocities over time when there was no measurement device present to those when there was, and so determined the change in the velocities as a result of the measurement. The experiment showed that the effect of the measurement on the velocity of the particles continued long after

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A new “virtual biopsy” device uses sound vibrations and pulses of near-infrared light instead of a scalpel to quickly determine a skin lesion’s depth and potential malignancy, a new study reports.

Gossipthe particles had cleared the measurement device itself, as far as 5 metres away from it. By that point, in the far field, the cumulative change in velocity was just large enough, on average, to wash out the ripples in the interference pattern. So, in the end, Heisenberg’s uncertainty Principle emerges triumphant. The take-home message? Don’t make far-reaching claims about what principle can or cannot explain a phenomenon until you have considered all theoretical formulations of the principle. Yes, that’s a bit of an abstract message, but it’s advice that could apply in fields far from physics.

The Conversation, 15 June 2019

http://www.theconversation

‘Virtual Biopsy’ Device Detects Skin Tumours In 15 Minutes2019-06-17A new “virtual biopsy” device uses sound vibrations and pulses of near-infrared light instead of a scalpel to quickly determine a skin lesion’s depth and potential malignancy, a new study reports. The ability to analyse a skin tumour non-invasively could make biopsies much less risky and distressing to patients, researchers say. Currently, physicians who perform surgical biopsies often don’t know the extent of a lesion–or the necessity of referring the patient to a specialist for extensive tissue removal or plastic surgery–until surgery has already begun. The first-of-its-kind experimental procedure, called vibrational optical coherence tomography (VOCT), creates a 3D map of the lesion’s width and depth under the skin with a tiny laser diode. It also uses soundwaves to test the lesion’s density and stiffness since cancer cells are stiffer than healthy cells. An inch-long speaker applies audible soundwaves against the skin to measure the skin’s vibrations and determine whether the lesion is malignant. “This procedure can be completed in 15 minutes with no discomfort to the patient, who feels no sensation from the light or the nearly inaudible sound. It’s a significant improvement over surgical biopsies, which are invasive, expensive, and time-consuming,” says Frederick Silver, a professor of pathology and laboratory medicine at Rutgers Robert Wood Johnson Medical School, and lead researcher of the paper in Skin Research & Technology. A prototype VOCT device accurately distinguished between healthy skin and different types of skin lesions and carcinomas, the study shows. The researchers tested the device over six months on four skin excisions and on eight volunteers without skin lesions. Further studies are needed to fine-tune the device’s ability to identify a lesion’s borders

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Researchers have developed nanobio-hybrid organisms capable of using airborne carbon di-oxide and nitrogen to produce a variety of plastics and fuels, a promising first step toward low-cost car-bon sequestration and eco-friendly manufac-turing for chemicals.

Gossipand areas of greatest density and stiffness, which would allow physicians to remove tumours with minimally invasive surgery. The researchers are currently waiting for FDA approval for large-scale testing. Additional researchers are from Rutgers, the Neigel Centre for Cosmetic and laser Surgery, and the Centre for Advanced Eye Care.

Futurity, 13 June 2019

http://www.futurity.org

Light-powered nano-organisms consume carbon dioxide, create eco-friendly plastics and fuels2019-06-17university of Colorado Boulder researchers have developed nanobio-hybrid organisms capable of using airborne carbon dioxide and nitrogen to produce a variety of plastics and fuels, a promising first step toward low-cost carbon sequestration and eco-friendly manufacturing for chemicals. By using light-activated quantum dots to fire particular enzymes within microbial cells, the researchers were able to create “living factories” that eat harmful CO2 and convert it into useful products such as biodegradable plastic, gasoline, ammonia and biodiesel. “The innovation is a testament to the power of biochemical processes,” said Prashant Nagpal, lead author of the research and an assistant professor in Cu Boulder’s Department of Chemical and Biological Engineering. “We’re looking at a technique that could improve CO2 capture to combat climate change and one day even potentially replace carbon-intensive manufacturing for plastics and fuels.” The project began in 2013, when Nagpal and his colleagues began exploring the broad potential of nanoscopic quantum dots, which are tiny semiconductors similar to those used in television sets. Quantum dots can be injected into cells passively and are designed to attach and self-assemble to desired enzymes and then activate these enzymes on command using specific wavelengths of light. Nagpal wanted to see if quantum dots could act as a spark plug to fire particular enzymes within microbial cells that have the means to convert airborne CO2 and nitrogen, but do not do so naturally due to a lack of photosynthesis. By diffusing the specially-tailored dots into the cells of common microbial species found in soil, Nagpal and his colleagues bridged the gap. Now, exposure to even small amounts of indirect sunlight would activate the microbes’ CO2 appetite, without a need for any source of energy or food to carry out the energy-intensive biochemical conversions. “Each cell is making millions of these chemicals and we showed they could exceed their natural yield by close to 200 percent,” Nagpal said. The microbes, which lie dormant

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A new method of discovering materials using data analytics and electron micros-copy has found a new class of extremely hard alloys. Such materials could potentially withstand severe impact from projectiles, providing better protection for soldiers in combat.

Gossipin water, release their resulting product to the surface, where it can be skimmed off and harvested for manufacturing. Different combinations of dots and light produce different products: Green wavelengths cause the bacteria to consume nitrogen and produce ammonia while redder wavelengths make the microbes feast on CO2 to produce plastic instead. The process also shows promising signs of being able to operate at scale. The study found that even when the microbial factories were activated consistently for hours at a time, they showed few signs of exhaustion or depletion, indicating that the cells can regenerate and thus limit the need for rotation. “We were very surprised that it worked as elegantly as it did,” Nagpal said. “We’re just getting started with the synthetic applications.” The ideal futuristic scenario, Nagpal said, would be to have single-family homes and businesses pipe their CO2 emissions directly to a nearby holding pond, where microbes would convert them to a bioplastic. The owners would be able to sell the resulting product for a small profit while essentially offsetting their own carbon footprint. “Even if the margins are low and it can’t compete with petrochemicals on a pure cost basis, there is still societal benefit to doing this,” Nagpal said. “If we could convert even a small fraction of local ditch ponds, it would have a sizeable impact on the carbon output of towns. It wouldn’t be asking much for people to implement. Many already make beer at home, for example, and this is no more complicated.” The focus now, he said, will shift to optimising the conversion process and bringing on new undergraduate students. Nagpal is looking to convert the project into an undergraduate lab experiment in the fall semester, funded by a Cu Boulder Engineering Excellence Fund grant. Nagpal credits his current students with sticking with the project over the course of many years. “It has been a long journey and their work has been invaluable,” he said. “I think these results show that it was worth it.” The new study was recently published in the Journal of the American Chemical Society and was co-authored by Yuchen Ding and John Bertram of Cu Boulder; Carrie Eckert of the National Renewable Energy laboratory; and Rajesh Bommareddy, Rajan Patel, Alex Conradie and Samantha Bryan of the university of Nottingham (united Kingdom).

Science Daily, 11 June 2019

http://www.sciencedaily.com

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Jul. 12, 2019

GossipMaterials informatics reveals new class of super-hard alloys2019-06-17A new method of discovering materials using data analytics and electron microscopy has found a new class of extremely hard alloys. Such materials could potentially withstand severe impact from projectiles, thereby providing better protection of soldiers in combat. Researchers from lehigh university describe the method and findings in an article, “Materials Informatics For the Screening of Multi-Principal Elements and High-Entropy Alloys,” that appears in Nature Communications. “We used materials informatics -- the application of the methods of data science to materials problems -- to predict a class of materials that have superior mechanical properties,” said primary author Jeffrey M. Rickman, professor of materials science and engineering and physics and Class of ‘61 Professor at lehigh university. Researchers also used experimental tools, such as electron microscopy, to gain insight into the physical mechanisms that led to the observed behaviour in the class of materials known as high-entropy alloys (HEAs). High-entropy alloys contain many different elements that, when combined, may result in systems having beneficial and sometimes unexpected thermal and mechanical properties. For that reason, they are currently the subject of intense research. “We thought that the techniques that we have developed would be useful in identifying promising HEAs,” Rickman said. “However, we found alloys that had hardness values that exceeded our initial expectations. Their hardness values are about a factor of 2 better than other, more typical high-entropy alloys and other relatively hard binary alloys.”

Rise of High-Entropy Alloys and Data Analysis

The field of high-entropy, or multi-principal element, alloys has recently seen exponential growth. These systems represent a paradigm shift in alloy development, as some exhibit new structures and superior mechanical properties, as well as enhanced oxidation resistance and magnetic properties, relative to conventional alloys. However, identifying promising HEAs has presented a daunting challenge, given the vast palette of possible elements and combinations that could exist. Researchers have sought a way to identify the element combinations and compositions that lead to high-strength, high-hardness alloys and other desirable qualities, which are a relatively small subset of the large number of potential HSAs that could be created. In recent years, materials informatics, the application of data science to problems in materials science and engineering, has emerged as a powerful tool

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Jul. 12, 2019

Chemists have de-veloped an efficient process for converting carbon dioxide into carbon monoxide, a key ingredient of synthetic fuels and materials.

Gossipfor materials discovery and design. The relatively new field is already having a significant impact on the interpretation of data for a variety of materials systems, including those used in thermoelectrics, ferroelectrics, battery anodes and cathodes, hydrogen storage materials, and polymer dielectrics. “Creation of large data sets in materials science, in particular, is transforming the way research is done in the field by providing opportunities to identify complex relationships and to extract information that will enable new discoveries and catalyse materials design,” Rickman said. The tools of data science, including multivariate statistics, machine learning, dimensional reduction and data visualisation, have already led to the identification of structure-property-processing relationships, screening of promising alloys and correlation of microstructure with processing parameters. lehigh university’s research contributes to the field of materials informatics by demonstrating that this suite of tools is extremely useful for identifying promising materials from among myriad possibilities. “These tools can be used in a variety of contexts to narrow large experimental parameter spaces to accelerate the search for new materials,” Rickman said.

New Method Combines Complementary Tools

lehigh university researchers combined two complementary tools to employ a supervised learning strategy for the efficient screening of high-entropy alloys and to identify promising HEAs: (1) a canonical-correlation analysis and (2) a genetic algorithm with a canonical-correlation analysis-inspired fitness function. They implemented this procedure using a database for which mechanical property information exists and highlighting new alloys with high hardnesses. The methodology was validated by comparing predicted hardnesses with alloys fabricated in a laboratory using arc-melting, identifying alloys with very high measured hardnesses. “The methods employed here involved a novel combination of existing methods adapted to the high-entropy alloy problem,” Rickman said. “In addition, these methods may be generalised to discover, for example, alloys having other desirable properties. We believe that our approach, which relies on data science and experimental characterization, has the potential to change the way researchers discover such systems going forward.” The research was funded by the Office of Naval Research with support from lehigh university’s Nano/Human Interface Initiative.

Science Daily, 13 June 2019

http://www.sciencedaily.com

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Jul. 12, 2019

GossipCarbon-neutral fuels move a step closer2019-06-17The carbon dioxide (CO2) produced when fossil fuels are burned is normally released into the atmosphere. Researchers working on synthetic fuels -- also known as carbon-neutral fuels -- are exploring ways to capture and recycle that CO2. At EPFl, this research is spearheaded by a team led by Professor Xile Hu at the laboratory of Inorganic Synthesis and Catalysis (lSCI). The chemists have recently made a landmark discovery, successfully developing a high-efficiency catalyst that converts dissolved CO2 into carbon monoxide (CO) -- an essential ingredient of all synthetic fuels, as well as plastics and other materials. The researchers published their findings in Science on 14 June.

Replacing gold with iron

The new process is just as efficient as previous technologies, but with one major benefit. “To date, most catalysts have used atoms of precious metals such as gold,” explains Professor Hu. “But we’ve used iron atoms instead. At extremely low currents, our process achieves conversion rates of around 90%, meaning it performs on a par with precious-metal catalysts.” “Our catalyst converts such a high percentage of CO2 into CO because we successfully stabilised iron atoms to achieve efficient CO2 activation,” adds Jun Gu, a PhD student and lead author of the paper. To help them understand why their catalyst was so highly active, the researchers called on a team led by Professor Hao Ming Chen at National Taiwan university, who conducted a key measurement of the catalyst under operating conditions using synchrotron X-rays.

Closing the carbon cycle

Although the team’s work is still very much experimental, the research paves the way for new applications. At present, most of the carbon monoxide needed to make synthetic materials is obtained from petroleum. Recycling the carbon dioxide produced by burning fossil fuels would help preserve precious resources, as well as limit the amount of CO2 -- a major greenhouse gas -- released into the atmosphere. The process could also be combined with storage batteries and hydrogen-production technologies to convert surplus renewable power into products that could fill the gap when demand outstrips supply.

Science Daily, 13 June 2019

http://www.sciencedaily.com

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Jul. 12, 2019

A new study reveals a “hidden” phase of strontium titanate.

GossipRevealing ‘hidden’ phases of matter through the power of light2019-06-17Most people think of water as existing in only one of three phases: Solid ice, liquid water, or gas vapor. But matter can exist in many different phases—ice, for example, has more than ten known phases, or ways that its atoms can be spatially arranged. The widespread use of piezoelectric materials, such as microphones and ultrasound, is possible thanks to a fundamental understanding of how an external force, like pressure, temperature, or electricity, can lead to phase transitions that imbue materials with new properties. A new study finds that a metal oxide has a “hidden” phase, one that gives the material new, ferroelectric properties, the ability to separate positive and negative charges, when it is activated by extremely fast pulses of light. The research was led by MIT researchers and the findings were published in Science. Their work opens the door to creating materials where one can turn on and off properties in a trillionth of a second with the flick of a switch, now with much better control. In addition to changing electric potential, this approach could be used to change other aspects of existing materials—turning an insulator into a metal or flipping its magnetic polarity, for example. “It’s opening a new horizon for rapid functional material reconfiguration,” says Rappe. The group studied strontium titanate, a paraelectric material used in optical instruments, capacitors, and resistors. Strontium titanate has a symmetric and nonpolar crystal structure that can be “pushed” into a phase with a polar, tetragonal structure with a pair of oppositely charged ions along its long axis. Nelson and Rappe’s previous collaboration provided the theoretical basis for this new study, which relied on Nelson’s experience using light to induce phase transitions in solid materials along with Rappe’s knowledge in developing atomic-level computer models. “[Nelson is] the experimentalist, and we’re the theorists,” says Rappe. “He can report what he thinks is happening based on spectra, but the interpretation is speculative until we provide a strong physical understanding of what happened.” With recent improvements in technology and additional knowledge gained from working with terahertz frequencies, the two chemists set out to see if their theory, now more than one decade old, held true. Rappe’s challenge was to complement Nelson’s experiments with an accurate computer-generated version of strontium titanate, with every single atom tracked and represented, that responds to light in the same manner as the material being tested in the lab. They found that when strontium titanate is excited with light, the ions are pulled in different directions, with positively charged ions moving in one direction

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Jul. 12, 2019

Researchers de-signed two-step process to break down rice straws into sugars for fuel.

Gossipand negatively charged ions in the other. Then, instead of the ions immediately falling back into place, the way a pendulum would after it’s been pushed, vibrational movements induced in the other atoms prevent the ions from swinging back immediately. It’s as if the pendulum, at the moment that it reaches the maximum height of its oscillation, is diverted slightly off course where a small notch holds it in place away from its initial position. Thanks to their strong history of collaboration, Nelson and Rappe were able to go back and forth from the theoretical simulations to the experiments, and vice versa, until they found experimental evidence that showed that their theory held true. “It’s been a really awesome collaboration,” says Nelson. “And it illustrates how ideas can simmer and then return in full force after more than 10 years.” The two chemists will collaborate with engineers on future applications-driven research, such as creating new materials that have hidden phases, changing light-pulse protocols to create longer-lasting phases, and seeing how this approach works for nanomaterials. For now, both researchers are excited about their results and where this fundamental breakthrough could lead to in the future. “It’s the dream of every scientist: To hatch an idea together with a friend, to map out the consequence of that idea, then to have a chance to translate it into something in the lab, it’s extremely gratifying. It makes us think we’re on the right track towards the future,” says Rappe.

Phys.org, 14 June 2019

http://phys.org

Researchers take two steps toward green fuel2019-06-17An international collaboration led by scientists at Tokyo university of Agriculture and Technology (TuAT), Japan, has developed a two-step method to more efficiently break down carbohydrates into their single sugar components, a critical process in producing green fuel. The researchers published their results on in the American Chemical Society journal, Industrial & Engineering Chemical Research. The breakdown process is called saccharification. The single sugar components produced, called monosaccharides, can be fermented into bioethanol or biobutanol, alcohols that can be used as fuel. “For a long time, considerable attention has been focused on the utilisation of homogenous acids and enzymes for saccharification,” said Eika W. Qian, paper author and professor in the Graduate School of Bio-Applications and Systems Engineering at the Tokyo university of Agriculture and Technology in Japan. “Enzymatic saccharification is seen to be a reasonable prospect

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Researchers have mapped how gold nanoparticles melt

Gossipsince it offers the potential for higher yields, lower energy costs, and it’s more environmentally friendly.” The use of enzymes to break down the carbohydrates could actually be hindered, especially in the practical biomass such as rice straw. A by-product of rice harvest, rice straw consists of three complicated carbohydrates: starch, hemicellulose and cellulose. Enzymes cannot approach hemicellulose or cellulose, due to their cell wall structure and surface area, among other characteristics. They must be pre-treated to become receptive to the enzymatic activity, which can be costly. One answer to the cost and inefficiency of enzymes is the use of solid acid catalysts, which are acids that cause chemical reactions without dissolving and becoming a permanent part of the reaction. They’re particularly appealing because they can be recovered after saccharification and reused. Still, it’s not as easy as swapping the enzymes for the acids, according to Qian, as the carbohydrates are non-uniform. Hemicellulose and starch degrade at 180 degrees Celsius and below, and if the resulting components are heated further, the sugars produced discompose and are converted to other by-products. On the other hand, degradation of cellulose only happens at temperatures of 200 degrees Celsius and above. That’s why, in order to maximise the resulting yield of sugar from rice straw, the researchers developed a two-step process—one step for the hemicellulose and another for the cellulose. The first step requires a gentle solid acid at low temperatures (150 degrees Celsius and below), while the second step consists of harsher conditions, with a stronger solid acid and higher temperatures (210 degrees Celsius and above). Overall, the two-step process not only proved effective, it produced about 30 percent more sugars than traditional one-step processes. “We are now looking for a partner to evaluate the feasibility of our two-step saccharification process in rice straw and other various materials such as wheat straw and corn stoke etc. in a pilot unit,” Qian said. “Our ultimate goal is to commercialize our process to manufacture monosaccharides from this type of material in the future.”

Phys.org, 14 June 2019

http://phys.org

Research reveals liquid gold on the nanoscale2019-06-17The research published in Nature Communications set out to answer a simple question - how do nanoparticles melt? Although this question has been a focus of researchers for the past century, it still is an open problem - initial theoretical models describing melting date from around

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The new anode could help create a safer high energy lithium metal battery

Gossip100 years, and even the most relevant models being some 50 years old. Professor Richard Palmer, who led the team based at the university’s College of Engineering said of the research: “Although melting behaviour was known to change on the nanoscale, the way in which nanoparticles melt was an open question. Given that the theoretical models are now rather old, there was a clear case for us to carry out our new imaging experiments to see if we could test and improve these theoretical models.” The research team used gold in their experiments as it acts as a model system for noble and other metals. The team arrived at their results by imaging gold nanoparticles, with diameters ranging from 2 to 5 nanometres, via aberration corrected scanning transmission electron microscope. Their observations were later supported by large-scale quantum mechanical simulations. Professor Palmer said: “We were able to prove the dependence of the melting point of the nanoparticles on their size and for the first time see directly the formation of a liquid shell around a solid core in the nanoparticles over a wide region of elevated temperatures, in fact for hundreds of degrees. “This helps us to describe accurately how nanoparticles melt and to predict their behaviour at elevated temperatures. This is a science breakthrough in a field we can all relate to - melting - and will also help those producing nanotech devices for a range of practical and everyday uses, including medicine, catalysis and electronics.”

EurekAlert, 13 June 2019

http://www.eurekalert.org

Semi-liquid metal anode for next-generation batteries2019-06-17Researchers from Carnegie Mellon university’s Mellon College of Science and College of Engineering have developed a semiliquid lithium metal-based anode that represents a new paradigm in battery design. lithium batteries made using this new electrode type could have a higher capacity and be much safer than typical lithium metal-based batteries that use lithium foil as anode. The interdisciplinary research team published their findings in the current issue of Joule. lithium-based batteries are one of the most common types of rechargeable battery used in modern electronics due to their ability to store high amounts of energy. Traditionally, these batteries are made of combustible liquid electrolytes and two electrodes, an anode and a cathode, which are separated by a membrane. After a battery has been charged and discharged repeatedly, strands of lithium called dendrites can grow on the surface of the

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Gossipelectrode. The dendrites can pierce through the membrane that separates the two electrodes. This allows contact between the anode and cathode, which can cause the battery to short circuit and, in the worst case, catch fire. “Incorporating a metallic lithium anode into lithium-ion batteries has the theoretical potential to create a battery with much more capacity than a battery with a graphite anode,” said Krzysztof Matyjaszewski, J.C. Warner university Professor of Natural Sciences in Carnegie Mellon’s Department of Chemistry. “But, the most important thing we need to do is make sure that the battery we create is safe.” One proposed solution to the volatile liquid electrolytes used in current batteries is to replace them with solid ceramic electrolytes. These electrolytes are highly conductive, non-combustible and strong enough to resist dendrites. However, researchers have found that the contact between the ceramic electrolyte and a solid lithium anode is insufficient for storing and supplying the amount of power needed for most electronics. Sipei li, a doctoral student in Carnegie Mellon’s Department of Chemistry, and Han Wang, a doctoral student in Carnegie Mellon’s Department of Materials Science and Engineering, were able to surmount this shortcoming by creating a new class of material that can be used as a semiliquid metal anode. Working with the Mellon College of Science’s Matyjaszewski, a leader in polymer chemistry and materials science, and Jay Whitacre, Trustee Professor in Energy in the College of Engineering and director of the Wilton E. Scott Institute for Energy Innovation at Carnegie Mellon, who is renowned for his work in developing new technologies for energy storage and generation, li and Wang created a dual-conductive polymer/carbon composite matrix that has lithium microparticles evenly distributed throughout. The matrix remains flowable at room temperatures, which allows it to create a sufficient level of contact with the solid electrolyte. By combining the semiliquid metal anode with a garnet-based solid ceramic electrolyte, they were able to cycle the cell at 10 times higher current density than cells with a solid electrolyte and a traditional lithium foil anode. This cell also had a much longer cycle-life than traditional cells. “This new processing route leads to a lithium metal-based battery anode that is flowable and has very appealing safety and performance compared to ordinary lithium metal. Implementing new material like this could lead to step change in lithium-based rechargeable batteries, and we are working hard to see how this works in a range of battery architectures,” said Whitacre. The researchers believe that their method could have far reaching impacts. For example, it could be used to create high capacity batteries for electric vehicles and specialised batteries for use in wearable devices that require flexible batteries. They also believe that their methods could be extended beyond lithium to other rechargeable battery systems, including sodium

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Scientists have dis-covered that healthy bacteria cells and cells inhibited by antibiot-ics or UV light show completely different electric reactions.

Gossipmetal batteries and potassium metal batteries and might be able to be used in grid-scale energy storage.

Science Daily, 12 June 2019

http://www.sciencedaily.com

Bacteria such as E. coli detected in minutes by new tech2019-06-17A discovery by researchers at the School of life Sciences at the university of Warwick offers a new technology for detecting bacteria in minutes by ‘zapping’ the bacteria with electricity. Testing clinical samples or commercial products for bacterial contamination typically takes days. During this time, they can cause significant damage; many infections can become life threatening very quickly if not identified and treated with appropriate antibiotics. For example, 8% of people with severe blood infection sepsis will die for every hour of delay in proper treatment. More routine problems like urinary tract infections are difficult to diagnose and some people cannot get a clear answer about their symptoms due to difficulties with detecting low-level infections. Studies have found 20-30% of urinary tract infections are missed by dipstick tests used for detecting bacteria in the urine. Scientists at the university of Warwick have discovered that healthy bacteria cells and cells inhibited by antibiotics or uV light showed completely different electric reactions. They made this discovery by combining biological experiments, engineering and mathematical modelling. Published in Proceedings of the National Academy of Sciences of the uSA (PNAS), these findings could lead to the development of medical devices which can rapidly detect live bacterial cells, evaluate the effects of antibiotics on growing bacteria colonies, or which could identify different types of bacteria and reveal antibiotic-resistant bacteria. The researchers have an ambitious plan to deliver the technology to market to maximise social good and have founded a start-up company Cytecom to commercialise the idea. The company has been awarded a grant from Innovate uK, the national innovation funding agency. This governmental support accelerates the process and the devices will be available to researchers and businesses in the very near future. Dr Munehiro Asally, Assistant Professor at the university of Warwick comments: “It is such an exciting time to work on bio-electricity of bacterial cells. This work demonstrates that bacterial electricity can lead to societally important technology, while at the same time gaining fundamental insights into our basic understanding of cells. The tool we developed can offer more opportunities by allowing experiments which

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Researchers say replacing at least 35 percent of Houston’s gasoline cars and diesel trucks with electric vehicles by 2040 will reduce pol-lution and improve air quality by 50 percent.

Gossipwere not possible to perform before.” Dr James Stratford, from the School of life Sciences and Warwick spinout company Cytecom comments: “The system we have created can produce results which are similar to the plate counts used in medical and industrial testing but about 20x faster. This could save many people’s lives and also benefit the economy by detecting contamination in manufacturing processes.” Dr Yoshikatsu Hayashi, from the university of Reading, comments: “using the widely used mathematical model in Neuroscience, we revealed a common mechanism of excitable cells, neuron and bacteria cells, and the extended neuronal model could explain two distinct electric reactions of healthy and unhealthy bacteria cells. Surprisingly, a single parameter representing the degree of non-equilibrium across the membrane was sufficient to explain the distinct responses of the cells. This is an important step towards understanding the origin of electrical signalling.”

Science Daily, 12 June 2019

http://www.sciencedaily.com

Electric vehicles would be a breath of fresh air for Houston2019-06-17Cornell university researchers are expressing hope for the future of Houston’s breathable air, despite the city’s poor rankings in the American lung Association’s 2019 “State of the Air” report. The report, released in April, ranked Houston ninth nationally for worst ozone pollution and 17th for particle pollution. Researchers say replacing at least 35 percent of Houston’s gasoline cars and diesel trucks with electric vehicles by 2040 will reduce pollution and improve air quality by 50 percent. “The built environment plays a significant role in affecting our daily life and health,” said H. Oliver Gao, professor of civil and environmental engineering and senior author of “Potential Impacts of Electric Vehicles on Air Quality and Health Endpoints in the Greater Houston Area in 2040,” published in Atmospheric Environment. “While transportation provides us with mobility, it impacts our environment and our public health,” said Gao, who directs Cornell’s Centre for Transportation, Environment and Community Health and is a fellow at Cornell’s Atkinson Centre for a Sustainable Future. “We are enjoying this mobility at a very high cost.” Shuai Pan, postdoctoral associate in civil and environmental engineering, along with Gao and a team of chemists and engineers, modelled four scenarios using various levels of electric car adoption to see how Houston’s air quality and public health likely would respond two decades from now. “The population in

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Researchers in Japan have presented an organic catalyst for carbon dioxide (CO2) reduction that is inexpensive, readily available and recyclable.

Gossip2040 Houston will see a huge increase, but we can apply new technology to reduce emissions, improve air quality and think about health,” said Pan, who earned his Ph.D. in atmospheric science from the university of Houston in 2017. In their exhaust, gasoline and diesel vehicles emit nitrogen oxides -- volatile organic compounds that react in the presence of sunlight to form ozone and increase detrimental fine particulates, elements known to harm human health. If left unchecked, current ozone and particulate-matter levels would result in 122 more premature deaths annually throughout greater Houston by 2040. With moderate or aggressive electrification for cars and trucks, the numbers reflect air-quality improvement, with prevented premature deaths at 114 and 188, respectively. In the case of complete turnover to electric vehicles, the number of prevented premature deaths per year around Houston shoots to 246. “Mayors or policymakers -- who care about the environment, the economy and public health -- must advocate for electrification,” Gao said. “The knowledge is there, but we need mayors and city planners to be creative and innovative to design policies that would help the electrification of the transportation sector.”

Science Daily, 11 June 2019

http://www.sciencedaily.com

A metal-free, sustainable approach to carbon dioxide reduction2019-06-17Researchers in Japan have presented an organic catalyst for carbon dioxide (CO2) reduction that is inexpensive, readily available and recyclable. As the level of catalytic activity can be tuned by the solvent conditions, their findings could open up many new directions for converting CO2 to industrially useful organic compounds. Sustainability is a key goal in the development of next-generation catalysts for CO2 reduction. One promising approach is a reaction called the hydrosilylation of CO2. However, most catalysts developed to date for this purpose have the disadvantage of containing metals that are expensive, not widely available and potentially detrimental to the environment. Now, scientists at Tokyo Institute of Technology (Tokyo Tech) and the Renewable Energy Research Centre at Japan’s National Institute of Advanced Industrial Science and Technology (AIST) have demonstrated the possibility of using a fully recyclable, metal-free catalyst. By comparing how well different organic catalysts could achieve hydrosilylation of CO2, the team identified one that surpassed all others in terms of selectivity and yield. This catalyst,

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Scientists have now demonstrated that a newly developed, more ecological syn-thetic route is suitable for the production of a wide variety of cepha-losporin antibiotics.

Gossipcalled tetrabutylammonium (TBA) formate, achieved 99 percent selectivity and produced the desired formate product with a 98 percent yield. The reaction occurred rapidly (within 24 hours) and under mild conditions, at a temperature of 60°C. Remarkably, the catalyst has a turnover number of up to 1800, which is more than an order of magnitude higher than previous results. In 2015, team leader Ken Motokura of Tokyo Tech’s Department of Chemical Science and Engineering and his colleagues found that formate salts show promising catalytic activity. It was this hint that provided the basis for the current study. Motokura explains: “Although we did expect formate salts to exhibit good catalytic activity, TBA formate showed much higher selectivity, stability and activity that went beyond our expectations.” In the current study, the researchers found that the catalyst can be made reusable by using toluene as a solvent. They showed that lewis basic solvents such as N-methylpyrrolidone (NMP) and dimethyl sulfoxide (DMSO) can accelerate the reaction, meaning that the catalytic system is tunable. Overall the findings—published in the online edition of the journal ACS Sustainable Chemistry & Engineering—offer a new, environmentally friendly path to reducing CO2 at the same time as yielding industrially important formate products. Silyl formate can be easily converted to formic acid, which can serve as an important hydrogen carrier, for example, in fuel cells. The high reactivity of silyl formate enables its conversion into intermediates for the preparation of organic compounds such as carboxylic acids, amides and alcohols. “This efficient transformation technique of CO2 to silyl formate will expand the possibilities for CO2 utilization as a chemical feedstock,” Motokura says.

Phys.org, 14 June 2019

http://phys.org

Researchers report efficient platform technology for producing cephalosporin antibiotics2019-06-17Antibiotics save countless human lives—modern medicine without them is unimaginable. The largest proportion by volume of industrially produced antibiotics today are cephalosporins, structural variants of the first antibiotic, penicillin. unfortunately, their production generates a considerable amount of waste products, some of which are questionable. In the European Journal of Organic Chemistry, scientists have now demonstrated that a newly developed, more ecological synthetic route is suitable for the production of a wide variety of cephalosporin antibiotics. Penicillin is among the ß-lactam antibiotics, a class of substances whose

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Gossipcommon component is a lactam, a four-membered ring consisting of one nitrogen atom and three carbon atoms, one of which is attached to an oxygen atom through a double bond. Cephalosporins, the second most significant subclass of the ß-lactam antibiotics, contain a bicyclic system made of the ß-lactam ring and a six-membered ring made of sulfur, nitrogen, and carbon atoms. The various therapeutically useful drugs in this class differ in their side chains, which can be attached at various places on the basic framework. The production of cephalosporin antibiotics is a semi-synthetic process. A fermentation first yields cephalosporin C, which is then enzymatically split to form 7-aminocephalosporanic acid (7-ACA). Different drugs are then produced from 7-ACA through chemical syntheses. Production of third-generation cephalosporin antibiotics involves attachment of an amino group (a nitrogen-containing group) of the lactam ring to a building block based on (Z)-(2-aminothiazol-4-yl)methoxyiminoacetic acid. Both the production of this reactant and the binding reaction are ecologically unfavourable because they result in large amounts of dubious waste products. These are formed because a variety of reagents are needed for activation, for protection of groups that are not supposed to react, and for the coupling itself, depending on which drug is being produced. A team headed by Harald Gröger (Bielefeld university, Germany) recently cooperated with the Provadis School of International Management and Technology and the generic drugs manufacturer Sandoz GmbH (Kundl, Austria) to develop an interesting alternative for this type of amidation reaction, and used it to make cefotaxime. The key to their success was the use of tosyl chloride, an established, inexpensive coupling reagent, in combination with methanol as an unproblematic solvent. The only side product is toluenesulfonyl acid, which is more attractive from the toxicological point of view since it requires neither protective groups nor activators that could form waste products. “This is a very favourable process with regard to atom economics,” says Gröger. Atom economics considers the percentage of atoms in the starting materials that are actually transferred to the products in a chemical reaction. Scientists at Bielefeld university and Sandoz GmbH, a leading producer of antibiotics, have now been able to demonstrate that their amidation method is generally suitable for the production of third-generation cephalosporin antibiotics. In a research project funded by the Deutsche Bundesstiftung umwelt (DBu, German Foundation for the Environment), they successfully synthesised three further cephalosporin antibiotics: cefpodoxime, cefpodoxime proxetil, and a precursor of ceftazidime. Despite non-optimised reaction conditions, their yields of 82 to 95 percent are very high. “It is particularly noteworthy that many different functional groups at diverse positions on the 7-ACA-based starting molecules are tolerated,”

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Sodium-containing compounds, such as those found in common household ingredients like detergent, baking soda, and table salt, are surprisingly effec-tive ingredients for cooking up carbon nanotubes, new MIT study finds.

Gossipsays Gröger. “Our ecologically and economically advantageous synthetic route offers the prospect of broad application in the industrial production of cephalosporin antibiotics.”

Phys.org, 14 June 2019

http://phys.org

Household Ingredients Rich in Sodium Help Grow Carbon Nanotubes2019-06-17Baking soda, table salt, and detergent are surprisingly effective ingredients for cooking up carbon nanotubes, researchers at MIT have found. In a study published this week in the journal Angewandte Chemie, the team reports that sodium-containing compounds found in common household ingredients are able to catalyse the growth of carbon nanotubes, or CNTs, at much lower temperatures than traditional catalysts require. The researchers say that sodium may make it possible for carbon nanotubes to be grown on a host of lower-temperature materials, such as polymers, which normally melt under the high temperatures needed for traditional CNT growth. “In aerospace composites, there are a lot of polymers that hold carbon fibres together, and now we may be able to directly grow CNTs on polymer materials, to make stronger, tougher, stiffer composites,” says Richard li, the study’s lead author and a graduate student in MIT’s Department of Aeronautics and Astronautics. “using sodium as a catalyst really unlocks the kinds of surfaces you can grow nanotubes on.”

Peeling onions

under a microscope, carbon nanotubes resemble hollow cylinders of chicken wire. Each tube is made from a rolled up lattice of hexagonally arranged carbon atoms. The bond between carbon atoms is extraordinarily strong, and when patterned into a lattice, such as graphene, or as a tube, such as a CNT, such structures can have exceptional stiffness and strength, as well as unique electrical and chemical properties. As such, researchers have explored coating various surfaces with CNTs to produce stronger, stiffer, tougher materials. Researchers typically grow CNTs on various materials through a process called chemical vapor deposition. A material of interest, such as carbon fibres, is coated in a catalyst — usually an iron-based compound — and placed in a furnace, through which carbon dioxide and other carbon-containing gases flow. At temperatures of up to 800 degrees Celsius, the iron starts to draw carbon

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Gossipatoms out of the gas, which glom onto the iron atoms and to each other, eventually forming vertical tubes of carbon atoms around individual carbon fibres. Researchers then use various techniques to dissolve the catalyst, leaving behind pure carbon nanotubes. li and his colleagues were experimenting with ways to grow CNTs on various surfaces by coating them with different solutions of iron-containing compounds, when the team noticed the resulting carbon nanotubes looked different from what they expected. “The tubes looked a little funny, and Rich and the team carefully peeled the onion back, as it were, and it turns out a small quantity of sodium, which we suspected was inactive, was actually causing all the growth,” Wardle says.

Tuning sodium’s knobs

For the most part, iron has been the traditional catalyst for growing CNTs. Wardle says this is the first time that researchers have seen sodium have a similar effect. “Sodium and other alkali metals have not been explored for CNT catalysis,” Wardle says. “This work has led us to a different part of the periodic table.” To make sure their initial observation wasn’t just a fluke, the team tested a range of sodium-containing compounds. They initially experimented with commercial-grade sodium, in the form of baking soda, table salt, and detergent pellets, which they obtained from the campus convenience store. Eventually, however, they upgraded to purified versions of those compounds, which they dissolved in water. They then immersed a carbon fibre in each compound’s solution, coating the entire surface in sodium. Finally, they placed the material in a furnace and carried out the typical steps involved in the chemical vapor deposition process to grow CNTs. In general, they found that, while iron catalysts form carbon nanotubes at around 800 degrees Celsius, the sodium catalysts were able to form short, dense forests of CNTs at much lower temperatures, of around 480 C. What’s more, after surfaces spent about 15 to 30 minutes in the furnace, the sodium simply vaporised away, leaving behind hollow carbon nanotubes. “A large part of CNT research is not on growing them, but on cleaning them —getting the different metals used to grow them out of the product,” Wardle says. “The neat thing with sodium is, we can just heat it and get rid of it, and get pure CNT as product, which you can’t do with traditional catalysts.” li says future work may focus on improving the quality of CNTs that are grown using sodium catalysts. The researchers observed that while sodium was able to generate forests of carbon nanotubes, the walls of the tubes were not perfectly aligned in perfectly hexagonal patterns — crystal-like configurations that give CNTs their characteristic strength. li plans to “tune various knobs” in

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Magnet generates an unprecedented 45.5-tesla field.

Gossipthe CVD process, changing the timing, temperature, and environmental conditions, to improve the quality of sodium-grown CNTs. “There are so many variables you can still play with, and sodium can still compete pretty well with traditional catalysts,” li says. “We anticipate with sodium; it is possible to get high quality tubes in the future. And we have pretty high confidence that, even if you were to use regular Arm and Hammer baking soda, it should work.” For Shigeo Maruyama, professor of mechanical engineering at the university of Tokyo, the ability to cook up CNTs from such a commonplace ingredient as sodium should reveal new insights into the way the exceptionally strong materials grow. “It is a surprise that we can grow carbon nanotubes from table salt!” says Maruyama, who was not involved in the research. “Even though chemical vapor deposition (CVD) growth of carbon nanotubes has been studied for more than 20 years, nobody has tried to use alkali group metal as catalyst. This will be a great hint for the fully new understanding of growth mechanism of carbon nanotubes.” This research was supported, in part, by Airbus, Boeing, Embraer, lockheed Martin, Saab AB, ANSYS, Saertex, and TohoTenax through MIT’s Nano-Engineered Composite aerospace STructures (NECST) Consortium.

Sci Tech Daily, 2 June 2019

https://scitechdaily.com/

Superconducting magnet breaks strength world record2019-06-17Scientists have created the world’s most powerful superconducting magnet, capable of generating a record magnetic field intensity of 45.5 tesla. Only pulsed magnets, which sustain fields for a fraction of a second at a time, have achieved higher intensities. Materials scientist David larbalestier and his collaborators at the uS National High Magnetic Field laboratory (NHMFl) in Tallahassee, Florida, ran intense electric currents through coils made of a cuprate superconductor to generate magnetic fields with low energy consumption. The resulting field strength exceeded that of energy-hungry resistive magnets — which don’t use superconductors — used by state-of-the-art magnet labs. It also surpassed conventional superconductor magnets, and ‘hybrid’ superconducting–resistive magnets (see ‘Record-breaking magnets’). The results were published 12 June in Nature1. Previous cuprate-based magnets have been too fragile for use in technological applications, but the novel design should be able to sustain fields of up to 60 tesla, larbalestier says. Thousands of researchers take their samples to magnet facilities such as

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Marine snow is the phenomena of flakes of falling organic material and biologi-cal debris cascading down a water column like snowflakes. But an oil spill like Deepwa-ter Horizon will add oil and dispersants to the mix, making marine oil snow that is can be toxic to organisms in deep-sea ecosystems.

Gossipthe NHMFl every year, to conduct experiments with higher-intensity fields than can be achieved in a typical lab.

Nature, 12 June 2019

http://www.nature.com

Consequences of Deepwater Horizon oil spill2019-06-17If you were able to stand on the bottom of the seafloor and look up, you would see flakes of falling organic material and biological debris cascading down the water column like snowflakes in a phenomenon known as marine snow. Recent disasters like the Deepwater Horizon oil spill in the Gulf of Mexico, however, have added a new element to this natural process: oil. During these events, the natural marine snow interacts with oil and dispersants to form what’s known as marine oil snow as it sinks from the surface through water column to the seafloor sediments. The danger with marine oil snow is that it transfers oil and its negative impacts from the water column to the sediments on the bottom of the seafloor, delivering a more diverse suite of oxygenated compounds to sediments and deep-sea ecosystems. These oxygenated forms of many oil compounds are more toxic to organisms in the sediments than are the non-oxygenated forms. While this result may lessen the impact on near-surface organisms like fish and birds and shellfish, it transfers the oil to the deep ocean where it impacts fauna, deep corals, and fish down there, where adverse impacts were documented after the Deepwater Horizon oil spill. The university of Delaware’s Andrew Wozniak conducted research to investigate the fate and accumulation of marine oil snow in the Gulf of Mexico, the results of which were recently published in the Environmental Science and Technology journal. Wozniak, assistant professor in the School of Marine Science and Policy in uD’s College of Earth, Ocean and Environment, conducted the research while a research faculty member at Old Dominion university. He said that to recreate the conditions of the Gulf of Mexico, he and his collaborators used 100-liter glass tanks filled with seawater collected from the Gulf. In addition to the seawater, they added plankton collected from coastal waters directly before the initiation of the experiment. They also added the kind of oil spilled during the Deepwater Horizon disaster, along with the chemical dispersant used to break it up, and monitored the tanks for four days. Particles in the tanks formed on the surface, in the water column and the rest sank to the bottom. Wozniak collected the particles that sank and isolated the oil component to conduct a chemical analysis. When they performed the chemical analysis

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Gossipand compared it to the initial oil, the samples differed in a way that could be attributed to microbial degradation. Wozniak said this occurred as the marine oil snow sank through the water column. When an event like an oil spill occurs, the phytoplankton and bacteria in the ocean interact with the oil -- which is bad for them -- and they release extracellular polymeric substances (EPS) which collects the oil. “It’s kind of a defence mechanism and because that EPS is sticky, it gets that oil aggregated and hopefully protects them from the oil,” said Wozniak. The result of the EPS protection is a base particle for other substances to glom onto. “If something with enough density like minerals form on it, then they’ll sink and that’s when you get that marine oil snow,” said Wozniak. By looking at the degraded material at the bottom of the mesocosms, Wozniak could see that as the oil sank through the water column, it provided a microhabitat for microbes and microbes that prefer hydrocarbons and oil-like compounds proliferated. In addition to supporting that community of bacteria, it also keeps a portion of oil that has been changed -- potentially for the worse -- in the ocean. “It may have consequences for the toxicity of the oil because it oxygenates compounds,” said Wozniak. “The oxygenated forms of some of the compounds, like Polycyclic Aromatic Hydrocarbons, tend to be more toxic and so it may have important implications for future study for what’s happening in sediments or deep coral reefs.” The research was supported by a grant from the Gulf of Mexico Research Initiative to support consortium research entitled the Aggregation and Degradation of Dispersants and Oil by Microbial Exopolymers (ADDOMEx) Consortium.

Science Daily, 11 June 2019

http://www.sciencedaily.com

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Harvard Univer-sity chemists have achieved what a new paper calls a “landmark in drug discovery” with the total synthesis of halichondrin.

Chemists’ breakthrough in synthesis advances a potent anti-cancer agent2019-06-18It’s a feat three decades in the making: Harvard university chemists have achieved what a new paper calls a “landmark in drug discovery” with the total synthesis of halichondrin. Known to be a potent anti-cancer agent in mouse studies, and found naturally in sea sponges—though only ever in minuscule quantities—the halichondrin class of molecule is so fiendishly complex that it had never been synthesised on a meaningful scale in the lab. Researchers led by Yoshito Kishi, Morris loeb Professor of Chemistry, Emeritus, in Harvard’s Department of Chemistry and Chemical Biology, have now synthesised sufficient quantities of E7130, a drug candidate from the halichondrin class, to enable for the first time rigorous studies of its biological activity, pharmacological properties, and efficacy, all conducted in collaboration with researchers at Japanese pharmaceutical company Eisai. The molecule has undergone unusually rapid development and is already being tested in a Phase I clinical trial in Japan, under a license from Harvard’s Office of Technology Development (OTD) to Eisai. The company hopes to begin a second clinical trial in the united States in due course. The Kishi lab’s results, driven to completion through an intense, three-year research collaboration with Eisai, are published today in Scientific Reports, an open-access Nature journal. The paper reports the total synthesis of the highly potent halichondrin molecule E7130—11.5 grams of it, with 99.81% purity—and characterizes its mode of action. In preclinical studies, the research team has identified it not only as a microtubule dynamics inhibitor, as was previously recognized, but also as a novel agent to target the tumour microenvironment. “We spent decades on basic research and made very dramatic progress,” says Kishi, whose laboratory has, since 1978, received significant and sustaining support from the National Cancer Institute (NCI) of the National Institutes of Health to study the synthesis of natural products. The structure of the complete E7130 molecule derived by total synthesis is particularly challenging to replicate because it has 31 chiral centres, asymmetrical points that must each be correctly oriented. In other words, there are roughly 4 billion ways to get it wrong. When the natural product was first identified 33 years ago by Japanese researchers, it sparked immediate interest. “At that time, they realized the halichondrins looked exceedingly potent,” recalls Takashi Owa, Ph.D., Chief Medicine Creation Officer and Chief Discovery Officer for Eisai’s oncology business group, and a co-author of the paper. Over time, NCI investigators testing tiny amounts of it recognised that it was affecting the formation of microtubules, which are essential to cell division. “Due to the

Curiosities

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Curiositiesvery unique structure of the natural product, many people were interested in the mode of action, and the investigators wanted to do a clinical study,” Owa explains, “but a lack of drug supply prevented them from doing it. So, 30 years have passed, very unfortunately, but Prof. Kishi is a pioneer in this field.”

Over the years, the Kishi lab advanced methods of convergent synthesis, which enables complex molecules to be assembled from subunits, rather than constructed linearly. Another innovation, now known as the Nozaki-Hiyama-Kishi reaction, protected the highly reactive functional groups while they were being assembled. And in 1992, Kishi and colleagues achieved the first total synthesis of a halichondrin molecule (halichondrin B). The process required a sequence of more than 100 chemical reactions and produced less than a 1% overall yield. It was a major achievement, however, and a simplified version of that molecule, eribulin, became a drug to treat metastatic breast cancer and liposarcoma, now marketed by Eisai. Since then, Kishi’s lab has been engaged in basic research on organic synthesis, including discovery and development of new reactions usable at a late stage of synthesis. “In 1992, it was unthinkable to synthesize a gram-quantity of a halichondrin,” Kishi says, “but three years ago we proposed it to Eisai. Organic synthesis has advanced to that level, even with molecular complexity that was untouchable several years ago. We are very delighted to see our basic chemistry discoveries have now made it possible to synthesise this compound at large scale.” “It’s a really unprecedented achievement of total synthesis, a special one,” says Owa. “No one has been able to produce halichondrins on a 10-gram scale—one milligram, that’s it. They have completed a remarkable total synthesis, enabling us to initiate a clinical trial of E7130.” The team’s Scientific Reports paper describes the results of studies conducted in vitro and in vivo, in animal models, that shed light on the molecule’s complex mode of action. The team showed that E7130 can increase intratumoral CD31-positive endothelial cells and reduce alpha-SMA-positive cancer-associated fibroblasts, components of the tumour microenvironment that may be involved in the transformation to malignancy. “Prof. Kishi’s expertise provided us with such an exciting and unique opportunity to test the molecule in our systems,” says Owa. “I have never experienced this kind of very efficient and rapid, successful collaboration. Just a three-year collaboration took this from the discovery stage to the clinical development of such a complex molecule, having a very unique mechanism and mode of action. To me this is a kind of track record in drug development.” “The collaboration between scientists at Eisai and Harvard is an example of academia and industry working together successfully to accelerate the development of a new class of

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Drinking alcohol while pregnant can have a devastating impact on the developing baby, leading to poor cogni-tion and behaviour.

Curiositiestherapeutics that may address important unmet medical needs,” says Vivian Berlin, Managing Director of Strategic Partnerships in Harvard OTD. “The collaborative spirit and transparency of the relationship contributed enormously to the success of the project.” “Without OTD,” Owa adds, “this collaboration could never have happened. Harvard OTD has been a core for bridging industry and Harvard researchers, and facilitating discussions about how to build a win-win relationship.”

Phys.org, 17 June 2019

http://phys.org

Drinking alcohol at conception shown to harm rats – new study2019-06-18Drinking alcohol while pregnant can have a devastating impact on the developing baby, leading to poor cognition and behaviour. Alcohol is also known to increase the risk of miscarriages, stillbirth and other placental complications. But what if a mother drinks before she knows she is pregnant? Health guidelines in the uK, uS and Australia say it’s best to avoid alcohol throughout pregnancy. But this advice is offered with caution because of the lack of scientific evidence, so it is quite common for women to dismiss it. A 2016 study found that up to 30% of Australian women drank alcohol in the early stages of pregnancy. The same study showed that 18% of women drank in binge quantities (five or more standard alcoholic drinks in one session) before they found out they were pregnant. Since about half of pregnancies, worldwide, are unplanned, and most women stop drinking after they find out that they’re pregnant, many babies could be exposed to alcohol early in pregnancy. We just don’t know what harm drinking around the time of conception might cause, so our new study in rats aimed to find out. The study, published in Development, found that giving female rats alcohol in the very early stages of pregnancy can cause the foetuses to grow poorly. For the study, which I was involved in while at the university of Queensland, we gave female rats alcohol just before and after conception. The timing in pregnancy to humans relates to the week before conception and the first week of pregnancy. This is even before any of the baby’s organs have formed. While there are many differences between rats and humans, the period around conception is very similar. This first week of pregnancy is important for the development of the embryo. The embryo’s genes start to express their own proteins and they form a placenta, which is needed to maintain a pregnancy. This makes it a sensitive time in pregnancy as the genetic program that controls the

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As if waiting in line weren’t bad enough, travellers also worry about their radiation exposure.

Curiositiesbaby’s growth is susceptible to environmental changes. Our research shows that alcohol can stunt the growth of the early embryo and the stem cells that become the placenta. After the rats were exposed to alcohol, the placenta was poorly formed and was not able to give the foetus all the nutrients it needed to grow. This effect was more severe in female foetuses than male foetuses. The foetuses exposed to alcohol were also much smaller than those that didn’t receive any alcohol. This is a really important result, as human babies that are born small are at greater risk of diseases such as type 2 diabetes and high blood pressure in later life. They are also more likely to be obese. These diseases are not only detrimental to human health they are also a great burden to the public health system. Knowing how they are caused can inform public health policy and help prevent them. Our latest study shows that the effects of alcohol on the embryo were due to a decrease in the amount of choline – an important nutrient. Choline is an essential nutrient, which means it is needed for the body to function normally. The liver makes small amounts, but most choline is obtained through your diet. Choline is found in foods such as beef liver, soybeans, eggs, broccoli and spinach. Studies have shown that a higher dietary intake of choline around the time of conception is associated with a lower risk of neural tube defects in the baby. Neural tube defects, such as spina bifida, are abnormalities that occur in the development of the spinal cord and brain. The next step for scientists at the university of Queensland in this research study is to give rats supplemental choline to see if it prevents the negative effects of alcohol during pregnancy. If it works, it might be a useful supplement for women who drank alcohol around the time of conception.

Authors: Jacinta Kalisch-Smith-Postdoctoral Researcher, university of Oxford and Karen Moritz- Professor, The univeristy of Queensland, The university of Queensland

The Conversation, 11 June 2019

http://www.theconversation.com

Is the Radiation from Airport Body Scanners Dangerous?2019-06-18What do granite countertops, bananas and airports have in common? They’re all emitting low-level radiation — constantly. Yet, according to toxicologists, people aren’t coming into their offices with concerns about their kitchen renovations. Instead, just one of these sources is a cause

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Curiositiesof disproportionate anxiety: the security scanners in airports. Patient concerns are often based on the warnings health care providers have issued regarding medical X-rays. The Food and Drug Administration cautions patients to undergo X-ray imaging only when strictly necessary. But should people also be concerned about the security scanners at airports? luckily for health-conscious frequent fliers, there’s no need to worry, said Dr. lewis Nelson, professor and chair of emergency medicine at Rutgers New Jersey Medical School. Radiation is a general term for different kinds of moving electromagnetic energy: ionizing radiation (what X-ray machines emit) and non-ionising radiation (which includes radio and magnetic waves). The key difference between ionising and non-ionising radiation is the level of energy they transmit. Ionising radiation has enough energy to knock electrons away from atoms, creating free radicals; these chemically reactive particles can damage DNA and increase people’s risk of cancer. But ionising radiation has a real impact on our health only when received at high doses. And in airport X-ray machines, even though about half of the scanners emit ionising radiation, the dose just isn’t high enough to do bodily harm, Nelson said. (Roughly half of scanners use millimetre waves, a form of non-ionising radiation.) “It’s so tiny that it’s inconsequential,” he told live Science. While patients may be right to be concerned about the number of medical X-rays they receive, the amount of radiation delivered by an airport X-ray is tiny in comparison. A chest X-ray exposes patients to roughly 1,000 times the radiation of an airport scanner. The Health Physics Society estimates that airport X-ray scanners deliver 0.1 microsieverts of radiation per scan. In comparison, a typical chest X-ray delivers 100 microsieverts of radiation, according to a 2008 study published in the journal Radiology. And travellers are exposed to far more radiation on the flight itself, Nelson said. Every minute on a plane delivers roughly the same dose of radiation as one airport X-ray scan. “It’s ironic that people afraid of radiation exposure in screening don’t have any qualms about getting on the airplane,” Nelson said. These scanners emit such a tiny amount of radiation that even if you flew every day for a year, you’d still receive only a fraction of the ionising radiation you absorb from food, based on dose estimates from NASA. Most food contains small amounts of the radioactive molecules carbon-14 and potassium-40, according to NASA. In fact, many of the objects and substances we encounter daily emit radiation; the soil, cement sidewalks and buildings, and even the air we breathe are all slightly radioactive. Compared to all that radiation, an X-ray scanner emits an insignificant amount, Nelson said. That holds true even for people more vulnerable to radiation exposure, such as pregnant women and babies, who receive the same amount of background radiation daily as anyone else. “The dose makes the poison,”

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Dangerous chemi-cals used to create non-stick cookware and fire-fighting foams are showing up in our food.

CuriositiesNelson said, “Everything is toxic if you have enough of a dose. The corollary to that is everything’s nontoxic if you have a low enough dose.” And in this case, Nelson added, airport X-rays definitively fall on the nontoxic side of the spectrum.

live Science, 8 June 2019

http://www.livescience.com

What Are ‘Forever Chemicals’ And How Are They Getting in Your Food?2019-06-18A recent analysis by the u.S. Food and Drug Administration (FDA) found chemical contamination of PFAS (Per- and polyfluoroalkyl substances) at multiple levels of the u.S. food supply chain. However, the agency maintains that their findings don’t represent a likely health concern for consumers.

What are PFAS and why are they used?

PFAS are a widely used class of nearly 5,000 synthetic chemicals that have been used in manufacturing since the 1940s. They’re oil-, water-, and heat-resistant, making them profoundly useful and popular in all manner of products. These are the chemicals that make carpets stain resistant and fast food packaging able to repel grease and water. They’re also used in fire-fighting foams and what gives nonstick cookware, well, it’s non-stickiness. And dental floss contains them, too. They’re also known as “forever chemicals,” because the molecular bonds that form them can take thousands of years to degrade, meaning that they accumulate both in the environment and in our bodies. So, when images of an FDA presentation came to light last week, they appeared to confirm what many doctors and scientists have thought for some time.

PFAS are everywhere, even in food

FDA scientists sampled a wide variety of food sources across the country, including some taken directly from geographic areas known to have PFAS contamination. The milk at a dairy farm in New Mexico was deemed to be a potential human health hazard after being contaminated by PFAS in groundwater. leafy green vegetables like lettuce, kale, and cabbage grown downstream from a PFAS production plant in North Carolina and sold at a local farmers were found to contain the chemicals as well, but at low levels. The FDA did not deem them a human health concern. Additionally,

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CuriositiesPFAS were found in 14 out of 91 samples of meat, dairy, and grain samples, including off-the-shelf chocolate cake.

Reason for concern?

Despite what the findings seem to imply — that PFAS are widespread throughout the u.S. food-supply chain at various levels from production to packaging — the FDA’s consensus is optimistic. “Our findings did not detect PFAS in the vast majority of the foods tested. In addition, based on the best available current science, the FDA does not have any indication that these substances are a human health concern, in other words a food safety risk in human food, at the levels found in this limited sampling,” the FDA said in a statement released today. However, those sentiments don’t appear to be shared by other experts in the field of public health. “It’s certainly not a surprise in the sense that it’s long been known that the general population is exposed to these chemicals. Essentially everyone in the u.S. has these chemicals in their bodies. We’ve known that for a long time,” said Dr. Ken Spaeth, chief of occupational and environmental medicine at Northwell Health in New York. “My concern is that these particular FDA researchers concluded that these were safe levels, that there were no hazards posed by these levels, and I would take issue with that,” Dr. Spaeth said. He argues that looking at individual PFAS levels in chocolate cake and cabbages loses sight of the “big picture” of PFAS, which is about cumulative, lifetime exposure. In other words, it’s about the PFAS levels that are in everything from the water we drink to the furniture in our house rather than just what’s found in that box of chocolate cake on store shelves.

How PFAS can affect health

PFAS are recognised as having the potential to cause a host of serious health problems, including cancers, liver and kidney problems, reproductive harm, high blood pressure, and thyroid issues. The strongest evidence of such adverse health effects comes from an epidemiological study known as the C8 Health Project, which took place from the 1950s until 2002 in areas of known water contamination in West Virginia and Ohio. What still remains unclear is at what level of lifetime exposure do these health effects manifest. There are currently no federally-regulated safety levels for PFAS by the FDA or other federal agencies. In 2016, the Environmental Protection Agency (EPA) issued a health advisory for certain PFAS, which set a lifetime exposure limit for drinking water at 70 parts per trillion. However, health advisories are non-binding, non-enforceable limits that are instead meant to inform the public and health officials. “EPA

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Curiositiesdoes not anticipate a person to experience negative health effects if they drink water with levels of PFOA or PFAS (or both combined) at or below 70 ppt (parts per trillion) every day over their entire lifetime. The health advisories are based on estimated exposure from drinking water and household use of drinking water during food preparation (e.g., cooking or to prepare coffee, tea, or soup),” an EPA spokesperson told Healthline in an email. The spokesperson said that the limit set by the health advisory isn’t appropriate to identify the potential exposure risk of other products, including food sources like fish, meat, and dairy. Wendy Heiger-Bernays, PhD, a molecular toxicologist in the Department of Environmental Health at the Boston university School of Public Health, told Healthline that the FDA’s findings provide further proof that federal regulations need to be established across one or more agencies. “I think they need to be established very quickly. The evidence is sufficient to set limits,” she said. Dr. Heiger-Bernays is keenly aware of the potential danger of PFAS in the environment and our bodies because of her understanding of the special bonds that make them “forever chemicals.” “When you have these two atoms, carbons and fluorines, and they bind together molecularly, it creates a molecule that cannot be broken down by enzymes in the body, by sunlight, by microorganisms. They just can’t be broken down,” she said. “They are here forever.”

Some good news

Blood levels of certain PFAS have actually declined over the past two decades. In 2006, the EPA launched the PFOA Stewardship Program alongside the eight major companies of the PFAS industry including 3M and DuPont, to help phase out certain PFAS from manufacturing. But without any real regulation at the federal level, there’s little that individuals can do to mitigate their own exposure to PFAS because of how widespread they are throughout commercial and consumer goods. “It would require multiple agencies since no one arena is probably sufficient to ensure that exposures are adequately reduced. It would take a coordinated effort, which means there has to be political and regulatory focus for this to happen,” Spaeth said. “There doesn’t seem to be a critical mass of political will to get this done.”

Healthline, 12 June 2019

http://www.healthline.com

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Jul. 12, 2019

How a simple nudge can improve health and nutri-tion reporting.

CuriositiesHyped-up science is a problem. One clever Twitter account is pushing back.2019-06-18What do these three headlines, and many others like them, have in common? They were stories about studies conducted on mice. Now, there’s nothing particularly unusual about research that’s conducted on mice and not on humans. It’s safer and less expensive — a core part of the scientific process. And while for animal welfare reasons it’ll be great news when we find a better way to do invasive experiments, many of these experiments aren’t even hard on the mice. But overhyping preliminary results is a real problem in science reporting. In drug development, it’s a very long road from a promising mouse study to clinical trials in humans. In health and nutrition reporting, there’s still a lot of uncertainty about how much mouse findings are applicable to humans. Yet articles often lead with an exciting finding — a new chemical that treats cancer, a new diet that extends life spans — and mention only after many paragraphs that the study was conducted on mice, not on people. In April, behavioural scientist James Heathers decided to do something about it — something ridiculously simple. He made a Twitter account called “Just Says In Mice.” As promised, the Twitter account just retweets science articles, adding “IN MICE.” The Twitter account was an instant sensation; @justsaysinmice now has nearly 60,000 Twitter followers, many of whom bring bad science to Heathers’s attention. The tweets are pretty funny, but there’s a serious mission at the core. “I am perfectly prepared to judge your outlet, out loud and in public,” Heathers states in his mouse mission statement, “if you say ‘patients’ when you mean ‘genetically modified mice,’ likewise ‘women’ or ‘men,’ likewise when you say ‘cancer’ (as if that was a single condition anyway) when you mean ‘cancer in a specific mouse model,’ likewise when you say ‘obesity’ when you mean ‘fat mice.’ ” He argues that misleading the public like this has real consequences. “When it comes to reporting on science, I feel like this attitude is slowly, imperceptibly, contributing to an erosion of trust, because we’re continually betraying what’s we’ve done and what’s possible to do.” And his little mouse account is well-positioned to fix this. Journalists are disproportionately on Twitter — it’s a major tool for networking, sharing stories, and contacting sources. Endless think pieces have been written about whether journalists are too beholden to Twitter, and debated at length on, well, Twitter. So @justsaysinmice isn’t just making fun of bad reporting — it is also highly visible to almost all the science reporters who provide fodder for it. And there are some signs that they’re changing their behaviour. When I covered efforts to make vaccines that don’t need to be refrigerated last week, I had @justsaysinmice on

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“These refined carbohydrates could be feeding the bad bacteria in the small intestine,” said researcher Marit Zinocker, “and that’s where inflam-mation starts.”

Curiositiesthe mind: The mice were only needed to test that the vaccines — which have been tested extensively in humans — hadn’t lost any potency, so the experiment’s relevance to humans was easier to establish. Nonetheless, I spent a paragraph explaining this when I otherwise might not have. Heathers writes of his mouse account that he has been flooded with examples of mouse study reporting, both good and bad: I continually get mouse-related communication now. No complaints, obviously I signed up for that. However, it’s giving me the distinct impression that @justsaysinmice is... well, it’s working. Mice seem to be appearing in headlines, ledes, and tweets at a higher rate. It’s easy for him to be wrong about that (as he acknowledges) — after all, being at the centre of the national mouse-reporting conversation will definitely give you a skewed impression of the state of science reporting. But it’s pretty plausible to me that he’s right. The behaviour change he’s asking for is pretty simple: mention clearly, and upfront, that the research was conducted in mice. And (since there are now so many people scouring the internet for bad mouse reporting) the consequences if you forget are very predictable: a two-word public scolding from a popular science account. That seems like a set of conditions that might produce real improvements. So next time you see an article that’s clear that the research it’s reporting on was conducted on mice, you might want to thank this odd, well-intentioned little social experiment. And next time you see an article that isn’t upfront about its mice, let Heathers know. It’s for science.

Vox, 15 June 2019

http://www.vox.com

Processed foods are a much bigger health problem than we thought2019-06-18The case against processed food just keeps getting stronger. But, amazingly, we still don’t understand exactly why it’s so bad for us. In two new papers published in the BMJ, the more ultraprocessed — or industrially manufactured — foods a person ate, the more likely they were to get sick and even die. In one study, they were more likely to suffer from cardiovascular problems. The other linked an ultraprocessed diet to a higher risk of death from all causes. Those studies followed a first-of-its-kind randomised controlled trial, out of the National Institutes of Health: Researchers found people following an ultraprocessed diet ate about 500 more calories per day than those consuming minimally processed, whole foods. Sure, potato chips, cookies, and hot dogs are chock-full of

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Curiositiessalt, sugar, fat, and calories. They can cause us to gain weight and put us at a higher risk of diseases such as diabetes and obesity. But why? What if there’s something unique about ultraprocessed foods that primes us to overeat and leads to bad health? A new, intriguing hypothesis offers a potential answer. Increasingly, scientists think processed foods, with all their additives and sugar and lack of fibre, may be formulated in ways that disturb the gut microbiome, the trillions of diverse bacteria lining our intestines and colon. Those disturbances, in turn, may heighten the risk of chronic disease and encourage overeating. The idea sheds new light on why ultraprocessed foods seem to be so bad for us. But to understand the hypothesis, we need to first look at what ultraprocessed foods are, and how they shape the community of bacteria in our gut that’s so intimately linked to our health.

ultraprocessed foods, explained

More than half of the calories Americans consume now come from ultraprocessed foods. But what exactly are they? For starters, ultraprocessed foods look a lot different from the foods our great-great-great-grandmothers ate, as author Michael Pollan would say. They’re the frozen chicken nuggets at McDonald’s, the soda and sports drinks in just about every beverage fountain across the country, and the milkshakes masquerading as coffee at Starbucks. According to a widely used scientific definition, they’re: industrial formulations made entirely or mostly from substances extracted from foods (oils, fats, sugar, starch, and proteins), derived from food constituents (hydrogenated fats and modified starch), or synthesised in laboratories from food substrates or other organic sources (flavour enhancers, colours, and several food additives used to make the product hyper-palatable). In other words, ultraprocessed foods are created in factories. They’re pumped full of chemicals and other additives for colour, flavour, texture, and shelf life. This processing generally increases the flavour and caloric density of the foods, while stripping away the fibre, vitamins, and nutrients. So, these foods are distinct from whole foods (like apples and cucumbers) and processed foods (like vegetables pickled in brine, or canned fish in oil) that rely on only salt, sugar, and oil — rather than a range of complicated additives — to preserve them or make them tastier. Carlos Monteiro, a professor of nutrition and public health at the university of Sao Paulo, helped write the “ultraprocessed” definition in 2009, when he was working with the Brazilian government to understand how the emergence of a global industrial food system changed Brazilians’ eating habits. People started cooking less, eating out more, and relying on packaged products for

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Curiositiestheir calories. “We realised that people were replacing freshly prepared dishes and meals,” he told Vox, “[with] ready-to-consume products based on sugar, fats and salt plus many ingredients of exclusive industrial use,” such as protein isolates, modified starches, and colour additives. That’s why pinpointing exactly what in ultraprocessed foods may increase the risk of disease is difficult. It’s hard to disentangle, for example, whether it’s the chemical additives in these foods, the calories they deliver, or the stuff they generally don’t contain, such as fibre. Or maybe it’s the contaminants in them, like plastics that leach from packaging. People who eat lots of processed foods may also be fundamentally different from people who avoid them. “We are dealing with something very complex,” Monteiro added.

What we eat shapes our gut flora

Considering the arrival of ultraprocessed foods fundamentally changed how we eat; researchers recently began to wonder what that was doing to our gut microbiome. The majority of bacteria in our gut are benign or good for our health. They evolved with us to do things such as aid digestion and regulate the immune system. We’re only just beginning to understand how integral the microbiome is to our health. And to date, much of the science on the relationships between these bacteria and our health is focused on mice. Of the studies we have in humans, most of the findings are correlational. But there’s one thing researchers already agree on: “Diet is the No. 1 influencer and determinant of our gut microbiome composition,” said Suzanne Devkota, director of microbiome research at the Cedars-Sinai F. Widjaja Foundation Inflammatory Bowel and Immunobiology Research Institute. They also generally agree that the more diversity of bacteria in the gut microbiome, the better for our health. Devkota is among the researchers exploring how the influx of processed meats, cereals, and sugars into our diet has influenced both the type of bacteria and variety of them in the microbiome. Their findings are potential cause for concern. When researchers have compared the microbiomes of mice eating a bland, low-fibre, high-fat diet (one that resembles Western-style, ultraprocessed food) to mice eating a fibre-enriched high-fat diet, the two sets of rodents had distinctly different microbiomes: Mice on the low-fibre diet had a marked reduction in the total numbers of bacteria in their gut and a less diverse microbiome compared to the mice on the high-fibre diet. The mouse findings echo the few studies we have in humans. Researchers who analysed stool samples from people living in less industrialised hunter-gatherer cultures — where ultraprocessed foods are uncommon — and compared them

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Curiositieswith stool samples from people in industrialised countries, uncovered a strong pattern: The further away people were from industrialisation and ultraprocessed foods, the more diverse their gut micriobiome was. Similarly, when researchers sequenced the DNA of calcified dental plaque, they found the bacterial colony in the oral cavities of humans from Neolithic and medieval times were a lot more diverse than postindustrial modern humans. “Major changes in carbohydrate intake in human history appear to have impacted the ecosystem of the mouth,” the researchers wrote. “The thing you can generally say is that in states of health, the microbiota has a high level of diversity in a wide variety of different species,” said Andrew Gewirtz, a professor at Georgia State university’s Centre for Inflammation Immunity and Infection. “And a lot of these [bacteria] tend to get lost in diets that are highly processed.”

The possible problem with emulsifiers and refined sugars in junk food

There’s also a link between diets heavy in ultraprocessed foods and harmful inflammation — when the body’s inflammatory response goes into overdrive, making it harder to fight off viruses and disease. One measure of inflammation is a blood marker called C-reactive protein (CRP). Researchers have found associations between higher levels of CRP and various chronic illnesses, including cancer, arthritis, cardiovascular disease, and diabetes. And people who eat an unhealthy diet tend to have higher levels of CRP in their bodies. So, why exactly are these foods linked to less diversity in the microbiome, and more inflammation and disease? One theory: Key ingredients, such as emulsifiers and refined sugars, impair the microbial life in our gut, instead of helping it flourish. Emulsifiers are additives used to stabilise ultraprocessed foods. They help the oil and vinegar in a bottled salad dressing stay mixed, and keep ice cream from forming ice and crystallising in the freezer. For a study that was published in 2015, Gewirtz and his colleagues hypothesised that widely used emulsifiers — specifically carboxymethylcellulose and polysorbate-80 — might disturb the microbiome and increase inflammation. And that’s exactly what they found. Mice that had a genetic predisposition to colitis, a chronic, inflammatory bowel disease, developed the disease faster when exposed to emulsifiers. Mice that didn’t have that predisposition but were also emulsifier-exposed developed low-grade inflammation and mild obesity. Gewirtz said he thinks the friendly microbes in the gut may view emulsifiers as a toxic chemical that “antagonises” the microbiome and causes it “not to live well with the host.” “As best we can tell, at doses that seem to be reasonable mimics of exposure to emulsifiers in humans, the emulsifiers promoted inflammatory diseases in mice,” said Gewirtz, who

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Curiositiesis now working on a similar study in humans. But the mouse evidence was compelling enough that forthcoming dietary recommendations for inflammatory bowel disease suggest people avoid emulsifiers. Another theory, outlined in a recent review paper on the effects of the Western diet on the microbiome, is that the sugar in ultraprocessed foods may feed harmful bacteria in the gut, causing them to bloom. “These refined carbohydrates could be feeding the bad bacteria in the small intestine,” said the paper’s lead study author, Marit Zinocker, “and that’s where inflammation starts. Animal studies have shown that if you increase the amount of simple sugars in the diet, that’ll change the growth potential of [pathogenic] bacteria in the gut.” Zinocker emphasised that the emulsifier and refined carbohydrate hypotheses are just two potential explanations for why ultraprocessed foods are unhealthy — and there’s still a lot of scientists have to learn. For now, though, researchers have figured out that it’s not just what’s added to processed foods that may hurt the gut microbiome. It’s also what’s missing.

The lack of fibre in ultraprocessed foods may harm us too

Because our intestines can’t directly digest fibre, we’ve long seen fibre as beneficial for relieving constipation by adding bulk to stool and promoting regular bowel movements. But that “was before people [realised] how much the non-digestible things we eat impact our gut bacteria,” said university of Michigan microbiologist Eric Martens when I spoke to him for a feature on fibre. Researchers now consider fibre’s role in nourishing our gut microbiome to be one of its main health benefits. They don’t yet fully understand why fibre is so good for our gut, but they have some ideas. Fermentable fibres, which include all soluble fibres and some insoluble fibres, are metabolised or fermented by bacteria in the gastrointestinal tract. That process produces chemicals, including short-chain fatty acids, that are important food sources for our gut bacteria. They also carry health benefits, Martens said. Short-chain fatty acids have been shown to promote insulin production so we can better manage the spikes of sugar (or glucose) in our blood, for example, helping to manage Type 2 diabetes. In addition, they seem to have anti-inflammatory properties. “When we don’t consume enough fibre, we are essentially starving our gut microbiome,” Jens Walter, a researcher who studies fibre at the university of Alberta, told me, “which is likely detrimental for a variety of reasons. We also probably lose [microbiome] diversity.” That lack of diversity linked with a low-fibre diet might affect the mucus layer in the gut. Mucus acts as a protective barrier between us and the outside world. It’s constantly being replenished by secretions from the cells that make up our intestines, and

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Curiositiesit’s covered with a layer of bacteria, part of our microbiome. Fibre feeds the bacteria on top of the mucus layer as it passes through, helping keep our microbiomes robust, Gewirtz said. Another fibre study, again in mice, showed what happens when the bacteria in the digestive tract don’t get any fibre. Researchers, including Martens, found the bacteria begin to eat away at the mucus layer, bringing them into closer contact with the intestinal tissue. “The hypothesis is if we stop feeding the microbiome [fibre], the bacteria will resort more frequently to digesting that mucus barrier as a source of nutrients.” If bacteria eating up the mucus layer sounds bad, well, it is. The mucus layer keeps out pathogens, and the researchers were able to show that if they introduced a pathogen in the context of a low-fibre diet, it had an easier time getting into the intestine and causing an infection. “The lack of a mucus barrier made the disease get much worse much quicker,” Martens added. “It may irritate the [intestinal] tissue or provoke immune responses,” leaving the mice more vulnerable to disease.

Why microbiome disturbances may cause people to eat more

The microbiome idea may also help explain why highly processed diets cause people to eat more, Gewirtz said. “Antagonising the microbiota by highly processed diets — starving it by removing fibre and attacking it [with emulsifiers] — promotes inflammation.” That can hamper the body’s ability to feel satiated and result in overeating. For example, he explained, eating causes the body to release the hormone leptin, which quells hunger. But inflammation interferes with leptin’s action. “Put another way, our results do not question the notion that the obesity epidemic is driven by overeating,” he added. “Rather, it suggests that such overeating is driven, in part, by alterations in the microbiome inducing inflammation.” Researchers still have a lot to untangle here. But should we wait to better understand precisely why ultraprocessed food is bad for us before we start regulating it? Brazil’s Monteiro thinks lawmakers should act now and figure out how to make unprocessed foods more accessible and affordable, while taxing ultraprocessed foods and regulating the marketing around them. “We started to have policies to make people smoke less or to avoid smoking before we knew all the problems caused by smoking,” he said. Similarly, with ultraprocessed foods, he argued, health authorities shouldn’t wait until every mechanism is known. “We’re in a situation where you have so many ultraprocessed foods and so many diseases related to ultraprocessed foods,” Monteiro said. If we try to answer every question about these products, we’ll never regulate them. And given the mounting

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Several popular breakfast foods, including Cheerios and Nature Valley products, continue to test positive for trace amounts of a contro-versial herbicide that may increase the risk of cancer, according to a report released by an environmental advocacy group.

Curiositiesevidence of harm, delayed action increasingly looks like it’ll cost health dollars and lives.

Vox, 11 June 2019

http://www.vox.com

Many breakfast cereals still contaminated by weed killer, environmental group says2019-06-18Several popular breakfast foods, including Cheerios and Nature Valley products, continue to test positive for trace amounts of a controversial herbicide that may increase the risk of cancer, according to a report released by an environmental advocacy group. The Environmental Working Group, which has links to the organics industry, found that all 21 of the products it tested had levels of glyphosate that were “higher than what EWG scientists consider protective for children’s health.” Manufacturers maintain that their foods are safe, and the findings aren’t unprecedented: The group also found in October that most of the breakfast cereals it tested contained glyphosate, the main ingredient in the weed killer Roundup. The new report follows two prominent legal verdicts that determined the herbicide caused cancer in plaintiffs.

Juries say glyphosate causes cancer, award billions

A federal jury unanimously determined in March that Roundup was a “substantial factor” in causing a California man’s cancer. And last month, California jurors ordered the manufacturer, Monsanto, to pay over $2 billion to a couple who said long-term exposure to the product caused their cancers The latter verdict is being appealed, but about 11,000 similar cases are pending in state and federal courts. Pharmaceutical giant Bayer AG, which now owns Monsanto, maintains that its product is safe. A spokeswoman for the company’s crop science subsidiary, Charla lord, said that an “extensive body of science” and “the conclusions of regulators around the world” show that “glyphosate-based products are safe when used as directed.” General Mills, which manufactures all of the products tested in the EWG report, said in a statement that its “top priority is food safety.” The company noted that “most crops grown in fields use some form of pesticides and trace amounts are found in the majority of food we all eat” but said it was working to “minimise the use of pesticides on the ingredients we use in our foods.” General Mills did not directly respond

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Curiositieswhen asked why it is reducing pesticide use when it already considers its products to be safe.

How much glyphosate is too much?

An analysis published in February found that glyphosate can increase cancer risk by up to 41%, although the researchers focused on those with the “highest exposure” to the chemical, like groundskeepers, who are exposed to more glyphosate than people may consume through snacks. The herbicide can make its way into processed foods after being used on farms that grow oats, but none of the levels found in any food products in the new report exceeded the Environmental Protection Agency’s legal limits. “It is not surprising that very low levels of pesticides, including glyphosate, are found in foodstuff,” said Dr. Paolo Boffetta, associate director for population sciences at Mount Sinai’s Tisch Cancer Institute. “In general, these levels are unlikely to cause health effects in consumers.” Still, “it is important that people know whether there is glyphosate or other chemicals in their food, even at very low levels,” said Boffetta, who was not involved in the reports or the analysis. General Mills emphasised in its statement that it followed “strict rules” set by “experts at the [Food and Drug Administration] and EPA.” Bayer’s lord said “the reality is that regulatory authorities have strict rules when it comes to pesticide residues, and the levels in this report are far below the established safety standards.” The Environmental Working Group, however, uses a far more conservative health benchmark that includes an added buffer for children, as “exposure during early life can have more significant effects on development later in life,” said Dr. Alexis Temkin, an EWG scientist who co-authored both reports and spoke to CNN last year. Manufacturers dispute that threshold. In an October statement, General Mills said that “the extremely low levels of pesticide residue cited in recent news reports is a tiny fraction of the amount the government allows.” The EPA said in April that the proper use of glyphosate poses “no risks to public health” and that the chemical “is not a carcinogen,” a cancer-causing chemical. But a World Health Organization agency, the International Agency for Research on Cancer, determined in 2015 that glyphosate is “probably carcinogenic to humans.” A separate WHO panel assessing pesticide residues said in 2016 that “glyphosate is unlikely to pose a carcinogenic risk to humans from exposure through the diet,” adding to a dizzying array of contradictory findings, but the International Agency for Research on Cancer has vigorously defended its conclusion. The agency wrote in 2018 that it “has been subject to unprecedented, coordinated efforts to undermine the evaluation, the

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Curiositiesprogram and the organisation.” Those attacks, it said, “have largely originated from the agro-chemical industry and associated media outlets.”

A war of words

A 2017 CNN investigation of internal emails from Monsanto appeared to show company executives attempting to discredit the International Agency for Research on Cancer report before it was even released. One executive’s email, titled “RE: IARC planning,” suggested that the company ghost-write parts of a 2015 study in which experts rejected the agency’s finding that glyphosate could cause cancer. A Monsanto spokeswoman told CNN at the time that the study was not ghost-written and was “the work of the glyphosate expert panel.” Although the EPA has maintained that glyphosate is safe, CNN’s investigation also raised questions about industry influence at the federal agency. A Monsanto executive wrote in a 2015 internal company email, for example, that an EPA official offered to help quash another agency review of glyphosate, saying, “If I can kill this, I should get a medal.” The company has denied any undue influence over regulators. And its parent company, Bayer Crop Science, criticised the Environmental Working Group in its recent statement to CNN. “The group behind the new report has a long history of spreading misinformation about pesticide residues,” spokeswoman lord said. EWG, a non-profit organisation based in Washington, denied those allegations. Bayer’s criticism “must be taken with a grain of salt,” EWG President Ken Cook said in a statement. In light of lawsuits, he said, Bayer was “desperate to continue hiding the truth.” Though it maintains that it is an independent organisation, EWG acknowledges support from the organics industry, stating that its “corporate partners for general support and events” include Organic Valley and Stonyfield Farms. Foods labelled organic may not be grown with most synthetic substances, including glyphosate. The group also has a “shared services agreement” with the Organic Voices Action Fund, a non-profit organization funded by companies such as Nature’s Path and Annie’s -- both of which make cereal.

CNN News, 12 June 2019

http://www.cnn.com/health

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The highly potent pesticide DDT was banned more than a half-century ago, but the toxic chemical persists in lake ecosys-tems and continues to impact freshwater food chains, accord-ing to a new study.

CuriositiesDDT still affecting lake ecosystems 50 years after it was banned2019-06-18The highly potent pesticide DDT was banned more than a half-century ago, but the toxic chemical persists in lake ecosystems and continues to impact freshwater food chains, according to a new study. “What was considered yesterday’s environmental crisis in the 1950s through 1970s remains today’s problem,” Josh Kurek, an assistant professor in the department of geography and environment at Mount Allison university, said in a news release. “Decades of intense insecticide applications to our conifer forests have left a lasting mark on these lakes -- and likely many others in eastern North America.” Around the middle of the 20th century, forest stakeholders began using dichlorodiphenyltrichloroethane insecticides to combat pest outbreaks across North American forests. For more than two decades, the chemical was sprayed liberally from airplanes onto tree strands impacted by spruce budworm, a destructive conifer pest. Though applied to trees, DDT persists and eventually washed into watersheds. The chemical accumulated in lakes. Outcries over DDT’s harmful effects on wildlife led to its ban in 1972, but according to new research, the chemical is still hanging around in the environment. For the new study, scientists collected sediment samples from the bottoms of five remote lakes in north-central New Brunswick, Canada. Analysis of the lake bed sediment cores revealed, as expected, elevated levels of DDT trapped in layers dated to the 1960s and 70s. But researchers also measured significant levels of DDT and its toxic by-products in modern sediments. The levels of toxins persisting in modern sediments exceed the threshold for harmful biological effects, according to researchers. Scientists also measured a correlation between greater DDT levels and smaller water flea populations. Previous studies have linked reductions in water fleas to increased algae production and fewer prey for fish. “We have learned a lot of tough lessons from the heavy use of DDT in agriculture and forestry,” said Karen Kidd, professor at McMaster university. “The biggest one is that this pesticide was concentrated through food webs to levels that caused widespread raptor declines in North America. The lesson from our study is that pesticide use can result in persistent and permanent changes in aquatic ecosystems.” Researchers published their survey of DDT’s freshwater legacy this week in the journal Environmental Science and Technology.

uPI, 12 June 2019

https://www.upi.com

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Jul. 12, 2019

Air fresheners and fire retardants in sofas can add to pol-lution inside homes

CuriositiesTackle scourge of indoor air pollution, doctors urge2019-06-18The law must cover the quality of air indoors as well as outdoors, leading doctors have urged in a letter to the environment secretary. The Royal College of Physicians (RCP) and the Royal College of Paediatrics and Child Health (RCPCH) have urged the environment secretary to tackle the “cocktail” of pollutants that lurk inside our buildings. In a letter to Michael Gove, the doctors called for indoor air quality to be included in the forthcoming environment bill. “While pollutants in outdoor air are now known to be important contributors to multiple acute and chronic diseases, pollutants generated outdoors clearly gain access to the indoor spaces of our homes, schools and workplaces where we spend greater than 85 per cent of our time and where personal and household products add to the load,” they wrote. “This is an important source of pollutant exposure that must be recognised. “Air pollution, both outdoors and indoors, does not just contribute to adverse health statistics; there are innocent people suffering.” Including indoor air in the environment bill would “be a significant step forward in safeguarding public health for all our citizens”, the doctors wrote. The bill, which is still in draft form, aims to protect the environment after Britain leaves the European union. It currently refers only to the “natural environment”. Mr Gove has suggested that including indoor air would be an invasion of privacy. Toxic chemicals can leak out of furniture, carpets, paint and varnish, while others may be released by toiletries, air fresheners and cleaning products. The compounds, which include some fire retardants in sofas and phthalates in shampoo and food packaging, have been linked to a range of ailments, including asthma, allergies, heart and lung problems, cancer and reduced fertility. In 2016, the RCP and RCPCH calculated that air pollution cuts short 40,000 lives each year in Britain. Recent research suggests that the death toll is as high as 64,000. The Times is campaigning for a new bill to give everyone the right to an unpolluted atmosphere, in what would be the biggest change in air quality legislation in more than 70 years. Geraint Davies, chairman of the all-party parliamentary group on air pollution, which is also calling for the environment bill to venture indoors, said that the royal colleges’ intervention was “hugely significant”. “Air pollution is penetrating the buildings we live and work in, where it mixes with fumes from cleaning products, air fresheners, gas stoves and flame retardants before getting trapped behind our double glazing,” he said. “This toxic brew of pollution is linked to a range of health problems, including asthma and cancer, and contributes to the premature deaths of tens of thousands of people every year. “It is crucial that people’s right to breathe clean air is

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In 2015, the scien-tist’s husband was almost killed by an antibiotic-resistant superbug, until she found a cure that is now saving others

Curiositiesenshrined in the new environment bill. “If people have the right to breathe clean air outside, they have a right to clean air in their homes, schools and hospitals as well.” Stephen Holgate, who is leading a review of indoor air pollution by the RCP and is one of the letter’s signatories, said: “There is a complex relationship between indoor and outdoor air pollution and it does not make sense to treat them separately.”

The Times, 13 June 2019

http://www.timesonline.co.uk

Steffanie Strathdee: ‘Phages have evolved to become perfect predators of bacteria’2019-06-18Infectious disease epidemiologist Steffanie Strathdee’s husband survived a deadly antibiotic-resistant bacterial infection thanks to her suggestion of using an unconventional cure popular in the former Soviet union: fighting the bug with a virus. Now the global health expert at the university of California, San Diego, she has, along with her husband, Tom Patterson, who is also a scientist at the institution, written an account of their nine-month ordeal – The Perfect Predator: A Scientists’s Race to Save Her Husband from a Deadly Superbug.

What was the superbug your husband got, and how did he contract it?

It is called Acinetobacter baumannii but nicknamed Iraqibacter because many wounded service members who have returned from the Middle East were infected with it. It was once a wimpy bacteria – mundane and harmless – but its superpower is its ability to acquire antibiotic-resistant genes. It now tops the World Health Organization’s list of the 12 mostly deadly superbugs to human health. It has infiltrated clinics and hospitals all around the world and sticks to hospital linens. Tom likely picked it up in Egypt while we were vacationing there in late 2015 – sequencing later showed it was an Egyptian strain. He came down in Egypt with what turned out to be acute pancreatitis, caused by a gallstone blocking his bile duct. He could have got [the superbug] from the Egyptian clinic we got him to. It could also have come from the swirling red dust we were exposed to while exploring pyramids – the pathogen is also found in soil. We really don’t know. But the football-sized cyst that formed in his abdomen as a complication of the gallstone provided a nice little apartment for the superbug to settle in and fester.

What is phage therapy and how does it work?

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CuriositiesPhage therapy is the use of bacteriophages – viruses that attack bacteria – to treat infections. There are trillions and trillions of phages on the planet and they have evolved over millennia to become the prefect predators to bacteria. The phage latches on to and enters the bacterial cell where it takes over its machinery and turns it into a phage manufacturing plant. The newly minted phages then burst out and the bacterial cell dies. To work, phages have to be matched to the bacterial infection. But just how close the match needs to be depends on the bacterial species.

Phage therapy has been neglected in the west. Why?

Phages were first discovered in 1917 by a French-Canadian, Félix d’Herelle, but he had a hard time getting his work accepted – he wasn’t formally trained and was considered a vagabond scholar. Then, while phage preparations were being manufactured in the west up until the late 1930s, the scientific method hadn’t really been worked out. They were, for example, not being matched to specific bacteria and they were sold without being purified, so some actually could cause harm. After penicillin came to market in the early 1940s, phage therapy fell out of favour and political reasons kept it there. Former Soviet countries – where penicillin wasn’t so consistently available – had taken up phage therapy very vigorously. Western researchers and companies feared being labelled “pinko commie” sympathisers.

You got Tom out of Egypt and eventually into intensive care at your institution, uCSD. What turned you on to phage therapy and where did you find Tom’s phages?

We were running out of options to save Tom, whose infection had spread throughout his body, so I started exploring unconventional cures. I found a paper that mentioned phage therapy. Although I’d learned of phages in college, this was the first I had heard of using them as a treatment. My colleague Chip Schooley, chief of infectious diseases at the uCSD school of medicine, agreed it was an interesting idea and said if I could find phages that matched Tom’s bacterial infection, he would contact the Food and Drug Administration and get approval to use them for compassionate use. I knew what that meant: officially, Tom was dying. I began cold-emailing phage researchers asking for help. A phage researcher at Texas A&M university turned his lab into a kind of command centre, looking for phages active against Tom’s specific infection in his centre’s phage library and in sewage and barnyard waste – wherever you find a lot of bacteria is where you find the phages that kill them! He also wrote to researchers all over the world asking them to send any phages they had that might work,

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Curiositieswhich they did. But phages for Acinetobacter baumannii are very picky. Tom’s life depended on finding a match in time. In three weeks, which included a week spent on purification, a cocktail of four phages was ready to give to Tom. The navy – who our FDA contact also put us in touch with – produced a second four-phage cocktail from their phage library.

Did it work at once?

We began the intravenous phage therapy, but Tom’s bacteria quickly became resistant to all the phages except one in the navy’s cocktail. We didn’t realise that a lot of the phages across both cocktails were very similar to one another and were all trying to enter the bacteria by the same receptor. The bacteria’s successful attempt at evading one phage therefore offered resistance to the rest. luckily, looking again for more phages that would match, the navy found another in the murky waters of a sewage treatment plant in Maryland. From bog to bedside, so we say! It was powerful because it hit a different receptor. Coincidentally, we found there was synergy with one of the antibiotics Tom was getting. Tom woke up three days after we began the treatment and he fully cleared his infection within three months.

How did Tom’s case break new medical ground?

He was the first in the uS to get intravenous phage therapy for a systemic superbug infection. In the past when phage therapy has been used, it has usually been topically – sprinkled on somebody’s skin – or inhaled with a nebuliser. Going intravenous was really risky. Even in the former Soviet countries, where phage therapy has been used for decades, they don’t often treat intravenously because they don’t have the hi-tech capability to purify their phage of the bacterial debris that accumulates when you prepare them in large quantities, so there’s the risk of septic shock. We think of what Tom received as 21st-century phage therapy.

Since Tom’s case, you have assisted other patients to get phage therapy and you now, in addition to your day job, co-direct a new phage therapy centre at uCSD – the Centre for Innovative Phage Applications and Therapeutics – the first in North America. How many people have you helped to date?

After Tom’s case was publicised, people contacted me from all over the world wanting phage therapy. Strangers had helped us, and I felt I had an obligation to help them. So far, we’ve treated six other patients here at uCSD, and advised on a couple of dozen cases elsewhere across the uS and internationally. We haven’t always been successful, because

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Curiositiessometimes we have been contacted too late. But the FDA is now making it easier for people to get phage therapy earlier in the course of their infections. What’s needed now are clinical trials to see if it works on a broader scale.

I understand your centre helped in the case reported last month of the British teenager Isabelle Holdaway. She became the first person to be treated successfully with a genetically modified phage for a superbug infection following a double lung transplant.

Her mother had heard about Tom’s case and asked her uK doctor whether he could consider phage therapy. He contacted Schooley, the doctor who ended up treated Tom and now co-directs the centre with me. Isabelle’s infection – Mycobacterium abscessus – is in the same genus as tuberculosis and was fully resistant to antibiotics. She was receiving hospice care. The team asked a researcher with a mycobacterium phage library at the university of Pittsburgh to help, but most of the phages he found that matched were not predatory enough. So, they tweaked one genetically – clipping out a gene – to ensure it killed the bacteria rather than going dormant. The phage was administered intravenously, like with Tom, and Isabelle left the hospital in a week. I wept for joy. Isabelle is now finishing her A-levels and learning to drive.

Even if phage therapy is proven to work, is widespread use ever going to be achievable when it is essentially personalised therapy? How does it scale up?

What is needed are readily available phages to match whatever organisms we face in the bacterial world. Instead of having to resort to environmental sources every time – like we did in Tom’s case with the sewage – imagine a large, ever-expanding, open-source phage library that researchers and students contribute to from around the world, which could be accessible globally as a resource. Genetic tweaking is also clearly a way of expanding the range of bacteria that picky phages like Tom’s or Isabelle’s are able to attack.

What about the problem of the bacteria becoming phage-resistant?

Bacterial resistance to phage can be expected, but how quickly it occurs depends on a number of factors. In Tom’s case, it emerged fast. Isabelle has been treated for about a year and resistance hasn’t emerged yet, since her bacteria is slow-growing. And there are a few ways that issue can be overcome, like using a phage cocktail where different phages “hit” different

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Eating sea food near a coal-fired plant may affect your heart, lungs and kidneys

Curiositiesbacterial receptors. In the future, genetically modified or synthetic phages could be developed that are harder for bacterial resistance to overcome.

What’s your advice to people who do find their loved ones hospitalised with superbug infections? Shout for phage therapy?

For any serious illness, you need to be an advocate. Get educated about what’s going on and be actively involved in your loved one’s care. In the case of a superbug, understand what options are left in terms of antibiotics and also what kinds of side effects exist, because some last-resort antibiotics, like colistin, can be very hard on the body. Because phage therapy is experimental, you can’t necessarily get it if there are still antibiotic options available. If there are not, phage therapy may be possible. Email us.

The Guardian, 16 June 2019

http://www.guardian.com

Mercury-level high in marine foods sourced near coal-fired plants2019-06-18People living in a city with active coal-fired power plants and consuming local aquatic produce may have higher body levels of mercury, a study by the Indian Institute of Technology-Hyderabad has revealed. Researchers of the institute said they arrived at this finding after analysing the amount of mercury in the hair of over 600 people in three cities- Hyderabad, Nellore and Vasco da Gama, a press release said. The study has recently been reported in the Journal of Exposure Science and Environmental Epidemiology, a peer-reviewed public health journal, the release said. Mercury, a neurotoxin, is distributed in the environment and present in many products encountered in daily life. With wide circulation within and between ecosystems, the non-degradable liquid metal is used in industry and consumer products and exists as a natural impurity in ores, it said. The IIT-Hyderabad research team chose the three cities for their analysis Hyderabad, a city in the interior of the country with no specific local mercury source, Vasco da Gama, a city along the west coast, with again, no specific mercury source but probably more fish-eaters, and Nellore, a coastal city in Andhra Pradesh with several coal-fired power plants, it said. In modern times, the non-occupational exposure of humans to mercury comes from food, especially fish, and rice grown in contaminated fields, said associate professor, Department of Civil Engineering, IIT-Hyderabad,

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Forget 10,000 steps a day. Modern sports science and evolutionary biology now tell us how much exercise the human body really needs

CuriositiesAsif Qureshi, who heads the team of researchers. Coal-fired power plants are estimated to be the largest emitters of mercury to the atmosphere. The total mercury emissions in the country is estimated to be around 540 tonnes in 2020. In addition to neurotoxicity, mercury has also been implicated in adverse effects on lungs and kidneys, and heart diseases. “So, how much of mercury are Indians exposed to? This is a question we attempt to answer,” he said.

The Week, 12 June 2019

https://www.theweek.in

How many steps a day do you really need? Spoiler: It isn’t 10,0002019-06-18The Spine Challenger is a brutal race. It claws its way along the toughest 174 kilometres of the Pennines, the geological backbone of England, in the dead of winter. It must be completed in 60 hours. Finishers rack up some 5400 metres of ascent, equivalent to climbing Mont Blanc twice. Participants in 2017 – the fast ones, anyway – would have glimpsed Dom layfield, an irrepressibly upbeat man in his 40s, pulling away and disappearing into the low clouds and sleet. They let him go, perhaps thinking that this first-timer had underestimated the race’s difficulty and would burn out. They were wrong. After 28 hours of non-stop running and scrambling, he finished first, an hour ahead of his nearest rival, setting a course record. If exercise is medicine – as we are often told – surely the Spine Challenger is a massive overdose. To complete it takes more than 20 times the 10,000 steps that many of us aspire to each day. Yet hundreds of these ultramarathons have sprung up around the world, and the most prestigious have to turn eager contestants away. At the same time, lifts and escalators are jammed with people who would never consider climbing the stairs. In fact, the average person in the uS takes fewer than 5000 steps a day and in the uK, it isn’t much more. As a species, we have a love-hate relationship with exercise. Many people fail to get enough, some seem to get too much. So, what is the correct dose? Or, put another way for the Fitbit generation: how many daily steps should we take to make the most of this marvellous medicine? “Mostly we avoid exercise. Our lazy inner ape calls the shots far too often”. Dom and I met as PhD students in 2001, dissecting cadavers at Harvard Medical School. Chatting as we worked, we discovered a shared love of the mountains. A friendship was born amid the grease and formalin. In the years since, we have spent many happy days climbing, skiing and running together. The

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Curiositiesone constant has been Dom pulling ahead, wearing me out. So, I have a sense of how the other racers in the Spine Challenger must have felt. As a scientist working at the intersection of human evolution, energetics and health, I also find myself wondering what our species’ immense capacity for physical exertion tells us about the way our bodies are built. We evolved from lazy stock. All animals rest when they can, saving precious calories for survival and reproduction, but by any measure, our great ape relatives are impressively sedentary, resting and sleeping for 18 hours a day. However, when our ancestors began hunting and gathering, around 2.5 million years ago, it put an evolutionary premium on physical exertion. These activities are incredibly demanding, requiring hours of effort each day to find food. Individuals that were more active found more food and had more offspring – and these, in turn, inherited their desire to move. Over generations, the human brain evolved to reward hard work, releasing endorphins and endocannabinoids – the body’s homemade, feel-good drugs – in response to endurance exercise. The “runner’s high” was born, taking up residence in our brains alongside our ancient, simian desire to rest. These two competing drives were balanced by a lifestyle that demanded hard work, but rewarded strategic laziness. These sirens continue to call from opposite shores inside our evolved minds, luring us towards idleness or action. But recently, and in the blink of an evolutionary eye, our environment has changed. In the well-stocked human zoos, many of us now inhabit, we have largely engineered away hunger, fear and the other demons that got our hunter-gatherer ancestors moving. We have made it easy to overindulge, leading to heart disease, obesity, diabetes and other plagues of civilisation. In our Palaeolithic past, we could know what our bodies needed by listening to what they wanted. In the modern world, relying on our neural reward systems to deliver the proper dose of exercise feels a bit like trusting my 4-year-old daughter to serve herself healthy portions of broccoli and ice cream.

The perils of sloth

Our strange modern environment has also exposed our seemingly paradoxical relationship with exercise. Some of us, like Dom and other ultramarathon competitors, seek it out in large doses, feeding the evolved craving for physical activity. Yet, mostly we avoid it. Our lazy inner ape calls the shots far too often. The health benefits of exercise and the perils of sloth have long been known. Even Socrates, not remembered as an athlete, bemoaned the lack of fitness among his students. Today, many people would like to be more active to improve their health. But how much more? To get a better sense of the amount of exercise we should

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Curiositiesbe aiming for, we need to understand exactly what it does to our bodies. It has taken a surprisingly long time to figure that out, but recent work is illuminating. First, the obvious benefits: exercise keeps our muscles and hearts strong, our blood vessels pliant and improves aerobic fitness. When we get our heart rate up, the stresses imposed by the blood rushing through our arteries promotes the production of nitric oxide, which helps repair blood vessels and keep them elastic. Maintaining strength and aerobic fitness is particularly important as we age. Older adults who can cover at least 365 metres in a standard 6-minute walk test have half the risk of dying in the subsequent decade as their peers who can’t make 290 metres. Exercise does more than strengthen our hearts and muscles, though. It also has helpful suppressive effects all over the body. It reduces chronic inflammation, moderates levels of the reproductive hormones testosterone, oestrogen and progesterone, and blunts our physiological response to stress. This suppression has big health impacts. Chronic inflammation and stress are indiscriminate killers, increasing the risks for heart disease, cancer, diabetes, mental illness and other maladies. Research by David Raichlen at the university of Southern California, Gene Alexander at the university of Arizona and others is revealing how exercise keeps our brains fit too. Aerobic activity increases blood flow to the brain and causes the release of molecules that stimulate the generation of new brain cells and keep old ones healthy. Running, cycling and walking also challenge the brain to coordinate myriad signals involved in balance, navigation and movement, helping to maintain our cognitive reserve. Again, this is particularly important as we age because it helps ward off dementia and other forms of cognitive decline. “Being active doesn’t change the number of calories you spend each day; it changes how you spend them”

Counter-intuitively, one thing that exercise doesn’t do very well is increase our daily energy expenditure. Research from my lab, done with Raichlen and others, reveals that Hadza hunter-gatherers in Tanzania burn the same number of calories a day as adults in the uS and Europe, despite being five to 10 times as active. It isn’t that exercise is less energetically expensive for the Hadza (we checked). Instead, their bodies have adjusted to their physically active lifestyle by spending less energy on other tasks, which keeps their total daily calorie expenditure in check. The same seems to be true for people everywhere: being physically active doesn’t change the number of calories your body spends each day; it changes how you spend them.

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CuriositiesThis may be bad news for people relying on exercise to lose weight, but I believe it helps us understand why activity is so important in the modern world. I argue that this “metabolic management” underpins the suppressive effects of regular exercise. In our typically sedentary lives, the body has an abundance of calories at its disposal. As a result, physiological activities such as inflammation and the fight-or-flight response, which are normally short-lived and sporadic, are always on, raging in the background. Similarly, our reproductive systems produce an overabundance of sex hormones – twice the levels we see in populations like the Hadza. Exercise helps us regulate these and other overzealous activities. By forcing our bodies to economise, it helps prevent many of the diseases that haunt the developed world. As with all good things, there is a dark side to this. Taken too far, the suppressive effects of exercise can cut into essential functions. This might explain the curious finding, reported in many large studies, that extreme exercisers have slightly higher mortality rates than people who work out a couple of times a week. We also know that the rigorous regimes of elite athletes can lead to overtraining syndrome, a constellation of problems including reduced immunity and fertility. White blood cell counts crash. Colds last longer. libido drops. Women stop ovulating. Exercise stops being healthful and starts being harmful. So, how much exercise do we need to get to reap the crucial health benefits without feeling the downside? Because our body’s response to exercise evolved to meet the physical demands of hunting and gathering, perhaps populations who still forage for their food should be our guide? In communities like the Hadza, adults get about 2 hours a day of moderate-and-vigorous physical activity – meaning anything more strenuous than a casual stroll. Most of this comes in the form of hard walking: moving fast over hilly terrain, while scouring the landscape for food. There are plenty of other activities, though. Women often spend an hour or more digging starchy wild tubers from rocky ground. Men climb trees and chop into branches to expose bees’ nests and take honey. Kids drag firewood or haul buckets of water back to camp. Other indigenous communities have similar workloads. It is unlikely you would care to trade lifestyles with these hunter-gatherers. Their limited access to medicine means that children die far too often from curable, acute infections, skewing average life expectancy sharply downwards. But when it comes to the health conditions that those in the developed world are most likely to die from, hunter-gatherers are paragons of public health. Men and women in these communities regularly live into their 60s and 70s without any sign of the problems we often see as the inevitable consequences of ageing. They have the healthiest hearts on the planet, never develop diabetes, and stay strong and spry into old age. They are

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Curiositiesgetting the daily dose of exercise that humans evolved to require, and the health benefits are apparent. Even serious athletes might find it useful to gauge their exercise dosage by hunter-gatherer standards. My friend Dom aims for a very Hadza-like 2 hours of running per day to stay sharp for ultramarathons. Much more than that and he begins to sense the tell-tale signs of overtraining. Olympic-level athletes often log far longer training hours: swimmers might do 5 to 6 hours a day during intensive workouts. But it is telling that such workloads, and the arms race to pack in ever more training, can push some athletes towards the temptation of performance-enhancing drugs. Steroids and similar drugs mimic the hormones our bodies suppress when exercise cuts too deep. Athletes dope to ward off the effects of overtraining so they can push themselves past their evolved boundaries.

Post haste

For the rest of us, growing soft and sluggish in our hedonistic zoos, 2 hours’ exercise each day might seem like a lot. But people who manage it do get huge benefits. A study of postal workers in Glasgow, uK, found that those who clocked more than 15,000 steps a day carrying the mail, which equates to about 2 hours of brisk walking, had cardio-metabolic health on a par with hunter-gatherers – and this in a city with the lowest life expectancy in the country. A much larger study in the uS followed 4840 adults to see whether physical activity reduced the risk of dying over the subsequent five to eight years. No surprise, it found that more active people had lower mortality rates. Just 25 minutes of moderate-and-vigorous activity a day reduced the risk of dying within this timeframe by 25 per cent compared with the least active people. And more was better. Adults who were active for 100 minutes or more each day had the lowest mortality rates: 80 per cent lower than the couch potatoes. These and other similar studies suggest that current public health guidelines set the bar too low. In the uS, the Centres for Disease Control and Prevention recommends at least 25 minutes of moderate-and-vigorous exercise a day. (Some 90 per cent of people there fail to achieve this.) The 10,000-step target pursued by fitness-tracker enthusiasts – originally a marketing ploy dreamed up by a Japanese manufacturer of pedometers in 1965 – gives a comparable amount of exercise. This is because many of those steps won’t count as moderate-and-vigorous physical activity (see “How many steps?”). These targets are a good start – even low intensity steps at least get you moving – but we should strive for more. Benefits continue to accrue with more exercise, and the optimal dose seems to be closer to the levels we see with the Hadza. Higher exercise workloads may be particularly

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Curiositiesimportant for people who spend their days at a computer. A recent study of nearly 150,000 Australian adults found that it took over an hour a day of vigorous exercise to cancel out the ill-health effects of sitting during work hours. But if 15,000 steps a day/2 hours’ brisk walking is a distant goal for you, don’t be discouraged. A little of this medicine is still far better than none. Studies consistently show that even modest amounts of exercise confer huge health benefits compared with a slothful existence. For the most sedentary among us, an extra 30 minutes a day of activity that elevates our heart rate would halve our mortality rate, adding high quality healthy years to our lives. An evolutionary perspective suggests that most of us could do with more exercise. It is a powerful drug, but we shouldn’t be afraid to self-medicate liberally. The only dangerous dosages are “none” and “life isn’t fun anymore”. If you find a way to stay active that tickles your brain’s reward centres, you are doing it right. The best dose of exercise is the one that gets you coming back for more.

New Scientist, 12 June 2019

http://www.newscientist.com/

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Occupational Radiation Protection Aspects of Alkaline leach uranium in Situ Recovery (ISR) Facilities in the united States

Technical Notes

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Technical NotesBioaccessibility of nickel and cobalt in powders and massive forms of stainless steel, nickel- or cobalt-based alloys, and nickel and cobalt metals in artificial sweat

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