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    Academy of Brains & Career Subhashree Biotech

    PROJECT ONPROJECT ON

    r

    SOURCES AT SODEPUR, KOLKATA

    The Degree of Bachelor of Science in Applied Biotechnology

    Under

    The Sikkim Manipal University of Health, Medical & Technological

    Sciences

    Project is submitted by

    Name: ANUP KUMAR OJHAName: ANUP KUMAR OJHA

    Registration Number: 520687137Registration Number: 520687137

    Semester: BSc. BT-6thSemester: BSc. BT-6th

    Study Centre

    ABC FOUNDATIONStudy Center Code 1831

    BB 36, Sector 1, Salt Lake City

    Kolkata 700064West Bengal

    [email protected] 1

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    This is to certify that this project is done under my guidance byAnup Kumar Ojha, a student of Sikkim Manipal University of

    Health, Medical and Technological Science, Roll No. 520687137Bachelor of Science in Applied Biotechnology.

    The Project Report has not been submitted for any other examination and

    does not form a part of other course undergone by the candidate.

    Internal Examiner External Examiner

    Academy of Brains & Career Subhashree Biotech

    [email protected] 2

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    I hereby declare that project report titled

    Qualitative Analysis and Determination of MPN Index of various water sample

    collected from different sources at Sodepur, Kolkata

    Submitted to the

    SIKKIM MANIPAL UNIVERSITY OF HEALTH, MEDICAL &TECHNOLOGICAL

    SCIENCES

    in partial fulfillment of the requirement of the degree of

    Bachelor of Science in Applied Biotechnology

    It is my original work and not submitted for the award of any other degree, diploma, or

    other similar title or prizes.

    Signature

    Kolkata

    Dated: Registration No. 520687137

    11/27/2011

    [email protected] 3

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    Submitted by:

    ANUP KUMAR OJHAVI B.Sc. Biotechnology

    Roll No. 520687137

    Subject code: BO0033

    Centre code: 01831

    Sikkim Manipal University

    Supervisor:

    Dr. I. P. PoddarChairman

    Subhasree Biotech

    A Unit of the Calcutta Silk Mfg. Co. Ltd.

    23, B. T. Road

    KOLKATA-700115

    Project report submitted for the partial fulfillment of the requirement for qualifying

    B.Sc. Biotechnology from Sikkim Manipal University

    Contents

    [email protected] 4

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    SL. NO. TOPIC PAGE NO.

    1. Certification of work ---

    2. Student deceleration ---

    3. Acknowledgement ---

    4. Introduction

    Water quality & Contaminants

    Sources of drinking water in the Earth

    Coliform Index

    Indicator organism

    Quality of potable water

    08 - 12

    5. Aim & Objective 13

    6. Materials & Method

    Materials

    Methods

    1. Preparation of culture media2. Test for water potability and

    determination of MPN Index

    3. Gram Staining4. MPN Index

    13-18

    7. Observation & Result 18 - 22

    8. Discussion 23

    9. Reference 23 - 24

    Acknowledgement

    [email protected] 5

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    The work embodied in the project has been carried out for partial fulfillment of the

    requirement for the completion of B.Sc. Biotechnology from Sikkim Manipal University.

    The project has been entitled as Qualitative Analysis and Determination of MPN

    Index of Various Water Samples Collected from Different Sources at Sodepur,

    Kolkata.

    I would like to convey my thanks and regards to Dr. I. P. Poddar, Director of Subhasree

    Biotech. It is, indeed, for him I learnt a lot during the tenure of my training period.

    My special thanks go to Dr. S. Sukul and Dr. P. Datta for providing me this opportunity

    to work in this highly esteemed laboratory and also for the valued suggestions given from

    time to time which, I believe, will go a long way with me to build an enshrining future

    ahead.

    It is my extreme pleasure and great opportunity to express my profound sense of gratitude

    to Mr. Tanmoy Sarkar and Mr. Soummya Seal, Project Associate, Subhasree Biotech for

    their guidance, constant encouragement, affection and great help in the completion andpresentation of this project work.

    I also express sincere gratitude to Mr. Sidhartha Banerjee, Mr. Anirban Roy Chowdhury

    and Mr. Sumit Kumar Dey for their constant inspiration as well as warm and valuable

    suggestions which helped me a lot to complete this project work.

    I also tender my owe to the Director cum Principal Mr. S.K.D Burman, Faculty in-charge

    Mrs. Sanjogita Basu and other respected faculties of ABC Foundation for granting my

    long cherished dream to work amidst expertise and state-of-the-art laboratory.

    Last but not the least; I thank my parents for their all round support extended at the time

    of need.

    (ANUP KUMAR OJHA)

    VI B.Sc. Biotechnology

    Registration No: 520687137

    Learning Centre Code: 01831ABC Foundation

    Sikkim Manipal University

    [email protected] 6

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    [email protected] 7

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    1. INTRODUCTION

    Water of sufficient quality to be used as drinking water is termed Potable Water.

    Although many fresh watersources are utilized by humans, some contain diseasevectorsorpathogens and cause long-term health problems if they do not meet certain water

    quality guidelines. Water that is not harmful for human beings is sometimes called safe

    waterthat is not contaminated to the extent of being unhealthy. The available supply ofdrinking water is an important criterion for the population supported by the planet Earth.

    As of the year 2006 (and pre-existing for at least three decades), there is a substantial

    shortfall in availability of potable water, primarily arising from overpopulation in lesser

    developed countries. As of the year 2000, 37% of the populations of lesser developedcountries did not have access to safe drinking water [1]. Implications for disease

    propagation are significant. The World Health Organization (WHO) sets international

    standards for drinking water.

    Typically water supply networks deliver a single quality of water, whether it is to be usedfor drinking, washing or landscape irrigation; one example is urban China, where

    drinking water can be optionally delivered by a separate tap. In the United States, public

    drinking water is governed by the Safe Drinking Water Act (SDWA) that protects theright of employees to report potential violations.

    The standard test forbacterial contamination is a laboratory analysis ofcoliform bacteria,

    a convenient marker for a class of harmful fecalpathogens. The presence of fecal

    coliforms (likeEscherichia coli) serves as an indication of contamination by sewage.

    Over large parts of the world, humans drink water that contains disease vectors orpathogens or contain unacceptable levels of dissolved contaminants or solids in

    suspension. Such waters are not potable water and drinking such waters or using them in

    cooking leads to widespread acute, chronic illness and sometimes even death.

    1.1. Water quality and contaminants

    Throughout most of the world the most common contamination of raw water sources is

    from human sewage and in particular human faecal pathogens and parasites. In 2006,

    waterborne diseases were estimated to cause 1.8 million deaths each year while about 1.1

    billion people lacked proper drinking water.

    [1]

    . It is clear that people in the developingworld need to have access to good quality water in sufficient quantity, water purification

    technology and availability and distribution systems for water. In many parts of the world

    the only sources of water are from small streams often directly contaminated by sewage.Even wells do not eliminate the risk of contamination.

    Most water requires some type of treatment before use. The extent of treatment depends

    on the source of the water.

    [email protected] 8

    http://en.wikipedia.org/wiki/Fresh_waterhttp://en.wikipedia.org/wiki/Diseasehttp://en.wikipedia.org/wiki/Vector_(biology)http://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Water_qualityhttp://en.wikipedia.org/wiki/Water_qualityhttp://en.wikipedia.org/wiki/Water_qualityhttp://en.wikipedia.org/wiki/Safe_waterhttp://en.wikipedia.org/wiki/Safe_waterhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Overpopulationhttp://en.wikipedia.org/wiki/Lesser_developed_countrieshttp://en.wikipedia.org/wiki/Lesser_developed_countrieshttp://en.wikipedia.org/wiki/Drinking_water#_note-0http://en.wikipedia.org/wiki/Drinking_water#_note-0http://en.wikipedia.org/wiki/Diseasehttp://en.wikipedia.org/wiki/World_Health_Organizationhttp://en.wikipedia.org/wiki/Water_supply_networkhttp://en.wikipedia.org/wiki/Landscapehttp://en.wikipedia.org/wiki/Landscapehttp://en.wikipedia.org/wiki/Irrigationhttp://en.wikipedia.org/wiki/Chinahttp://en.wikipedia.org/wiki/United_Stateshttp://en.wikipedia.org/wiki/Safe_Drinking_Water_Acthttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Coliformhttp://en.wikipedia.org/wiki/Coliformhttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Fecal_coliformshttp://en.wikipedia.org/wiki/Fecal_coliformshttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Sewagehttp://en.wikipedia.org/wiki/Diseasehttp://en.wikipedia.org/wiki/Vector_(biology)http://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Waterborne_diseaseshttp://en.wikipedia.org/wiki/Drinking_water#cite_note-0http://en.wikipedia.org/wiki/Water_purificationhttp://en.wikipedia.org/wiki/Diseasehttp://en.wikipedia.org/wiki/Vector_(biology)http://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Water_qualityhttp://en.wikipedia.org/wiki/Water_qualityhttp://en.wikipedia.org/wiki/Safe_waterhttp://en.wikipedia.org/wiki/Safe_waterhttp://en.wikipedia.org/wiki/Earthhttp://en.wikipedia.org/wiki/Overpopulationhttp://en.wikipedia.org/wiki/Lesser_developed_countrieshttp://en.wikipedia.org/wiki/Lesser_developed_countrieshttp://en.wikipedia.org/wiki/Drinking_water#_note-0http://en.wikipedia.org/wiki/Diseasehttp://en.wikipedia.org/wiki/World_Health_Organizationhttp://en.wikipedia.org/wiki/Water_supply_networkhttp://en.wikipedia.org/wiki/Landscapehttp://en.wikipedia.org/wiki/Irrigationhttp://en.wikipedia.org/wiki/Chinahttp://en.wikipedia.org/wiki/United_Stateshttp://en.wikipedia.org/wiki/Safe_Drinking_Water_Acthttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Coliformhttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Fecal_coliformshttp://en.wikipedia.org/wiki/Fecal_coliformshttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Sewagehttp://en.wikipedia.org/wiki/Diseasehttp://en.wikipedia.org/wiki/Vector_(biology)http://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Waterborne_diseaseshttp://en.wikipedia.org/wiki/Drinking_water#cite_note-0http://en.wikipedia.org/wiki/Water_purificationhttp://en.wikipedia.org/wiki/Fresh_water
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    The most reliable way to kill microbial pathogenic agents is to heat water to a boiling [3],

    but this requires abundant sources of fuel and is very onerous on the households

    especially where it is difficult to store boiled water in sterile conditions. Othertechniques, such as varying forms of filtration, chemical disinfection, and exposure to

    ultraviolet radiation (including solar UV) have been demonstrated in an array of

    randomized control trials to significantly reduce levels of water-borne disease amongusers in low-income countries.

    Parameters for drinking water quality typically fall under two categories: chemical/

    physical and microbiological. Chemical/ Physical parameters include heavy metals, trace

    organic compounds, Total Suspended Solids (TSS) and turbidity. Microbiologicalparameters include Coliform bacteria,E. coli, and specific pathogenic species ofbacteria

    (such as cholera-causing Vibrio cholerae),viruses, andprotozoanparasites.

    Chemical parameters tend to pose more of a chronic health risk through build-up of

    heavy metals although some components like nitrates/ nitrites and arsenic may have a

    more immediate impact. Physical parameters affect the aesthetics and taste of thedrinking water and may complicate the removal of microbial pathogens.

    Originally, fecal contamination was determined with the presence of coliform bacteria, a

    convenient marker for a class of harmful fecalpathogens. The presence of faecalcoliforms (like E. coli) serves as an indication of contamination by sewage. Additional

    contaminants include protozoanoocysts such as Cryptosporidiumsp., Giardia lamblia,Legionella, and viruses (enteric) [5]. Microbial pathogenic parameters are typically ofgreatest concern because of their immediate health risk.

    1.2. Sources of drinking water in the Earth

    Earth's surface consists of 70% water. But sources where drinkable water may be

    obtained include:

    Ground sources such as groundwater,hydrosphere zones and aquifers

    Precipitation which includes rain, hail, snow, fog, etc.

    Surface watersuch as rivers, streams, glaciers

    Biological sources such as plants

    The sea through de-salination

    As of the year 2000, 27% of the populations of lesser developed countries did not have

    access to safe drinking water

    [6]

    . This proportion has declined steadily over the lastdecades. Implications fordisease propagation are significant.

    The lack of water and the lack of hygiene is one of the biggest problems that many poorcountries have encountered. The problem has reached such endemic proportions that 2.2

    million deaths per annum occur from unsanitary water 90% of these are children under

    the age of five[4]. Solar water disinfection is a low-cost method of purifying water thatcan often be implemented with locally available materials.

    [email protected] 9

    http://en.wikipedia.org/wiki/Drinking_water#cite_note-2http://en.wikipedia.org/wiki/Heavy_metalshttp://en.wikipedia.org/wiki/Heavy_metalshttp://en.wikipedia.org/wiki/Organic_compoundshttp://en.wikipedia.org/wiki/Total_suspended_solidshttp://en.wikipedia.org/wiki/Turbidityhttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/E._colihttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Cholerahttp://en.wikipedia.org/wiki/Vibrio_choleraehttp://en.wikipedia.org/wiki/Viruseshttp://en.wikipedia.org/wiki/Viruseshttp://en.wikipedia.org/wiki/Protozoanhttp://en.wikipedia.org/wiki/Parasiteshttp://en.wikipedia.org/wiki/Arsenichttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Fecal_coliformshttp://en.wikipedia.org/wiki/Fecal_coliformshttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Sewagehttp://en.wikipedia.org/wiki/Protozoanhttp://en.wikipedia.org/wiki/Protozoanhttp://en.wikipedia.org/wiki/Oocystshttp://en.wikipedia.org/wiki/Cryptosporidiumhttp://en.wikipedia.org/wiki/Cryptosporidiumhttp://en.wikipedia.org/wiki/Giardia_lambliahttp://en.wikipedia.org/wiki/Legionellahttp://en.wikipedia.org/wiki/Viruseshttp://en.wikipedia.org/wiki/Drinking_water#cite_note-4http://en.wikipedia.org/wiki/Drinking_water#cite_note-4http://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Groundwaterhttp://en.wikipedia.org/wiki/Hyporheic_zonehttp://en.wikipedia.org/wiki/Aquiferhttp://en.wikipedia.org/wiki/Precipitation_(meteorology)http://en.wikipedia.org/wiki/Surface_waterhttp://en.wikipedia.org/wiki/Glacierhttp://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Seahttp://en.wikipedia.org/wiki/De-salinationhttp://en.wikipedia.org/wiki/Drinking_water#cite_note-5http://en.wikipedia.org/wiki/Diseasehttp://www.ethoswater.com/index.cfm?objectid=6406649E-F1F6-6035-B59D53E360F38354http://www.ethoswater.com/index.cfm?objectid=6406649E-F1F6-6035-B59D53E360F38354http://en.wikipedia.org/wiki/Solar_water_disinfectionhttp://en.wikipedia.org/wiki/Drinking_water#cite_note-2http://en.wikipedia.org/wiki/Heavy_metalshttp://en.wikipedia.org/wiki/Organic_compoundshttp://en.wikipedia.org/wiki/Total_suspended_solidshttp://en.wikipedia.org/wiki/Turbidityhttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/E._colihttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Cholerahttp://en.wikipedia.org/wiki/Vibrio_choleraehttp://en.wikipedia.org/wiki/Viruseshttp://en.wikipedia.org/wiki/Protozoanhttp://en.wikipedia.org/wiki/Parasiteshttp://en.wikipedia.org/wiki/Arsenichttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Fecal_coliformshttp://en.wikipedia.org/wiki/Fecal_coliformshttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Sewagehttp://en.wikipedia.org/wiki/Protozoanhttp://en.wikipedia.org/wiki/Oocystshttp://en.wikipedia.org/wiki/Cryptosporidiumhttp://en.wikipedia.org/wiki/Giardia_lambliahttp://en.wikipedia.org/wiki/Legionellahttp://en.wikipedia.org/wiki/Viruseshttp://en.wikipedia.org/wiki/Drinking_water#cite_note-4http://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Groundwaterhttp://en.wikipedia.org/wiki/Hyporheic_zonehttp://en.wikipedia.org/wiki/Aquiferhttp://en.wikipedia.org/wiki/Precipitation_(meteorology)http://en.wikipedia.org/wiki/Surface_waterhttp://en.wikipedia.org/wiki/Glacierhttp://en.wikipedia.org/wiki/Biologyhttp://en.wikipedia.org/wiki/Seahttp://en.wikipedia.org/wiki/De-salinationhttp://en.wikipedia.org/wiki/Drinking_water#cite_note-5http://en.wikipedia.org/wiki/Diseasehttp://www.ethoswater.com/index.cfm?objectid=6406649E-F1F6-6035-B59D53E360F38354http://en.wikipedia.org/wiki/Solar_water_disinfection
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    1.3. Coliform Index

    The Coliform Index is a rating of the purity ofwaterbased on a count of fecalbacteria.

    Coliform bacteria are microorganisms that primarily originate in the intestines ofwarm-blooded animals. By testing for coliforms, especially the well knownE.Coli, which is a

    thermo-tolerant coliform, one can determine if the water has probably been exposed tofecal contamination; that is, whether it has come in contact with human or animal feces.It is important to know this because many disease-causing organisms are transferred from

    human and animal feces to water, from where they can be ingested by people and infect

    them. Water that has been contaminated by feces usually contains pathogenic bacteria,which can cause disease. Some types of coliforms cause disease, but the coliform index is

    primarily used to judge if other types of pathogenic bacteria are likely to be present in the

    water.

    The Coliform Index is used because it is difficult to test for pathogenic bacteria directly.There are many different types of disease-causing bacteria, and they are usually present

    in low numbers which do not always show up in tests. Thermo-tolerant coliforms arepresent in higher numbers than individual types of pathogenic bacteria and they can betested for relatively easily.

    However, the Coliform Index is far from perfect. Thermo-tolerant coliforms can survive

    in water on their own, especially in tropical regions, so they do not always indicate fecal

    contamination. Furthermore, they do not give a good indication of how many pathogenicbacteria are present in the water, and they give no idea at all of whether there are

    pathogenic viruses orprotozoa which also cause diseases and are rarely tested for.

    Therefore, it does not always give accurate or useful results regarding the purity of water.

    1.4. Indicator organism

    Indicator organisms are used to measure potential fecal contamination of environmentalsamples. The presence ofcoliform bacteria, such asE. coli, in surface wateris a common

    indicator offecal contamination. Coliform bacteria in water samples may be quantified

    using the most probable number (MPN) method, a probabilistic test which assumescultivable bacteria meet certain growth and biochemical criteria. If preliminary tests

    suggest that coliform bacteria are present at numbers in excess of an established cut-off

    (the Coliform Index), fecal contamination is suspected and confirmatory assays such asthe Eijckman test are conducted.

    Coliform bacteria selected as indicators of fecal contamination must not persist in theenvironment for long periods of time following efflux from the intestine, and their

    presence must be closely correlated with contamination by other fecal organisms.Indicator organisms need not be pathogenic .

    Non-coliform bacteria, such asStreptococcus bovis and Clostridia may also be used as an

    index of fecal contamination .

    [email protected] 10

    http://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/Microorganismhttp://en.wikipedia.org/wiki/Warm-bloodedhttp://en.wikipedia.org/wiki/Warm-bloodedhttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Virushttp://en.wikipedia.org/wiki/Protozoanhttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/E._colihttp://en.wikipedia.org/wiki/Surface_waterhttp://en.wikipedia.org/wiki/Water_quality#Measurementhttp://en.wikipedia.org/wiki/Coliform_Indexhttp://en.wikipedia.org/w/index.php?title=Eijckman_test&action=edit&redlink=1http://en.wikipedia.org/wiki/Streptococcus_bovishttp://en.wikipedia.org/wiki/Streptococcus_bovishttp://en.wikipedia.org/wiki/Clostridiahttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Feceshttp://en.wikipedia.org/wiki/Bacteriahttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/Microorganismhttp://en.wikipedia.org/wiki/Warm-bloodedhttp://en.wikipedia.org/wiki/Warm-bloodedhttp://en.wikipedia.org/wiki/Escherichia_colihttp://en.wikipedia.org/wiki/Pathogenhttp://en.wikipedia.org/wiki/Virushttp://en.wikipedia.org/wiki/Protozoanhttp://en.wikipedia.org/wiki/Coliform_bacteriahttp://en.wikipedia.org/wiki/E._colihttp://en.wikipedia.org/wiki/Surface_waterhttp://en.wikipedia.org/wiki/Water_quality#Measurementhttp://en.wikipedia.org/wiki/Coliform_Indexhttp://en.wikipedia.org/w/index.php?title=Eijckman_test&action=edit&redlink=1http://en.wikipedia.org/wiki/Streptococcus_bovishttp://en.wikipedia.org/wiki/Clostridia
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    1.5. Quality of potable water

    Water quality is the physical, chemical and biological characteristics ofwater. It is most

    frequently used by reference to a set of standards against which compliance can beassessed. The most common standards used to assess water quality relate to drinking

    water, safety of human contact, and for health ofecosystems.

    1.5.1. Standards

    In the setting of standards, agencies make political and technical/scientific decisions

    about how the water will be used . In the case of natural water bodies, they also makesome reasonable estimate of pristine conditions. Different uses raise different concerns

    and therefore different standards are considered. Natural water bodies will vary in

    response to environmental conditions. Environmental scientists work to understand howthese systems function which in turn helps to identify the sources and fates of

    contaminants.

    The vast majority ofsurface wateron the planet is neitherpotable nortoxic. This remains

    true even if sea water in the oceans (which is too salty to drink) is not counted. Anothergeneral perception of water quality is that of a simple property that tells whether water is

    polluted or not. In fact, water quality is a very complex subject, in part because water is a

    complex medium intrinsically tied to the ecology of the Earth. Industrial pollution is amajor cause of water pollution, as well as runoff from agricultural areas, urban storm

    water runoff and discharge of treated and untreated sewage (especially in developing

    countries).

    1.5.2. Parameters for measurement

    The complexity of water quality as a subject is reflected in the many types ofmeasurements of water quality indicators. Some of the simple measurements are

    Temperature

    pH

    Dissolved Oxygen

    Conductivity

    Oxygen Reduction Potential (ORP)

    More complex measurements that must be made in a lab setting require a water sample to

    be collected, preserved, and analyzed at another location.

    [email protected] 11

    http://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Drinking_waterhttp://en.wikipedia.org/wiki/Drinking_waterhttp://en.wikipedia.org/wiki/Ecosystemhttp://en.wikipedia.org/w/index.php?title=Environmental_scientists&action=edit&redlink=1http://en.wikipedia.org/wiki/Surface_waterhttp://en.wikipedia.org/wiki/Potablehttp://en.wikipedia.org/wiki/Toxicityhttp://en.wikipedia.org/wiki/Pollutionhttp://en.wikipedia.org/wiki/Ecologyhttp://en.wikipedia.org/wiki/Water_pollutionhttp://en.wikipedia.org/wiki/Stormwater_runoffhttp://en.wikipedia.org/wiki/Stormwater_runoffhttp://en.wikipedia.org/wiki/Sewagehttp://en.wikipedia.org/wiki/Developing_countrieshttp://en.wikipedia.org/wiki/Developing_countrieshttp://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/wiki/Dissolved_oxygenhttp://en.wikipedia.org/wiki/Conductivityhttp://en.wikipedia.org/wiki/Reduction_potentialhttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Drinking_waterhttp://en.wikipedia.org/wiki/Drinking_waterhttp://en.wikipedia.org/wiki/Ecosystemhttp://en.wikipedia.org/w/index.php?title=Environmental_scientists&action=edit&redlink=1http://en.wikipedia.org/wiki/Surface_waterhttp://en.wikipedia.org/wiki/Potablehttp://en.wikipedia.org/wiki/Toxicityhttp://en.wikipedia.org/wiki/Pollutionhttp://en.wikipedia.org/wiki/Ecologyhttp://en.wikipedia.org/wiki/Water_pollutionhttp://en.wikipedia.org/wiki/Stormwater_runoffhttp://en.wikipedia.org/wiki/Stormwater_runoffhttp://en.wikipedia.org/wiki/Sewagehttp://en.wikipedia.org/wiki/Developing_countrieshttp://en.wikipedia.org/wiki/Developing_countrieshttp://en.wikipedia.org/wiki/PHhttp://en.wikipedia.org/wiki/Dissolved_oxygenhttp://en.wikipedia.org/wiki/Conductivityhttp://en.wikipedia.org/wiki/Reduction_potential
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    The following is a list of indicators often measured by situational category:

    Physical assessment

    Alkalinity

    Color of water PH

    Taste and odor (geosmin, 2-methylisoborneol (MIB), etc)

    Dissolved metals and salts (sodium, chloride, potassium, calcium, manganese,magnesium)

    Microorganisms such as fecal coliform bacteria ( Escherichia coli),

    Cryptosporidium, and Giardia lamblia

    Dissolved metals and metalloids (lead, mercury, arsenic, etc.) Dissolved organics: colored dissolved organic matter(CDOM), dissolved organic

    carbon (DOC)

    Radon

    Heavy metals Pharmaceuticals

    Hormone analogs

    Temperature

    Total suspended solids (TSS)

    Turbidity

    Chemical assessment

    PH

    Conductivity (also see salinity)

    Dissolved Oxygen (DO)

    Nitrate-N

    O rthophosphates

    Chemical oxygen demand (COD)

    Biochemical oxygen demand (BOD)

    Pesticides

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    http://en.wikipedia.org/wiki/Alkalinityhttp://en.wikipedia.org/wiki/Color_of_waterhttp://en.wikipedia.org/wiki/Geosminhttp://en.wikipedia.org/wiki/Sodiumhttp://en.wikipedia.org/wiki/Chloridehttp://en.wikipedia.org/wiki/Potassiumhttp://en.wikipedia.org/wiki/Calciumhttp://en.wikipedia.org/wiki/Manganesehttp://en.wikipedia.org/wiki/Magnesiumhttp://en.wikipedia.org/wiki/Fecal_coliform_bacteriahttp://en.wikipedia.org/wiki/Cryptosporidiumhttp://en.wikipedia.org/wiki/Giardia_lambliahttp://en.wikipedia.org/wiki/Leadhttp://en.wikipedia.org/wiki/Mercury_(element)http://en.wikipedia.org/wiki/Arsenichttp://en.wikipedia.org/wiki/Colored_dissolved_organic_matterhttp://en.wikipedia.org/wiki/Dissolved_organic_carbonhttp://en.wikipedia.org/wiki/Dissolved_organic_carbonhttp://en.wikipedia.org/wiki/Radonhttp://en.wikipedia.org/wiki/Heavy_metalshttp://en.wikipedia.org/wiki/Pharmaceuticalhttp://en.wikipedia.org/wiki/Hormonehttp://en.wikipedia.org/wiki/Temperaturehttp://en.wikipedia.org/wiki/Total_suspended_solidshttp://en.wikipedia.org/wiki/Turbidityhttp://en.wikipedia.org/wiki/Electrical_conductivityhttp://en.wikipedia.org/wiki/Salinityhttp://en.wikipedia.org/wiki/Dissolved_Oxygenhttp://en.wikipedia.org/wiki/Nitratehttp://en.wikipedia.org/wiki/Orthophosphatehttp://en.wikipedia.org/wiki/Chemical_oxygen_demandhttp://en.wikipedia.org/wiki/Biochemical_oxygen_demandhttp://en.wikipedia.org/wiki/Pesticidehttp://en.wikipedia.org/wiki/Alkalinityhttp://en.wikipedia.org/wiki/Color_of_waterhttp://en.wikipedia.org/wiki/Geosminhttp://en.wikipedia.org/wiki/Sodiumhttp://en.wikipedia.org/wiki/Chloridehttp://en.wikipedia.org/wiki/Potassiumhttp://en.wikipedia.org/wiki/Calciumhttp://en.wikipedia.org/wiki/Manganesehttp://en.wikipedia.org/wiki/Magnesiumhttp://en.wikipedia.org/wiki/Fecal_coliform_bacteriahttp://en.wikipedia.org/wiki/Cryptosporidiumhttp://en.wikipedia.org/wiki/Giardia_lambliahttp://en.wikipedia.org/wiki/Leadhttp://en.wikipedia.org/wiki/Mercury_(element)http://en.wikipedia.org/wiki/Arsenichttp://en.wikipedia.org/wiki/Colored_dissolved_organic_matterhttp://en.wikipedia.org/wiki/Dissolved_organic_carbonhttp://en.wikipedia.org/wiki/Dissolved_organic_carbonhttp://en.wikipedia.org/wiki/Radonhttp://en.wikipedia.org/wiki/Heavy_metalshttp://en.wikipedia.org/wiki/Pharmaceuticalhttp://en.wikipedia.org/wiki/Hormonehttp://en.wikipedia.org/wiki/Temperaturehttp://en.wikipedia.org/wiki/Total_suspended_solidshttp://en.wikipedia.org/wiki/Turbidityhttp://en.wikipedia.org/wiki/Electrical_conductivityhttp://en.wikipedia.org/wiki/Salinityhttp://en.wikipedia.org/wiki/Dissolved_Oxygenhttp://en.wikipedia.org/wiki/Nitratehttp://en.wikipedia.org/wiki/Orthophosphatehttp://en.wikipedia.org/wiki/Chemical_oxygen_demandhttp://en.wikipedia.org/wiki/Biochemical_oxygen_demandhttp://en.wikipedia.org/wiki/Pesticide
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    2. Aim & Objective

    To survey water quality of various samples collected from different sources at Sodepur,

    Kolkata, West Bengal.

    3. Materials & Method

    3.1. Materials

    3.1.1. Water sample

    Water sample was collected from various sources:

    Municipal water

    Canal water Pond water

    Ganga river water

    Rain water

    Drain water

    3.1.2. Culture media preparation

    Lactose (SRL), Tryptone (SRL), Yeast Extract (SRL), Bromothymol blue (SRL),

    Distilled water, Endo agar (Hi-Media), Eosin Methylene blue agar (Hi-Media)

    3.1.3. Glass & Plastic wares

    Conical flask (BOROSIL & RIVIERA), Petri-plates (RIVIERA & POLY-LAB), Beaker

    (RIVIERA), Test tube (RIVIERA), Pipette (RIVIERA & POLY-LAB), Measuring

    Cylinder (POLYLAB & RIVIERA), Durhams Tube, 1000l, 100l and 10l tips

    (TARSON), Micro-tip box (TARSON)

    3.1.4. Instruments

    Autoclave (LAMBDA), Incubator (LAMBDA ORIONIS), Laminar Air Flow (LAMBDA

    ORIONIS), pH Meter (EI), Hot Air Oven (LAMBDA), Balance (DHONA), 4C Freezer

    (GODREJ), Micropipette (Hi-Media)

    3.1.5. Others

    Non-absorbent cotton, Absorbent cotton, Tissue Paper, Marker, Test tube rack, Papers,

    Rubber band, Spatula, Spirit lamp, Alcohol, Inoculation Loop, Butter Paper, MPN Chart

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    3.2. Methods

    3.2.1. Preparation of culture media

    Composition of media:

    1. Double Strength Lactose Broth

    Lactose- 10g

    Tryptone- 10g

    Yeast Extract - 5g

    Bromothymol Blue- 2ml

    Distilled Water- 1000ml

    pH- 7.0

    2. Single Strength Lactose Broth

    Lactose- 5g

    Tryptone- 10g

    Yeast Extract - 5g

    Bromothymol Blue- 2ml

    Distilled Water- 1000ml

    pH- 7.0

    3. Endo Agar

    Peptone- 10g

    Lactose- 10g

    K2HPO4- 3.5g

    Na2SO3- 2.5g

    Basic Fuschin- 0.5g

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    Agar- 20g

    Distilled Water- 1000ml

    pH- 7.0

    4. Eosin Methylene Blue Agar (EMB)

    Peptone- 10g

    Sucrose- 5g

    Lactose- 5g

    K2HPO4- 2g

    Agar- 2g

    Eosin- 4ml

    Methylene Blue- 0.06mg

    Distilled Water- 1000ml

    pH- 7.0

    These components were weighed and dissolved in 1000ml of distilled water. After pH set

    up, they were autoclaved at 121C for 15 minutes at 15lb/inch2

    pressure prior to itsplating on sterile petridishes.

    3.2.2. Test for water potability and determination of MPN index

    A coliform is facultative and aerobic that ferments lactose to produce gas and is Gram

    negative, non-sporing rod which can be identified by three different tests.

    (a) Presumptive test

    (b) Confirmed test

    (c) Completed test

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    The Presumptive test

    In this test, a series of 9 test tubes of lactose broth are inoculated with measured amount

    of water to see if the water contains any lactose fermenting bacteria that produce gas. Ifafter incubation gas is seen in any of the lactose broth, it is presumed that coliforms are

    present in the water sample. This test is also to determine the Most Probable Number(MPN) of coliform per 100ml of water.

    Confirmed test

    In this, test plates of EMB Agar or Endo Agar is inoculated from positive gas tubes. Thismedia inhibits the growth of Gram positive bacteria and helps in distinguishing coliform

    colonies from non-coliforms. On EMB Agar coliforms produce colonies that give green

    metallic sheen, while on the Endo Agar they produce pink nucleated colony.

    Completed test

    This test is to determine whether the isolated form from the agar plate is a coliform or

    not. The organism is inoculated into a lactose broth and onto a nutrient agar slant. If gas

    is produced in the lactose tube and a slide from the slant shows the presence of Gram

    negative, Non-sporing rod; then it is confirmed that coliform is present.

    Coliform present may beE. coli orEnterobacter aerogens; of the twoE. coli is the better

    sewage indicator sinceE. aerogens can be of non-sewage origin. To differentiate between

    these two species IMViC tests are performed.

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    3.2.3. Gram Staining

    A slide is de-greased and a loopful of culture is smeared on it

    Air dry, add Crystal Violet and retain for 60 sec. Wash

    Add Grams iodine, keep for 60 sec.

    Rinse with Grams decolorizer (95% Ethanol)

    Add Safranin and keep for 30-60 sec. Wash

    Air dry and observe under 10X, 45X and 100X respectively

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    3.2.4. MPN index

    Number of tubes giving positive reaction

    out of

    MPN index

    per 100ml

    95% confidence limits

    3 of 10ml

    each

    3 of 1ml

    each

    3 of 0.1ml

    each

    Lower Upper

    0 0 1 3

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    Hence, from visualizing the changed color of the media and trapped gas it is assumed that

    the sample may be contaminated with sewage.

    Sample-1: Municipal Water

    Color of the media in all tubes remained blue and no gas bubble was seen in theDurhams tube.

    Sample-2: Canal Water

    Color of the media in all tubes changed from blue to yellow and gas bubble was seen in

    the Durhams tube.

    Sample-3: Pond Water

    Color of the media in all tubes changed from blue to yellow and gas bubble was seen in

    the Durhams tube.

    Sample-4: Ganga River Water

    Color of the media in 2 DSLB tubes and 1 SSLB tube (containing 1ml of the sample)

    changed from blue to yellow and the remaining test tubes retained the blue color of the

    media. Gas bubble was seen in the Durhams tubes of those tubes in which color of themedia changed from blue to yellow.

    Sample-5: Rain Water

    Color of the media in 2 DSLB tubes, 2 SSLB tubes (containing 1ml of the sample) and 1

    SSLB tube (containing 0.1ml of the sample) changed from blue to yellow and theremaining test tubes retained the blue color of the media. Gas bubble was seen in the

    Durhams tubes of those tubes in which color of the media changed from blue to yellow.

    Sample-6: Drain Water

    Color of the media in all tubes changed from blue to yellow and gas bubble was seen in

    the Durhams tube.

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    The over all observations are summed here in the following table:

    Sample

    No. of tubes showing positive result

    MPN

    index per

    100ml

    Lower

    limit

    Upper

    limitDSLB

    (10ml)

    SSLB

    (1ml)

    SSLB

    (0.1ml)

    Municipal

    Water

    1 0 0

    4

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    Figure 1: DSLB and SSLB possess Bromothymol blue as an internal indicator that

    changes its color as pH of the medium declines from alkaline to acidic range; also

    Durhams tube is inserted to trap gas bubbles produced, if any. In the negative tube [Fig-1(a)], lactose was not fermented to acid and gas, hence color of the media remained blue

    (the color of the indicator in an alkaline solution) and no gas was trapped in the Durhams

    tube. On the contrary, in the positive tube [Fig- 1(b)], lactose was fermented to acid(there by changing the color of the medium to yellow from blue) and gas (trapped in the

    Durhams tube).

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    Figure 2: Determination of MPN requires samples to be inoculated in 3 DSLB tubes

    containing 10ml sample each, 3 SSLB tubes containing 1ml sample each and 3 SSLBtubes containing 0.1ml sample each. Fig-2 shows two complete set ups. Fig-1(a) shows

    negative result as color of the medium remained blue and no gas bubbles were produced,

    while Fig-1(b) shows a positive result as color of the medium changed from blue toyellowish with decline in pH and gas bubbles were trapped in the Durhams tubes.

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    5. Discussion

    During the course of studying water quality of various samples by determining MPNindex, we got a mixed result.

    Municipal water sample has a very low MPN index (4) and hence is not contaminatedwith sewage. Therefore its potability is unquestionable.

    Ganga water has an MPN index of 15. This indicates that Ganga water is sewage polluted. But since the load is very less, the water can be decontaminated by

    commercially available water purification process to convert it into human consumable

    water.

    Rain water has an MPN index of 28. This can be used as a potential substitute to potable

    water. Natural water bodies are bearing the brunt of high pollution level. Also ground

    water level is declining. In this juncture if rain water can be stored and decontaminated, it

    can meet the massive demand to supply safe potable water.

    Canal water, pond water and drain water in the surveyed locality have the highest MPNindex (1100) and hence they are highly contaminated with sewage and therefore not fit to

    drink at all.

    6. References

    1. U.S. Centers for Disease Control and Prevention. Atlanta, GA (March 2006).Safe Water System: A Low-Cost Technology for Safe Drinking Water. Fact

    Sheet, World Water Forum 4 Update.

    2. Centre for Affordable Water and Sanitation Technology (March 2008),Household Water Treatment Guide,

    3. WHOs Guidelines for Drinking Water Quality

    4. Clasen, T., Schmidt, W., Rabie, T., Roberts, I., Cairncross, S (Published 12 March

    2007). Interventions to improve water quality for preventing diarrhea: asystematic review and meta-analysis. British Medical Journal,

    doi:10.1136/bmj.39118.489931.BE

    5. U.S. EPA. Drinking Water Contaminants: Microorganisms.6. I.A. Shiklomanov (2000), Appraisal and Assessment of World Water Resources,

    Water International 25(1): 11-32

    7. Conroy R.M., Meegan M.E., Joyce T., McGuigan K., Barnes J. (1999), solardisinfection of water reduces diarrhoeal disease, an update, Arch Dis Child, Vol.

    81.

    [email protected] 23

    http://www.cdc.gov/safewater/publications_pages/fact_sheets/WW4.pdfhttp://webmail.cawst.org/documents/Camille/New%20Training%20Materials/HWT%20Manual_Mar%2008.pdfhttp://epa.gov/safewater/contaminants/index.html#listmclhttp://www.cdc.gov/safewater/publications_pages/fact_sheets/WW4.pdfhttp://webmail.cawst.org/documents/Camille/New%20Training%20Materials/HWT%20Manual_Mar%2008.pdfhttp://epa.gov/safewater/contaminants/index.html#listmcl
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    8. Conroy R.M., Meegan M.E., Joyce T.M., McGuigan K.G., Barnes J. (2001) Use

    of solar disinfection protects children under 6 years from cholera. Arch Dis Child;

    85:293-2959. Rose A. at al. (2006). Solar disinfection of water for diarrhoeal prevention in

    Southern India. Arch Dis Child, 91(2): 139-141

    10. Hobbins M. (2003). The SODIS Health Impact Study, Ph.D. Thesis, SwissTropical Institute Basel

    11. United Nations Childrens Fund (UNICEF, Sep, 2006). New York, NY. Safe

    Drinking Water. Excerpt from Progress since the World Summit for Children:A Statistical Review.

    12. March 2008, Cashing in on Climate Change, IBIS World

    13. United States Environmental Protection Agency (EPA, 2006). Washington, DC.

    Water Quality Standards Review and Revision.14. Oblinger, J. L. and J. A. Koburger, J. A. (1975). Understanding and Teaching the

    Most Probable Number Technique. J. Milk Food Technol. 38(9), 540-545.

    ________________

    THANK YOU

    http://www.unicef.org/specialsession/about/sgreport-pdf/03_SafeDrinkingWater_D7341Insert_English.pdfhttp://www.unicef.org/specialsession/about/sgreport-pdf/03_SafeDrinkingWater_D7341Insert_English.pdfhttp://www.unicef.org/specialsession/about/sgreport-pdf/sgreport_adapted_stats_eng.pdfhttp://www.unicef.org/specialsession/about/sgreport-pdf/sgreport_adapted_stats_eng.pdfhttp://www.ibisworld.com/pressrelease/pressrelease.aspx?prid=125:http://www.epa.gov/waterscience/standards/about/rev.htmhttp://www.unicef.org/specialsession/about/sgreport-pdf/03_SafeDrinkingWater_D7341Insert_English.pdfhttp://www.unicef.org/specialsession/about/sgreport-pdf/03_SafeDrinkingWater_D7341Insert_English.pdfhttp://www.unicef.org/specialsession/about/sgreport-pdf/sgreport_adapted_stats_eng.pdfhttp://www.unicef.org/specialsession/about/sgreport-pdf/sgreport_adapted_stats_eng.pdfhttp://www.ibisworld.com/pressrelease/pressrelease.aspx?prid=125:http://www.epa.gov/waterscience/standards/about/rev.htm