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Food Safety and Food Security 3/23/2013 BS-Microbiology Program, Semester -VI yasir Submitted By: Yasir Rehman (AH-411575) Muhammad Saqlian (AH-411610) Salauddin Khan (AH-411567)
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Page 1: Food safety & security full & final

Food Safety and Food Security 3/23/2013 BS-Microbiology Program, Semester -VI yasir

Submitted By: Yasir Rehman (AH-411575)

Muhammad Saqlian (AH-411610) Salauddin Khan (AH-411567)

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Food safety and food security Food safety and food security are interrelated concepts with a profound impact on quality of

human life, and there are many external factors that affect both of these areas.

Food safety:

Food safety is a scientific discipline describing handling, preparation, and storage of food in

ways that prevent foodborne illness. This includes a number of routines that should be

followed to avoid potentially severe health hazards.

The tracks within this line of thought are safety between industry and the market and then

between the market and the consumer. In considering industry to market practices, food

safety considerations include the origins of food including the practices relating to as follows:

Cleaning and sanitation

Pest control

Facilities & grounds

Air system/Ventilation

Water quality

Chemical control

Production equipment

Cross contamination prevention

Allergen control

Personal hygiene

Training

Supplier control

Specifications

Receiving, storage, shipping

Traceability/Recall

GMPs

In considering market to consumer practices, the usual thought is that food ought to be safe

in the market and the concern is safe delivery and preparation of the food for the consumer.

Why Need Food Safety: Food can transmit disease from person to person as well as serve as a growth medium for

bacteria that can cause food poisoning. In developed countries there are intricate standards

for food preparation, whereas in lesser developed countries the main issue is simply the

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availability of adequate safe water, which is usually a critical item. In theory, food poisoning

is 100% preventable. The five key principles of food hygiene, according to WHO, are:

Prevent contaminating food with pathogens spreading from people, pets, and pests.

Separate raw and cooked foods to prevent contaminating the cooked foods.

Cook foods for the appropriate length of time and at the appropriate temperature to

kill pathogens.

Store food at the proper temperature.

Do use safe water and cooked materials.

A priority of food chemical quality is control of allergens which can be life threatening to

some people that are highly sensitive. Other chemical properties of food such as vitamin and

mineral content are also important and affect the overall quality of the food but are not as

significant in terms of food safety. To prevent injury, the absence of foreign microphysical

particles is crucial. Microphysical particles such as glass and metal can be hazardous and

cause serious injury to consumers. Pathogenic bacteria, viruses and toxins produced by

microorganisms are all possible contaminants of food and impact food safety.

Interrelationship of food safety and food security

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Foreign objects in food products constitute the microphysical dangers. Foreign objects may

include bone or bone chips, metal flakes or fragments, injection needles, shotgun pellets,

pieces of product packaging, stones, glass or wood fragments, insects or other filth, personal

items, or any other foreign material not normally found in food products.

Many food animals can carry bacteria that are pathogenic to humans within their

gastrointestinal systems. For this reason, foods primarily of animal origin were thought to

cause a majority of foodborne illnesses. However, more foodborne illness outbreaks are

occurring due to contaminated fruits and vegetables.

Foods can become contaminated at any point along the production process. Thus, control

programs such as Hazard Analysis and Critical Control Points (HACCP) have been designed

and implemented in the industry to reduce food safety risks. Because the relative numbers

of illness are due to microorganisms rather than foreign objects or allergens, HAACP plans

typically focus on pathogen reduction and prevention. However, control of microorganisms,

allergens and foreign objects are considered individually rather than as a whole. Some

materials are considered unavoidable and thus tolerance levels have been set. For example,

in dates the allowable quantity of pit fragments is 2 pieces measuring 2 mm or longer

measured in the longest dimension per 900 grams of dates. However, due to the risk and

potential severity of disease certain hazards are not tolerated including contamination of

products by E. coli.

ISO 22000 ISO 22000 is a standard developed by the International Organization for Standardization

dealing with food safety. This is a general derivative of ISO 9000. ISO 22000 standard: The

ISO 22000 international standard specifies the requirements for a food safety management

system that involves interactive communication, system management, prerequisite

programs, HACCP (Hazards Analysis Critical Control Point) principles.

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HACCP: Hazard Analysis Critical Control Point (HACCP) is a preventive system of food control. It

involves examining and analyzing every stage of a food-related operation to identify and

assess hazards; determining the 'critical control points' at which action is required to control

the identified hazards; establishing the critical limits that must be met at, and procedures to

monitor, each critical control point; establishing corrective procedures when a deviation is

identified by monitoring; documentation of the HACCP plan and verification procedures to

establish that it is working correctly.

Food Safety Hazard

Any biological, chemical, or physical property that may cause a food to be unsafe for human

consumption Reasonably Likely To Occur - a hazard for which a prudent establishment would

establish controls because it historically has occurred, or because there is a reasonable

possibility that it will occur in the particular type of product being processed.

Seven Principles of Hazard Analysis and Critical Control Point (HACCP)

System In order to enhance food safety, every stage of the food production (from purchasing,

receiving, transportation, storage, preparation, handling, cooking to serving) should be

carried out and monitored scrupulously.

The HACCP system is a scientific and systematic approach to identify, assess and control of

hazards in the food production process. With the HACCP system, food safety control is

integrated into the design of the process rather than relied on end-product testing.

Therefore HACCP system provides a preventive and thus cost-effective approach in food

safety.

The seven principles of a HACCP System are-

1. Analyze hazards

2. Determine critical control points

3. Establish limits for critical control points

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4. Establish monitoring procedures for critical control points

5. Establish corrective actions

6. Establish verification procedures

7. Establish a record system

Principle 1 Analysis hazards A food safety hazard is any biological, chemical or physical property that may cause a food to

be unsafe for human consumption. We analyze hazards to identify any hazardous biological,

chemical, or physical property in raw materials and processing steps, and to assess their

likeliness of occurrence and potential to render food unsafe for consumption.

Principle 2 Determine critical control points A critical control point is a point, a step or a procedure in a food manufacture process at

which control can be applied and, as a result, a food safety hazard can be prevented,

eliminated, or reduced to an acceptable level.

Not every point identified with hazards and preventive measures will become a critical

control point. A logical decision-making process is applied to determine whether or not the

process is a critical control point. The logical decision-making process for determining critical

control points may include factors such as:

Whether control at this particular step is necessary for safety;

Whether control at this step eliminates or reduces the likely occurrence of the hazard

to an acceptable level;

Whether contamination with the hazard identified could occur in excess of

acceptable levels;

Whether subsequent steps will eliminate or acceptably reduce the hazard

Principle 3 Establish limits for critical control points Limit for critical control point is a criterion which separates acceptability from

unacceptability. It is the maximum or minimum value to which a physical, biological, or

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chemical hazard must be controlled at a critical control point to prevent, eliminate, or reduce

to an acceptable level the occurrence of the identified food safety hazard.

Examples of limits for critical control point are time, temperature, humidity, water activity

and pH value. The limits should be measurable.

In some cases, more than one critical limit is needed to control a particular hazard.

Principle 4 Establish monitoring procedures for critical control points Monitoring is a planned sequence of observations or measurements to assess whether a

critical control point is under control and to produce an accurate record for future use in

verification. Monitoring is very important for a HACCP system. Monitoring can warn the

plant if there is a trend towards loss of control so that it can take action to bring the process

back into control before the limit is exceeded.

The employee responsible for the monitoring procedure should be clearly identified and

adequately trained.

Principle 5 Establish corrective actions Corrective action is an action taken when the results of monitoring at the critical control

point indicate that the limit is exceeded, i.e. a loss of control.

Since HACCP is a preventive system to correct problems before they affect food safety, plant

management has to plan in advance to correct potential deviations from established critical

limits. Whenever a limit for critical control point is exceeded, the plant will need to take

corrective actions immediately.

The plant management has to determine the corrective action in advance. The employees

monitoring the critical control point should understand this process and be trained to

perform the appropriate corrective actions.

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Principle 6 Establish verification procedures Verification is the application of methods, procedures, tests and other evaluations, in

addition to monitoring, to determine compliance with the HACCP plan.

Some examples of verification are the calibration of process monitoring instruments at

specified intervals, direct observation of monitoring activities, and corrective actions.

Besides, sampling of product, monitoring records review and inspections can serve to verify

the HACCP system.

The plant management should check that the employees are keeping accurate and timely

HACCP records.

Principle 7 Establish a record system Maintaining proper HACCP records is an essential part of the HACCP system. Accurate and

complete HACCP records can be very helpful for:

Documentation of the establishment's compliance with its HACCP plan;

Tracing the history of an ingredient, in-process operations, or a finished product,

when problem arise;

Identifying trends in a particular operation that could result in a deviation if not

corrected;

Identifying and narrowing a product recall.

The record of a HACCP system should include records for critical control points,

establishments of limits, corrective actions, results of verification activities, and the HACCP

plan including hazard analysis.

To establish recordkeeping procedures, plant management may:

Develop forms to fully record corrective actions taken when deviations occur;

Identify employees responsible for entering monitoring data into the records and

ensure that they understand their roles and responsibilities

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Incidence A 2003 World Health Organization (WHO) report concluded that about 30% of According to

the WHO and CDC, in the USA alone, annually, there are 76 million cases of foodborne illness

leading to 325,000 hospitalizations and 5,000 deaths.

Some recent food safety examples having an impact on food security

1. Bangkok Post 26 Jan 2011

The sharp increase in pesticide use by Thai farmers has alarmed international markets.

Suggested by a researcher, DOA needs to impose complete ban on 4 hazardous chemicals

(carbofuran, dicrotophos, methomyl & EPN). •Thailand imported 42,089 tonnes of pesticides

in 1997 but the figure rose to 137,594 tonnes in 2009. •The EU recently found prohibited

chemicals inimported vegs (basil, chili, Chinese bitter cucumber & bean). Fears of a possible

EU ban on Thai vegs prompted govt to order a temporary suspension of shipments.

2. E.coli - Outbreak

Gaurdian 2 June 2011 :E coli outbreak: Russia widens EU vegetable ban ‐ Russia has extended

its ban on vegetable imports to all of the EU in a bid to prevent a deadly European bacterial

outbreak from spreading into the country.

Researchers are still unable to pinpoint the cause of the E coli outbreak that has hit Germany

and other European countries, infecting 1,500 people and leaving 17 people dead.

3. Dioxin

Dioxin contaminated Irish pork in 2008 exposed consumers to dioxin levels of 80‐200 times

above safety limits. Cause - pig feed from 1 producer tainted with industrial oil (used in 9

farms) – chain effect. Estimated losses > USD 1 billion.

4. Dioxin Feed Contamination - Germany: Swine & Poultry Farms 4 Jan 2011 ‐ In Northern Germany, about 1000 poultry & pig farms temporarily

quarantined due to an in‐feed dioxin scam. At least one, but possibly 9 feed m/f may be

involved. In the state of Lower Saxony alone, about 1000 farms (layer hens, broilers or pigs)

quarantined as a precautionary measure. Suppliers forced to suspend deliveries. The dioxin

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was found to have entered the food chain through eggs & poultry meat. • In another state,

North Rhine Westphalia, about 8000 layer hens had to be culled. The state's labs found

increased levels of dioxin ‐ in one case, levels were 4 times the allowed rate. • The dioxin

believed to have stemmed from feed contaminated with industrial fats. These fats possibly

substituted for vegetable fats during feed manufacturing.

5. Melamine Contamination of Infant Formula:

Melamine added in the primary production sector (milk collection centers) to disguise

diluting milk with water • 22 of 79 Chinese powdered infant formula producers affected

Products from affected producers exported to 5 countries . Levels detected range from <0.1 -

2600 mg/kg.

Other products affected: Milk powder), yoghurt, biscuits, instant & liquid coffee, egg

powder, fresh eggs, animal feed Exports reported all over the world.

Outcome – Melamine Infant Formula:

294 000 children ill, 50 000 hospitalized, 6 deaths occurred. Company officials charged with

criminal offences, 2 executed.

Regulatory agencies World Health Organization (WHO) and Food and Agriculture Organization (FAO): In 2003, the

WHO and FAO published the Codex Aliment Arius which serves as a guideline to food safety.

Food Safety and Pakistan

Pakistan does not have an integrated legal framework but has a set of laws, which deals with

various aspects of food safety. These laws, despite the fact that they were enacted long time

ago, have tremendous capacity to achieve at least minimum level of food safety. However,

like many other laws, these laws remain very poorly enforced. There are four laws that

specifically deal with food safety. Three of these laws directly focus issues related to food

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safety, while the fourth, the Pakistan Standards and Quality Control Authority Act, is

indirectly relevant to food safety.

The Pure Food Ordinance 1960 consolidates and amends the law in relation to the

preparation and the sale of foods. All provinces and some northern areas have adopted this

law with certain amendments. Its aim is to ensure purity of food being supplied to people in

the market and, therefore, provides for preventing adulteration. The Pure Food Ordinance

1960 does not apply to cantonment areas. There is a separate law for cantonments called

"The Cantonment Pure Food Act, 1966". There is no substantial difference between the Pure

Food Ordinance 1960 and The Cantonment Pure Food Act. Even the rules of operation are

very much similar.

Pakistan Hotels and Restaurant Act, 1976 applies to all hotels and restaurants in Pakistan and

seeks to control and regulate the rates and standard of service(s) by hotels and restaurants.

In addition to other provisions, under section 22(2), the sale of food or beverages that are

contaminated, not prepared hygienically or served in utensils that are not hygienic or clean is

an offense. There are no express provisions for consumer complaints in the Pakistan

Restaurants Act, 1976, Pakistan Penal Code, 1860 and Pakistan Standards and Quality

Control Authority Act, 1996. The laws do not prevent citizens from lodging complaints with

the concerned government officials; however, the consideration and handling of complaints

is a matter of discretion of the officials.

Food Security

Food security has been defined by the Food and Agriculture Organization (FAO) of the United

Nations (UN) as; "Food security exists when all people, at all times, have physical, social and

economic access to sufficient, safe and nutritious food which meets their dietary needs and

food preferences for an active and healthy life. Household food security is the application of

this concept to the family level, with individuals within households as the focus of concern"

(FAO 2003).

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T

The FAO estimated that a total of 925 million people were undernourished in 2010, less than

during the food and economic crisis of 2008–2009, but still unacceptably high (FAO, 2010).*

Figure given below is based on the latest data available to FAO, dotted lines indicate

estimates for 2009 and 2010 by FAO, and the United States Department of Agriculture (FAO

2010). Most of the undernourished people in the world live in developing countries, 2/3 of

them in just seven countries (Bangladesh, China, the Congo, Ethiopia, India, Indonesia and

Pakistan) and over 40 percent live in China and India alone. Sub-Saharan Africa has the

highest proportion of undernourished with 30% of the population being in this category.

Food security is affected by climate change, dependence on fossil fuels, the loss of

biodiversity and use of food crops for biofuels, among many other factors

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*Figure: Number of people, worldwide who lack food security 1969-2010 (FAO 2011).

Climate Change and Food Security The term climate change has been used in recent years to refer specifically to climate change

caused by human activity (anthropomorphic climate change), and is often used

interchangeably with the term global warming. Many studies have examined the effects of

climate change on crop yield. Gregory et al. (1999) determined that yields of wheat and rice

decreased about 5% per degree rise above 32°C. Model simulations of maize production in

Africa and Latin America predicted an overall reduction of 10% by 2055 (Jones & Thornton

2003). Stability of the food supply may be affected by an increase in the frequency or

severity of such extreme events as cyclones, floods, hailstorms or droughts

(Intergovernmental Panel on Climate Change 2007). However, food security relies not only

on availability of food but also on ability of the household to prepare and store food and on

the families' access to the available food. The ability of people to use food effectively will

also be impacted by climate change by increasing the possibility for water and food borne

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diseases. Researchers have found that common food borne illnesses such as salmonellosis

show a nearly linear increase in reported cases for each degree of increase in weekly

temperature (D'Souza et al., 2004; Fleury et al. 2006; Kovats et al. 2004). Access to food

refers to the ability to obtain sufficient quantity and quality of food, whether through

purchasing or production. Effects of climate change on food access therefore depend on

income, food prices and productivity.

Global warming: causes and effects

Fossil Fuel Dependence and Food Security Industrialized farming grew exponentially in developed countries after World War Two, and

the Green Revolution of the 1950s and 1960s introduced the concept to many developing.

Food production worldwide increased and grain harvest increased by 250%. Fossil fuels in

agriculture are used to produce fertilizers and pesticides and to fuel farm machinery and

irrigation systems. Skebrowski (2004) estimated that 95% of all food products require oil use

in their production or processing. According to researchers at the University of Michigan's

Center for Sustainable Agriculture, it takes an average 7 calories of fossil fuel to produce,

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process and ship each calorie of energy in food (Heller & Keoleian 2000). Fossil fuels are

becoming increasingly constrained which will have an impact on food security, especially in

countries that rely heavily of food imports.

Loss of Biodiversity The term "biodiversity" is a combination of the words biological and diversity, and is used to

refer to the variety of life on earth. The Green Revolution encouraged the development of

"high yield" varieties in both plant and animal crops by use of interbreeding between animals

or plants with desired characteristics. The FAO estimates that almost 75% of diverse

agricultural crops have been lost over the last century, and fears that hundreds of the 7000

animal breeds registered in its databases are threatened by extinction (FAO 2008). According

to FAO, only twelve crops and fourteen animal crop species are the basis for most of the

food in the world. As biodiversity declines, the food supply becomes more vulnerable to

climate change and water scarcity. Over the past few years there has been an increasing

awareness of the importance of protecting biodiversity for food crops, and gene banks have

been instituted. Gene banks are used to preserve genetic material, both plant and animal.

Plants may be preserved by freezing cuts from the plant, or stocking the seeds. Animal genes

can be conserved by the freezing of sperm or eggs in zoological freezers until further need.

Coral fragments may be preserved by storage in water tanks under controlled conditions.

Currently there are now some 1,750 gene banks worldwide, and in 2008 the Svalbald Global

Seed Vault was opened in Norway as the definitive back-up for crop diversity (FAO 2010).

Stunting and chronic nutritional deficiencies

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Children with symptoms of low calorie and protein intake and a nurse attendant at a Nigerian orphanage in the late 1960s.

Many countries experience perpetual food shortages and distribution problems. These result

in chronic and often widespread hunger amongst significant numbers of people. Human

populations respond to chronic hunger and malnutrition by decreasing body size, known in

medical terms as stunting or stunted growth. This process starts in utero if the mother is

malnourished and continues through approximately the third year of life. It leads to higher

infant and child mortality, but at rates far lower than during famines. Once stunting has

occurred, improved nutritional intake later in life cannot reverse the damage. Stunting itself

is viewed as a coping mechanism, designed to bring body size into alignment with the

calories available during adulthood in the location where the child is born. Limiting body size

as a way of adapting to low levels of energy (calories) adversely affects health in three ways:

Premature failure of vital organs occurs during adulthood. For example, a 50-year-old

individual might die of heart failure because his/her heart suffered structural defects

during early development;

Stunted individuals suffer a far higher rate of disease and illness than those who have

not undergone stunting;

Severe malnutrition in early childhood often leads to defects in cognitive

development.

Rather than one level of survival, there are numerous levels at which a population and a food

supply can be in equilibrium in the sense that they can be indefinitely sustained. However,

some levels will have smaller people and higher normal mortality than others.

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Agricultural diseases (e.g. wheat stem rust)

Stripe rust on a wheat stem

Diseases affecting livestock or crops can have devastating effects on food availability

especially if there are no contigency plans in place. For example, an epidemic of stem rust on

wheat caused by race Ug99 which was spreading across Africa and into Asia in 2007 caused

major concern. A virulent wheat disease could destroy most of the world’s main wheat

crops, leaving millions to starve. The fungus had spread from Africa to Iran and may already

be in Pakistan.

The genetic diversity of the crop wild relatives of wheat can be used to improve modern

varieties to be more resistant to rust. In their centers of origin wild wheat plants are

screened for resistance to rust, then their genetic information is analysed and finally wild

plants and modern varieties are crossed through means of modern plant breeding in order

to transfer the resistance genes from the wild plants to the modern varieties.

Biofuels and Food Security Biofuels are a wide range of fuels which are in some way derived from biomass, material

from recently living organisms such as grains, wood or waste. The term first generation

biofuels refers to those fuels made from agricultural crops such as corn, cane or soy. Corn is

the main source of ethanol for biofuels produced in the U.S., and many critics feel that using

a food crop such as corn contributes to the increasing number of hungry in the world by

driving grain prices higher (Walsh 2008). Second generation biofuels are made from waste

biomass, such as the stalks of wheat, corn, wood, or special biomass crops. Development of

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biofuels has been promoted as a way to ease the effects of climate change, lessen concerns

about fossil fuel usage and stimulate rural development. The OPEC Fund for International

Development commissioned a study on Biofuels and Food Security (IIASA 2009). This study

indicates that the development of first generation biofuels results in small increases of

agricultural value but does not increase food security because of risks of deforestation and

loss of biodiversity, and net greenhouse gas savings will be seen only after 2030. The study

also found that second generation biofuels, if produced on land other than cultivated land

required to produce food, might produce environmentally friendly and economically sound

biofuels dependent upon development of technologies capable of converting cellulose to

biofuels as well as land use regulations.

How Can You Keep Food Safe During a Power Failure? Keep the freezer door closed to keep cold air inside. Don’t open the door any more than

necessary. A full freezer will stay at safe temperatures about 2 days; a half-full freezer about

1 day. If your freezer is not full,

group packages so they form an “igloo” to protect each other. If you think the power will be

out for several days, try to find some dry ice. Keep dry ice wrapped and do not touch it with

your bare hands. Use cubed ice or block ice in the refrigerator. Even if food has started to

thaw, foods can be safely kept in the freezer. The foods in your freezer that partially or

completely thaw before power is restored may be safely refrozen if they still

contain ice crystals or are 40 °F or below. You will have to evaluate each item separately.

When indoubt, throw it out.

How Long Should Canned Foods Be Kept? Store canned foods and other shelf-stable products in a cool, dry place.

Never put them above the stove, under the sink, in a damp garage or basement, or any place

exposed to high or low temperature extremes.

Store high-acid foods, such as tomatoes and other fruit, up to 18 months. Low-acid foods,

such as meat and vegetables, can be kept 2 to 5 years. While extremely rare, a toxin

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produced by Clostridium botulinum is the worst danger in canned foods. NEVER USE food

from containers that show signs of “botulism”: leaking, bulging, rusting, or badly dented

cans; cracked jars; jars with loose or bulging lids; canned food with a foul odor; or any

container that spurts liquid when opening.DO NOT TASTE THIS FOOD! Even the tiniest

amount of botulinum toxin can be deadly.

Summary The challenge of food security is to assure that all people have access to enough food to lead

productive lives, but a large part of food security is assuring the food is safe from a chemical,

physical or biological aspect. There are numerous other aspects of food security. We have

discussed a few of the more prominent, including the effects of climate change on crop

production, the effect of fossil fuel dependence on the import and export of food, the loss of

many lines of plant and animal food stock, as well as the impact of the use of food crops to

produce biofuels.

References:

http://en.wikipedia.org/wiki/Food_safety http://www.nature.com/scitable/knowledge/library/food-safety-and-food-security-

68168348 www.crcp.org.pk/doc.../Food%20Safety%20Legislation%20in%20Pa Siraj, Mazhar (2004). "Food Safety Legislation in Pakistan" (DOC). Consumer Rights

Commission of Pakistan. Gregory, P. J. et al. Managed production systems. In: Walker B, Steffen W, Canadell J,

Ingram J.S.I, editors. The terrestrial biosphere and global change: implications for natural and managed systems. Cambridge University Press; Cambridge, UK (1999)

Kovats, R. S. et al. The effect of temperature on food poisoning: a time-series analysis of salmonellosis in ten European countries. Epidemiology and Infection 132, 443-453 (2004)

Skrebowski, S. Joining the dots. Presentation to Energy Institute Conference, London, 10 November 2004.

Fleury, M. et al. A time series analysis of the relationship of ambient temperature and common bacterial enteric infections in two Canadian provinces International Journal of Biometeorology 50, 385-391 (2006)

FAO. The state of food insecurity in the world (2010).

Munir Ahmad. The State of Food Security in Pakistan .PIDE, (2010)