Infection and transmission
Thus, an improvement would be increasing the capacity of laboratories to identify specific pathogens and developing mechanisms to facilitate reporting of specific diseases. Br Dent J ; Some of the amino acids are convertible with the expenditure of energy to glucose and can be used for energy production, just as ordinary glucose, in a process known as gluconeogenesis. Some wording error on the previous one when i was trying to explain about age classification. Many studies have examined the potential of diets and dietary components as a first-line intervention in the prevention and treatment of metabolic syndrome [ 4 ]. The methodological quality of the trials was generally unclear because of insufficient data included in the reports.
Good research. Valid results. Better decisions.
Symptoms of beriberi include weight loss, emotional disturbances, impaired sensory perception , weakness and pain in the limbs, and periods of irregular heart rate.
Edema swelling of bodily tissues is common. It may increase the amount of lactic acid and pyruvic acid within the blood. In advanced cases, the disease may cause high-output cardiac failure and death. Symptoms may occur concurrently with those of Wernicke's encephalopathy , a primarily neurological thiamine-deficiency related condition.
Beriberi is divided into four categories as follows. The first three are historical and the fourth, gastrointestinal beriberi, was recognized in Dry beriberi causes wasting and partial paralysis resulting from damaged peripheral nerves. It is also referred to as endemic neuritis. It is characterized by:. A selective impairment of the large proprioceptive sensory fibers without motor impairment can occur and present as a prominent sensory ataxia , which is a loss of balance and coordination due to loss of the proprioceptive inputs from the periphery and loss of position sense.
Wernicke's encephalopathy WE , Korsakoff's syndrome alcohol amnestic disorder , Wernicke—Korsakoff syndrome are forms of dry beriberi. Korsakoff's syndrome is, in general, considered to occur with deterioration of brain function in patients initially diagnosed with WE. Following improved nutrition and the removal of alcohol consumption, some impairments linked with thiamine deficiency are reversed, in particular poor brain functionality, although in more severe cases, Wernicke—Korsakoff syndrome leaves permanent damage.
Wet beriberi affects the heart and circulatory system. It is sometimes fatal, as it causes a combination of heart failure and weakening of the capillary walls, which causes the peripheral tissues to become edematous. Wet beriberi is characterized by:. Infantile beriberi usually occurs between two and six months of age in children whose mothers have inadequate thiamine intake.
It may present as either wet or dry beriberi. In the acute form, the baby develops dyspnea and cyanosis and soon dies of heart failure. These symptoms may be described in infantile beriberi:. Beriberi may also be caused by shortcomings other than inadequate intake: All these causes mainly affect the central nervous system, and provoke the development of what is known as Wernicke's disease or Wernicke's encephalopathy.
Wernicke's disease is one of the most prevalent neurological or neuropsychiatric diseases. In alcohol abusers , autopsy series showed neurological damages at rates of In addition, uncounted numbers of people can experience fetal damage and subsequent diseases. Genetic diseases of thiamine transport are rare but serious. Thiamine responsive megaloblastic anemia TRMA with diabetes mellitus and sensorineural deafness  is an autosomal recessive disorder caused by mutations in the gene SLC19A2 ,  a high affinity thiamine transporter.
TRMA patients do not show signs of systemic thiamine deficiency, suggesting redundancy in the thiamine transport system. This has led to the discovery of a second high-affinity thiamine transporter, SLC19A3. Pathological similarities between Leigh disease and WE led to the hypothesis that the cause was a defect in thiamine metabolism.
One of the most consistent findings has been an abnormality of the activation of the pyruvate dehydrogenase complex. Mutations in the SLC19A3 gene have been linked to biotin-thiamine responsive basal ganglia disease  which is treated with pharmacological doses of thiamine and biotin , another B vitamin. Other disorders in which a putative role for thiamine has been implicated include subacute necrotising encephalomyelopathy , opsoclonic cerebellopathy a paraneoplastic syndrome , and Nigerian seasonal ataxia.
In addition, several inherited disorders of ThDP-dependent enzymes have been reported,  which may respond to thiamine treatment.
Thiamine in the human body has a half-life of 18 days and is quickly exhausted, particularly when metabolic demands exceed intake. A derivative of thiamine, thiamine pyrophosphate TPP , is a cofactor involved in the citric acid cycle , as well as connecting the breakdown of sugars with the citric acid cycle. The citric acid cycle is a central metabolic pathway involved in the regulation of carbohydrate, lipid, and amino acid metabolism, and its disruption due to thiamine deficiency inhibits the production of many molecules including the neurotransmitters glutamic acid and GABA.
A positive diagnosis test for thiamine deficiency can be ascertained by measuring the activity of the enzyme transketolase in erythrocytes Erythrocyte Transketolase Activation Assay.
Thiamine, as well as its phosphate derivatives, can also be detected directly in whole blood, tissues, foods, animal feed, and pharmaceutical preparations following the conversion of thiamine to fluorescent thiochrome derivatives Thiochrome Assay and separation by high-performance liquid chromatography HPLC. Many people with beriberi can be treated with thiamine alone. In situations where concentrated thiamine supplements are unavailable, feeding the person with a thiamine-rich diet e.
Following thiamine treatment, rapid improvement occurs, in general, within 24 hours. Historically, beriberi was associated with a diet including much polished rice white rice ; when the relationship between polishing rice and the disease was discovered, it became possible to prevent and treat the deficiency condition, for example with inexpensive rice bran.
Beriberi caused by inadequate nutritional intake is rare today in developed countries [ citation needed ] because of quality of food and the fact that many foods are fortified with vitamins. Beriberi is a recurrent nutritional disease in detention houses, even in this century. In , an outbreak of beriberi occurred in a detention center in Taiwan.
Before beginning treatment, prisoners exhibited symptoms of dry or wet beriberi with neurological signs tingling: Populations under extreme stress may be at higher risk for beriberi. Displaced populations , such as refugees from war, are susceptible to micronutritional deficiency, including beriberi.
Sun Simiao — CE was the first person in medical history to document the diagnosis, treatment, and prevention of beriberi leg edema due to vitamin B1 deficiency , a deficiency disease caused by lack of vitamin B1.
For this, he prescribed combinations of herbs rich in vitamin B1 and unpolished rice the outer layer of rice and other grains rich in B vitamins. In the late 19th century, beriberi was studied by Takaki Kanehiro , a British-trained Japanese medical doctor of the Japanese Navy.
The voyage lasted more than nine months and resulted in cases of sickness and 25 deaths on a ship of men. With the support of the Japanese Navy, he conducted an experiment in which another ship was deployed on the same route, except that its crew was fed a diet of meat, fish, barley, rice, and beans. At the end of the voyage, this crew had only 14 cases of beriberi and no deaths. This convinced Takaki and the Japanese Navy that diet was the cause.
In , Christiaan Eijkman , a Dutch physician and pathologist , demonstrated that beriberi is caused by poor diet, and discovered that feeding unpolished rice instead of the polished variety to chickens helped to prevent beriberi. The following year, Sir Frederick Hopkins postulated that some foods contained "accessory factors"—in addition to proteins, carbohydrates, fats, and salt—that were necessary for the functions of the human body.
According to the Oxford English Dictionary , the term "beriberi" comes from a Sinhalese phrase meaning "weak, weak" or "I cannot, I cannot", the word being duplicated for emphasis. According to Jacobus Bontius Jacob de Bondt; — , a Dutch physician who encountered the disease while working in Java in , In the first known description of beriberi or, beri-beri , he wrote: I believe those, whom this same disease attacks, with their knees shaking and the legs raised up, walk like sheep.
It is a kind of paralysis, or rather tremor: As most feedstuffs used in poultry diets contain enough quantities of vitamins to meet the requirements in this species, deficiencies in this vitamin do not occur with commercial diets. This was, at least, the opinion in the s. Mature chickens show signs 3 weeks after being fed a deficient diet.
In young chicks, it can appear before 2 weeks of age. Onset is sudden in young chicks. There is anorexia and an unsteady gait. Later on, there are locomotor signs, beginning with an apparent paralysis of the flexor of the toes. The characteristic position is called "stargazing", meaning a chick "sitting on its hocks and the head in opisthotonos ".
Response to administration of the vitamin is rather quick, occurring a few hours later. Differential diagnosis include riboflavin deficiency and avian encephalomyelitis. In riboflavin deficiency, the "curled toes" is a characteristic symptom. Muscle tremor is typical of avian encephalomyelitis. A therapeutic diagnosis can be tried by supplementing thiamine only in the affected bird. If the animals do not respond in a few hours, thiamine deficiency can be excluded. Polioencephalomalacia PEM is the most common thiamine deficiency disorder in young ruminant and nonruminant animals.
Symptoms of PEM include a profuse, but transient, diarrhea, listlessness, circling movements, star gazing or opisthotonus head drawn back over neck , and muscle tremors. These bacteria produce thiaminases that will cause an acute thiamine deficiency in the affected animal. Snakes that consume a diet largely composed of goldfish and feeder minnows are susceptible to developing thiamine deficiency. This is often a problem observed in captivity when keeping garter and ribbon snakes that are fed a goldfish-exclusive diet, as these fish contain thiaminase, an enzyme that breaks down thiamine.
Thiamine deficiency has been identified as the cause of a paralytic disease affecting wild birds in the Baltic Sea area dating back to It affects primarily 0. They shaped an important part of landscapes worldwide and are home to many of the world's richest wildlife. Farming also supports a diverse rural community that is not only a fundamental asset of international culture, but also plays an essential role in maintaining the environment in a healthy state.
Farming is an activity whose significance goes beyond simple food production. Throughout the production chain processes occur that can have an impact on the natural environment and consequently, directly or indirectly, on human health and development.
For example, heavy use of pesticides and fertilizers, incorrect drainage or irrigation practices, a high level of mechanization or unsuitable land use can produce environmental degradation. However, abandonment of farming activities can also endanger the environmental heritage through loss of semi-natural habitats as well as biodiversity and landscape associated with them.
Likewise, the effect of agricultural production systems on human health directly farmer's occupational health or indirectly consumer's health through food are increasingly being recognized as an integrated element in the broader evaluation of environmental risks related to agriculture.
The links between the richness of the natural environment and farming practices are complex. While many valuable habitats are maintained by extensive farming, and a wide range of wild species rely on this for their survival, agricultural loss of wildlife can be the result of inappropriate agricultural practices and land use.
Discussions on possible future environmental effects of new technologies in food production will necessarily have to take outset in the present situation of agricultural effects on the environment, including derived effects on human health, recognizing that present trends of conventional agriculture are likely to be reflected in the objectives of modern food production. Agriculture adds to greenhouse gas GHG problems. There are three main sources of GHG emissions from agriculture: N2O nitrous oxide emissions from soils, mainly due to nitrogen fertilization; CH4 methane emissions from intestinal fermentation, CH4 and N2O emissions from manure management.
Measures being considered include: Further development of renewable, agricultural biomass could contribute to reductions in emissions from energy and transport, while benefiting the agricultural sector. Water pollution by nitrates from agricultural sources, where improved agricultural practices are thought to improve pollution. Pesticides have been proven to have an effect on the environment and ecosystems by reducing biodiversity, especially by reducing weeds and insects which are often important elements of the food chain e.
In addition, human health can be negatively affected through direct exposure and indirect exposure, e. Systems to reduce the need for pesticide use, especially integrated pest management, organic farming or in some cases genetically modified crops are increasingly investigated at national and international level . Soil degradation processes such as desertification, erosion, decline in soil organic matter, soil contamination e.
Such degradation processes can result from inappropriate farming practices such as unbalanced fertilization, over abstraction of groundwater for irrigation, improper use of pesticides, use of heavy machinery, or overgrazing.
Measures to prevent soil degradation include support to organic farming, conservation tillage, the protection and maintenance of terraces, safer pesticide use, integrated crop management, management of low-intensity pasture systems, lowering stock density and the use of certified compost.
Irrigation can also lead to environmental concerns, such as over-extraction of water from subterranean aquifers, irrigation driven erosion, soil salinization, alteration of pre-existing semi-natural habitats and, secondary impacts arising from the intensification of the agricultural production permitted by irrigation. In recent decades, the rate of decline and even disappearance of species and related habitats, ecosystems and genes i. Declines in biodiversity are of direct consequence for food security when they affect food related organisms and relatives with relevance for breeding.
Furthermore, intensified agriculture including modern breeding systems has resulted in significant reductions of landraces, adapted to local specificities as well as traditional knowledge.
Assessment of agricultural impacts on the environment requires the use of holistic models which are able to integrate multiple sources of information . Previous scientific discussions have concluded that solutions applied at farm level contributed environmental problems but they are not adequate to the task of realizing long-term environmental goals.
This requires system innovations at higher levels of aggregation, involving, for example, looking for opportunities to negotiate recycling systems by linking sectors within agriculture and other areas affecting the environment, e.
As a consequence of public discussion, new concepts for policies of agriculture and environment interactions have been developed in many countries including an improved public monitoring and responsibility for sustainability. Secretary-General Kofi Annan in June , is an international work programme designed to meet the needs of decision makers and the public for scientific information concerning the consequences of ecosystem change for human well-being and options for responding to those changes.
The MA focuses on ecosystem services the benefits people obtain from ecosystems , how changes in ecosystem services have affected human well-being, how ecosystem changes may affect people in future decades, and response options that might be adopted at local, national, or global scales to improve ecosystem management and thereby contribute to human well-being and poverty alleviation. Work on agro-environmental indicators provided information on the current state and changes in the conditions of the environment in agriculture.
It also resulted in a better understanding of linkages between the causes and impacts of agriculture on the environment, looking at agricultural policy reform, trade liberalization and environmental measures. This all contributes to monitoring and evaluating the effectiveness of policies addressing agri-environmental concerns.
Hazards can take many forms, wholly natural in origin or derived from human activities and interventions. In the Convention on Biological Diversity CBD, ratified by countries defined a legally binding instrument for biodiversity protection and sustainable use of biological resources. The goal of the Convention on Biological Diversity is "the conservation of biological diversity, the sustainable use of its components and the fair and equitable sharing of the benefit arising out of the utilization of genetic resources.
Biological diversity is closely linked to human interests. Biodiversity is highly important for several quite different reasons: It provides a source of significant economic, aesthetic and cultural benefits. The well-being and prosperity of earth's ecological balance as well as human society depend directly on the extent and status of biological diversity.
Naturalism and nature protection: Some difficulties for environmental protection derive from different interpretations and understanding of the idea of nature.
Especially in the consumer's debate on the creation of genetically modified organisms, the idea of the need to protect nature was often not well defined, mainly because of differences in the understanding of the concept of nature, ranging between concepts of wilderness, human environment, flexibility of natural systems  and ideas of naturalism.
Levels of protection may vary as goals range from sustaining ecosystem services to fully preserving endangered species or fragile protected areas. Biotic homogenization that decreases regional biotas and functional diversity would reduce resilience by reducing the available range of species-specific responses to such environmental changes as droughts, contaminants, or invasive species.
The links between environmental protection and human health through the control of direct and indirect health effects of environmental deterioration needs to be factored into these equations, notably with food safety as one of the direct indicators.
Following adoption of hybrid breeding technologies further breeding objectives included methods for the introduction of increased genetic variability using several methods for mutagenesis such as chemical mutagenesis or irradiation as well as various ways of tissue cultures.
The further development resulted in the presently most advanced methods of modern biotechnologies, the production of organism by genetic modification using introduction of defined new or recombinant genetic material by vectors and transformation methods. These organisms are typically named Genetically Modified organisms or GM organisms.
Improved methodology for the development of GM organisms GMOs by homologous recombination may ultimately reduce the potential for unintended effects, including health effects, of the inclusion of new genes randomly in the genome, stemming from present technology. Likewise improved methods for a molecular containment of recombinant genes may reduce problems of unintended gene dispersal. Conflicting assessments and incomplete substantiation of the benefits, risks and limitations of GM food by various scientific, commercial, consumer and public organizations have resulted in national and international controversy regarding their safe use as food and safe release into the environment.
An example is the recent debate on food aid that contained GM material offered to countries in southern Africa in This international debate has often been focused on human health and environmental safety of these new products. At present, only a few food crops are permitted for food use and traded on the international food and feed markets. These include herbicide- and insect-resistant maize Bt maize , herbicide-resistant soybeans, rape canola oilseed and insect- and herbicide-resistant cotton primarily a fibre crop, though refined cottonseed oil is used as food.
In addition, several government authorities have approved varieties of papaya, potato, rice, squash, sugar beet and tomato for food use and environmental release.
Further development of GM crops is likely to produce a range of GM crops with enhanced nutritional profiles. A significant proportion of these traits relates directly to human health, the beta-carotene Vitamin-A precursor rich "golden rice" as the most well-known example. Other examples with health implications are removing allergens and anti-nutrients, altering fatty-acid profiles and increasing the anti-oxidant content. All new products related to such potential health benefits will naturally need to be scrutinized through thorough environmental and food safety risk assessments.
An analysis of risks and effects of food production practices using modern methods of biotechnology needs to reflect on all developments in the area, based on knowledge of modern biology and keeping in mind that the definition of modern biotechnology is often not very standardized. Integrated pest management IPM needs to be seen in the light of modern biotechnology because of the use of advanced bio-technological methods: Definitions of IPM cover a range of approaches: Suitable pest control methods should be used in an integrated manner and pesticides should be used on an "as needed basis" only, and as a last resort component of an IPM strategy.
In such a strategy, the effects of pesticides on human health, the environment, sustainability of the agricultural system and the economy should be carefully considered. According to FAO, IPM programmes are designed to generate independence and increased profits for farmers, and savings on foreign imports for governments.
IPM enables farmers to make informed decisions to manage their crops. Sometimes also organic farming is discussed as a modern technology for food production, where farmers adhering to this idea are aiming for similar objectives like IPM but more clearly pronounce the ideas of integrity, self determination and co evolution. Principles of the environmental risk assessment, ERA: In many national regulations the elements of the ERA for GM food organisms include the biological and molecular characterizations of the genetic insert, the nature and environmental context of the recipient organism, the significance of new traits of the GMO for the environment, and information on the geographical and ecological characteristics of the environment in which the introduction will take place.
The risk assessment focuses especially on potential consequences on the stability and diversity of ecosystems, including putative invasiveness, vertical or horizontal gene flow, other ecological impacts, effects on biodiversity and the impact of presence of GM material in other products. Internationally the concept of familiarity was developed also in the concept of environmental safety of transgenic plants.
Familiarity can also be used to indicate appropriate management practices including whether standard agricultural practices are adequate or whether other management practices are needed to manage the risk OECD, Currently the Cartagena Protocol on Biosafety to the Convention on Biological Diversity is the only international regulatory instrument which deals specifically with the potential adverse effects of genetically modified organisms known as Living Modified Organisms LMOs under the Protocol on the environment.
The Biosafety Protocol covers transboundary movements of any genetically modified foods that meet the definition of LMO. The Protocol establishes a harmonized set of international rules and procedures designed to ensure that countries are provided with the relevant information, through the information exchange system called "Biosafety Clearing-House". This Internet-based information system enables countries to make informed decisions before agreeing to the import of LMOs.
It also ensures that LMO shipments are accompanied by appropriate identification documentation. Furthermore, the scope of its consideration of human health issues is limited, given that its primary focus is biodiversity, in line with the scope of the Convention itself.
Potential unintended effects of GMOs on non target organisms, ecosystems and Biodiversity: Potential risks for the environment include unintended effects on non target organisms, ecosystems and biodiversity. Insect resistant GM crops have been developed by expression of a variety of insecticidal toxins from the bacterium Bacillus thuringiensis Bt.
Detrimental effect on beneficial insects or a faster induction of resistant insects depending on the specific characteristics of the Bt proteins, expression in pollen and areas of cultivation have been considered in the environmental risk assessment ERA of a number of insect protected GM crops.
These questions are considered an issue for monitoring strategies and improved pest resistance management, which inherently can affect food safety in the longer term. Under certain agro-ecological situations, such as a high weed pressure, the use of herbicide tolerant crops has resulted in a reduction in quantity of the herbicides used, in other cases no herbicide reductions or even the need of increased herbicide uses have been reported.
Out-crossing of transgenes has been reported from fields of commercially grown GM plants including oilseed rape and sugar beet, and has been demonstrated in experimental releases for a number of crops including rice and maize.
Out-crossing could result in an undesired transfer of genes such as herbicide resistance genes to non-target crops or weeds creating new weed management problems. The consequences of out-crossing can be expected in regions where a GM crop has a sympatric distribution and synchronized flowering period, that is highly compatible with a weedy or wild relative species as demonstrated e. The possibility that certain genetically engineered fish and other animals may escape, reproduce in the natural environment and introduce recombinant genes into wild populations is a concern of a report of a recent US Academy of Science study .
Genetically engineered insects, shellfish, fish and other animals that can easily escape, are highly mobile and form feral populations easily, are of concern, especially if they are more successful at reproduction than their natural counterparts. For example, it is possible that transgenic salmon with genes engineered to accelerate growth released into the natural environment could compete more successfully for food and mates than wild salmon, thus endangering wild populations.
The use of sterile all-female genetically engineered fish could reduce interbreeding between native populations and farmed populations, a current problem with the use of non-engineered fish in ocean net-pen farming. Sterility eliminates the potential for spread of transgenes in the environment, but does not eliminate all potential for ecological harm.
Monosex triploidy is the best existing method for sterilizing fish and shellfish, although robust triploidy verification procedures are essential. Gene transfer between bacteria belonging to different species, genera or even families has been demonstrated in soil and other systems.
Such gene transfer goes on between ordinary microorganisms in all ecosystems, and has also been demonstrated from GM microorganisms to other microorganisms, e. The transfer of antibiotic genes to microorganisms present in foods and of clinical importance is an unwanted event relative to food safety, while the very low frequency of such transfer most probably leads to very low levels of concern.
Only a limited number of releases of GM microorganisms e. Pseudomonas and Rhizobia have been permitted mainly to explore the spread and the fate of microorganisms in nature.
In some cases released GM bacterial populations have been found to persist in the soil for years. Regional specificity in safety assessments: Contradictory findings as relates benefits or disadvantages for the same GM crop may reflect different agro-ecological conditions in different regions. For example, the use of herbicide resistant crops and the consequent herbicide use could potentially be detrimental in a small sized agricultural area, which has extensive crop rotation and low levels of pest pressure.
However, the moderate herbicide use related to these GM plants could be beneficial in other agricultural situations where it might represent a decrease in herbicide use. Presently, no conclusive evidence on environmental advantages or costs can be generalized from the use of GM crops.
Consequences may vary significantly between different GM traits, crop types and different local conditions including ecological and agro-ecological characteristics.
In , the UK government asked an independent consortium of researchers to investigate how growing genetically modified GM crops might affect the abundance and diversity of farmland wildlife compared with growing conventional varieties of the same crops. The researchers stress that the differences they found do not arise just because the crops have been genetically modified.
They arise because these GM crops give farmers new options for weed control where they use different herbicides and apply them differently. Monitoring of human health and environmental safety: In the future specific GM organisms may gain approvals for widespread production where the approval may not always include the possibility to enter them also in the human food supply.
Examples could be plants or animals used for drug production. In such situations, it will be important to consider whether or not to apply post-market monitoring for unexpected environmental spread of the GM animals or animals and their transgenes in the event that these would pose food safety hazards. A prerequisite for any kind of monitoring are tools to identity or trace GMOs or products derived from GMOs in the environment or food-chain.
Detection techniques such as PCR are in place in a number of countries to monitor the presence of GMOs in foodstuffs, to enable the enforcement of GM labelling requirements and for the monitoring of effects on the environment. Attempts to standardize analytical methods for tracing GMOs have been initiated e. The need to assess indirect effects of the use of GMOs in food production has been emphasized by many countries. For example, the production of chemicals or enzymes from contained GM micro-organisms e.
A further example of beneficial human environmental outcomes of the use of GM crops is the reduction in the use, environmental contamination and human exposure to pesticides demonstrated in some areas. This has been demonstrated especially through the use of pesticide resistant Bt cotton, which has been shown to decrease pesticide poisoning in farm workers . Out-crossing of GM plants with conventional crops or wild relatives, as well as the contamination of conventional crops with GM material, can have an indirect effect on food safety and food security by contamination of genetic resources .
The Codex guidelines for the safety assessment of GM foods include the analysis of potential unintended effects, where effects on the environment may result in unintended, indirect effects on human health. Crop breeding strategies are highly dependent upon preservation of diversity of crops and wild relatives. Many methods of conventional and modern biotechnology can interfere with diversity of organisms which have relevance for further breeding.
In crops these methods can often concentrate on the further improvement of few elite lines only. The majority of locally adapted land races e.
Also the system for the protection of intellectual property rights interferes with crop diversity. There is growing scientific and public concern about a rapid decline of diversity, e. On the other hand modern methods of biotechnology can be beneficial for enabling diversity in scenarios where possibilities of conventional breeding are difficult because of sterility and pests, e. Historically, plant genetic resources were freely provided by developing countries to gene-banks world-wide.
Now international policy attaches importance to national ownership of such resources. An important aspect for the future potential of agricultural research is access to genetic resources for researchers on terms that recognize the contributions made by farmers to the conservation and sustainable utilization of these resources.
The International Treaty on Plant Genetic Resources adopted at a conference by the Food and Agriculture Organization in November , provides the legal framework for dealing with the resources on which food security and sustainable agriculture depend. The Treaty gives a directive on the conservation and sustainable use of plant genetic resources for food and agriculture making provision for the fair and equitable sharing of the benefits arising out of their use, in harmony with the United Nations Convention on Biological Diversity CBD.
The Treaty also addresses farmers' rights. The Treaty establishes a Multilateral System of Facilitated Access and Benefit-sharing MLS for key crops, emphasizing the interdependency of countries in terms of plant genetic resources for food and agriculture.
The developing countries rich in genetic resources are encouraged to place germplasm in the MLS. The users of the material will sign a Material Transfer Agreement, incorporating the conditions for access and benefit sharing through a fund established under the Treaty.
In return, the owners of the genetic resources would get a share of the benefits arising from their use and development in the way of information, technology transfer and capacity building. Agency for International Development reported that between and the year the world lost 22 percent of its high-potential agricultural land. That's , square miles, an area equal in size to Alaska. The loss is alarming because, as population pressures mount, agricultural production will have to expand onto medium- and low-potential lands that are not only less productive but also more fragile and susceptible to degradation.
Soil is degraded mainly through deforestation, agricultural activities, overgrazing, and overexploitation. Biophysical manifestations include erosion and loss of moisture-holding capacity. But more important, and more complex, are the social and economic aspects. Indeed, some view land degradation as a socioeconomic rather than biophysical problem.
For example, population growth increases demand for land on which to grow crops, which often leads to deforestation, shorter fallow periods, and continuous cropping. Short-sighted economic policies often make the problem worse by encouraging farmers to clear new land for cultivation rather than to protect land already under cultivation.
Insecure land tenure arrangements discourage farmers from making long-term investments needed for resource conservation. The Impacts of trade liberalization: The implementation or reform of agricultural and trade policy creates a complicated set of environmental effects - some negative, some positive, and in some cases linked to food safety issues. The effect of freer agricultural trade on environmental quality depends on a number of factors, such as the mix of post-reform commodities, level of output, changes in production inputs, land use, technical change, and the capacity of the natural resource base to assimilate production impacts.
The additional effect of such changes related to food safety will in many cases relate to the existence of food safety systems and experience related to the new or increase food commodity production.
Freer trade improves market access for goods previously governed by quantity restrictions such as quotas and other non-tariff barriers and aligns domestic prices closer to world prices. Resource reallocation occurs as prices adjust to market conditions and reflect the availability of resources such as arable land, labour, and other farming inputs.
As prices change, farmers respond by altering their crop mix and their input use, buying or selling land, and investing in new machinery. In addition, trade and health considerations are intimately connected. The use of international standards for traded food, focusing on food safety, but in the future also most likely on environmental issues, will have the potential to improve not only internationally traded food but also local food, and thereby the health of local consumers.
This in turn would then favour both health and social and economic development - a true win-win situation. This Facility will hopefully provide the means for developing countries to strengthen their systems to comply with international standards to the benefit of both exported and locally consumed food.
International agreements related to nature and food production are summarized in a report from FAO on ethical issues in food and agriculture. They include the value of food, the value of enhanced well-being, the value of human health, the value of natural resources, and the value of nature, whereas the Convention on Biological Diversity recognizes that nature itself is to be valued for what it is.
The summary of these objectives shows that all principle arguments usually discussed in a risk benefit evaluation of food biotechnology, especially enhanced productivity for increased food production, equity, health and nature protection, interfere with each other, thus requiring a high level of ethical consideration.
There is international agreement that risk assessment, risk management and risk communication are central elements in the management of possibly emerging risks of new technologies for food production where risk assessment needs to be done based on "sound science".
But discussions on the use of precaution by some countries referred to as the precautionary principle and the need to respect legitimate factors other than the scientific assessment of risk have turned out to be controversial .
Science and Ethics Rome, The experts agreed that risk assessment is based on science, but scientific evidence and analysis cannot always provide immediate answers to questions posed. Much scientific evidence is tentative, as the established processes of science include checking and re checking outcomes in order to obtain the required level of confidence.
Decisions usually are defended as based on "science," and sometimes on economic costs and benefits as well, which offer seemingly objective, verifiable evidence that the policy choice is "correct. The emphasis on science and the exclusion of ethical argument as the basis for decisions may polarize the scientific debate.
A cross sectoral group of scientists, NGOs and industry formulated the safety first approach asking for interactive negotiation between research, industry, government and consumers to formulate safety standards. These standards would make safety a criterion in discussions on developments from the beginning and not at the end before product notification and include post market monitoring, training and stewardship.
Products produced with different methods of modern biotechnology are already produced for local or international markets. Crops, animals or microorganism have been improved according to agricultural objectives where these organisms may display specific characteristics in regard to safety or usefulness in different agro- ecological, socio-economic or cultural areas.
A globalized market for food production will most likely trade products of these organisms internationally and the safety measures of the Biosafety Protocol will be of importance in risk prevention.
However, possibilities of the protocol are restricted to transboundary movements of LMOs and direct effects on diversity. Furthermore, sufficient technical capacities for coherent analysis may be difficult to achieve in many developing countries and the need for coordinated local as well as international information exchange on complex parameters will require sophisticated technical and scientific capacities. The capacity of the Codex Alimentarius Commission to continue its work on internationally agreed principles and guidelines for a food safety risk analysis framework will be key to a truly global development in this area of integrating the different areas of assessment of new agricultural technologies and ensuring that human health considerations will remain at the core.
This will ultimately need measures for capacity building in some countries as well as the intensive engagement of international bodies in coordinated monitoring activities, data collection and data analysis. An engaged cooperation of international organizations, especially UN-bodies will be essential for a successful and equitable development in this direction.
The malicious contamination of food for political, financial and other purposes is a real and current threat, and deliberate contamination of food at one location could have global public health implications. Member States of WHO have expressed concern that chemical, biological or radionuclear agents might be introduced into food and other media to deliberately to harm civilian populations and have requested the Organization to provide tools and support to increase their capacity to respond.
In response, WHO has prepared various guidelines, including guidance to prevent and respond to intentional contamination of food. While all food safety emergencies, including intentional and unintentional incidents, may be managed by the existing food safety infrastructure, sensible preventive measures coupled with basic preparedness are needed to address threats posed by deliberate contamination.
Countries should integrate consideration of acts of food sabotage into existing programmes for assuring the safety of their food supplies.
Strengthening of food safety infrastructure will serve to increase countries' capacity to reduce the burden of all food-borne illness caused by chemical and microbial agents and to respond to all contamination incidents.
Improved linkages with existing communicable disease control systems will also ensure that surveillance, preparedness and response systems include the necessary metrics to identify food-borne outbreaks in a timely manner and provide relevant information to facilitate an effective and rapid response. In order to respond effectively and rapidly, countries require alert, preparedness and response systems to public health threats from actual or threatened intentional contamination of the food supply.
Coordination with WHO, FAO and other international and regional organizations regarding incidents involving intentional contamination should be considered as an integral part of strengthening of national systems to respond to all food safety emergencies. Threats from criminals and other anti-social groups who target the safety of the food supply are already a reality. During the past two decades, WHO Member States have expressed increasing concern about the possibility that chemical and biological agents and radionuclear materials might deliberately be used to harm civilian populations.
In recent years, the health ministries of several countries have increased their state of alert for intentional malevolent use of agents that may be spread through air, water or food.
In , the World Health Assembly in recognizing these threats against civilian populations, requested WHO to provide tools and support to countries in strengthening their national systems to respond to the deliberate use of biological, chemical or radionuclear agents . It also requested WHO to continue to issue international guidance and technical information on recommended public health measures to deal with potential incidents.
All countries must have basic systems to prevent or deter deliberate contamination of their food supplies and, if an incident occurs, to respond rapidly to minimize potential health, economic and other adverse effects of such contamination.
However, specific countermeasures should be seen as only one aspect of a broader, comprehensive food safety programme, in national and global contexts. The WHO Global Food Safety Strategy  comprises a preventive approach to food safety, with increased surveillance and more rapid response to outbreaks of food-borne illness and chemical contamination incidents.
This approach could substantially expand the abilities of countries to protect the safety of their food supplies against natural and accidental threats, while providing a framework for addressing intentional contamination of food. The chemical agents in question are man-made or natural toxins, and the biological agents referred to are pathogenic microorganisms, including viruses, bacteria and parasites, that may be communicably infectious or non-infectious.
Radionuclear agents are defined in this context as radioactive chemicals capable of causing injury when present at unacceptable levels. This paper covers all foods, including water used in the preparation of food, as well as bottled water.
As with all health and safety problems, prevention is usually the most desirable option. Prevention is considered first line of defence against intentional contamination. The key to prevention is awareness of this potential threat and the implementation of basic security and precautionary measures. Working in cooperation with government, the food industry is in the best position to rapidly address such threats throughout the food supply system from production to consumption.
Government food safety authorities may provide necessary guidance and other coordination functions to assist industry, as in the case of product tracing and recall. As production methods and quality programmes are often proprietary, the food industry has both the knowledge and the capacity to reduce the likelihood of deliberate contamination of food, from the raw materials to product distribution. Governments should support industry in strengthening existing food safety management systems, to include consideration of deliberate contamination.
Governments also have a role in promoting preventive food safety, through various voluntary and regulatory mechanisms . It is important to note that a number of the preventive activities described in this paper relate to 'industrialized' food production systems.
Although industrialized production probably also present the most likely targets for intentional contamination, it is very likely that more traditional production systems, including systems with short distribution lines, present problems that need separate consideration. Food can be contaminated deliberately by chemical, biological or radionuclear agents at any point in the food chain. Food safety management programmes offer opportunities for the prevention, detection and control of food sabotage.
Understanding the relationships between the production system, ingredients, people, utensils, equipment and machinery can help in identifying where critical failures of the system might occur. Methods of sabotage and the extent of a threat might be identified as a part of this analysis and would provide the basis for a risk analysis. Typical food safety management programmes within the food industry, include good agricultural and manufacturing practices and 'hazard analysis and critical control point' HACCP systems.
Newer systems based on a scientific assessment of the risk are now increasingly being used to develop risk reduction options along the food supply continuum from farm to table. Governments should work closely with industry to incorporate prevention and response to intentional contamination into food safety management programmes.
Not all countries have the infrastructure needed to assist industry, especially small and less developed businesses, to apply such programmes throughout the food production, processing and preparation continuum. Capacity building for such competence is vital for the prevention of both intentional and unintentional contamination of food.
The generic actions that may be taken by governments to assist industry in this respect include:. Prevention of intentional contamination does not always require high technology or great expense. Increased awareness of the problem and enhanced vigilance are among the effective measures that can be taken. Awareness can be heightened by auditing food safety management programmes.
In the event of an incident, information from early surveillance could be shared with the food industry to facilitate prompt action to address consumer concerns and contain and mitigate the threat. The knowledge and capacity to prevent deliberate sabotage of food lies mainly with the food industry and must be applied throughout the food chain. Potential contamination with chemical and biological agents and radionuclear materials and interruption of food supplies need to be considered in the development and review of food safety management programmes, which may vary from rudimentary to well developed.
Opportunities for deliberate contamination of food can be minimized by increasing the security for both people and premises.
All segments of the food industry should consider improving security and response plans for their establishments. For example, sources of raw materials and storage facilities and transport systems could be safeguarded; access to all critical areas in production, processing, transport and storage could be controlled and documented to minimize opportunities for contamination. Regarding personnel, employers could consider screening their staff to ensure that their qualifications and background are compatible with their work and responsibilities.
Sanitation, maintenance and inspection workers, who have access to critical areas, could also be screened from a security perspective. Appropriate mechanisms could be established to allow staff to report suspicious behaviour and activities. While it is impossible to describe all the possible scenarios for food sabotage, WHO has developed basic guidance for the food industry for strengthening food safety management programmes to prevent intentional contamination of food with harmful agents .
This guidance offers a range of options that should be considered by industry, taking into account available resources and the perceived threat. Plausible risks need to be considered at every point in the food chain to ensure the safety of the food produced.
A number of useful documents prepared by certain countries  ,  ,  and industries  offer examples and guidance for analysing risks in the production and processing of specific foods.
Not all of these documents will be applicable in their entirety to smaller, developing businesses, but the general principles of assessing vulnerability apply across all businesses and sectors  , . While preventive measures are essential, the opportunities for intentional contamination of food are just too numerous to ever be able to completely prevent such incidents.
However, effective and rapid monitoring and surveillance programmes coupled with preparedness planning can do much to respond to such threats. Many governments have, or are developing, food safety infrastructures to ensure that food produced for both domestic consumption and export meets acceptable safety standards. Strengthening national food safety programmes requires that national policies and resources to support the infrastructure are in place and that food legislation, food contamination monitoring laboratories, food inspection, food-borne disease surveillance, education and training are adequate and up to date.
Above all, the possibility of intentional contamination needs to be an integral part of safety considerations. While most of the knowledge and capacity to prevent food safety emergencies lies within the food industry, governments have a lead responsibility for detecting and responding to actual or threatened food contamination incidents as well as other food safety emergencies.
In the event of an intentional food safety emergency, the potential consequences to public health, the economy and social or political stability must be managed by an effective, rapid emergency response system, at all levels.
The effectiveness of a response depends to a great extent on preparedness plans that are developed and implemented long before any event occurs. Public health preparedness planning for emergency situations has been considered in some detail in various WHO publications and is therefore not discussed in detail in this document. The nature of a preparedness and response system is based on an assessment of specific threats of deliberate food contamination and their priorities in relation to other public health problems.
The priorities are determined as part of an assessment of vulnerability performed as part of the development of preparedness plans for intentional contamination. Threats could be ranked from high to low, on the basis of their impact on health and their potential social, economic and political consequences. Vulnerability is assessed on the basis of the prevailing scientific, economic, political and social circumstances of a country, to measure the extent of a threat and to set priorities for resources.
Priorities must be set to ensure that the action taken to deal with the threat is commensurate with the severity of the inherent consequences of the threat. The purpose of an assessment of vulnerability is to identify the properties and potential consequences of deliberate contamination of food by harmful agents, to identify relative priorities and to commit national resources in a proportion consistent with these priorities.
Technical experts in food and food safety should participate in any assessment of vulnerability specific for intentional contamination. Information on the toxicology of chemicals and the characteristics of microbial agents is a necessary component of such an assessment, together with an assessment of potential exposure, which will determine the potential impact of the agent.
Response to emergencies caused by intentional contamination of food has common features to emergencies caused by unintentional contamination. Often the two cases cannot be distinguished, especially during the early phases of an outbreak. For these reasons, preparedness plans should include response to both intentional and unintentional incidents. Where preparedness plans already exist food safety emergencies, intentional contamination of food needs to be integrated into existing plans, making maximum use of existing emergency response infrastructure and resources.
The resources and protocols for a medical response, including rapid transport, supplies, personnel and patient evacuation, are an integral part of communicable disease preparedness, and these have been described elsewhere. In planning for food safety emergencies, the following points are emphasized:. Planning should consider the ability of the surveillance and monitoring systems to rapidly detect food safety emergencies, including those caused deliberately;.
Investigation of a potential outbreak identified by surveillance should include identification of the food and the responsible agent in the food; and,. Response to an incident, where the source or mode of transmission is unknown, should be made concurrently with all the necessary food safety components until the role of food can be ruled out. For incidents involving intentional contamination of food, effective interaction between emergency response and law enforcement components is very important.
Preparedness planning may include specific requirements of the criminal justice system, such as a signed chain of custody for any specimens and other evidence. Preparedness plans should be tested in exercises involving agencies responsible for emergency responses to intentional food contamination.
Any new components should be tested for effective response to intentional incidents. Evaluation of the results of real incidents and emergency response exercises should be used to identify the need for further resources, refine the roles of various agencies and their interaction and improve emergency plans.
The performance of surveillance systems for detecting food-borne disease clusters and epidemiological investigations to identify the food and hazardous agent give an indication of the capacity of the system to respond to intentional incidents.
Timely response to food emergencies requires effective linkage of preparedness planning and emergency response systems in all relevant agencies. Linkages with food safety authorities are needed to provide specialized support related to an investigation that may involve food. Availability of qualified food safety inspectors and laboratories are important requirements for preparedness. For example, the timely sampling, transport and analysis of suspected foods should be addressed as part of preparedness planning.
Countries need to inventory their laboratory capacities for possible threat agents. Public health preparedness and response systems focus mainly on communicable diseases, and most emergency response systems do not yet include consideration of the use of food as a vehicle for threat agents. Few countries are able to respond rapidly and effectively to intentional food contamination in their current state of development.
Food safety emergency response may be initiated by either a plausible threat or an actual act of deliberate contamination of food. An effective public health response to a deliberate food contamination incident will depend on the timeliness and quality of communication among numerous agencies and sectors, including health services, public health authorities at local and national level, clinicians, infectious disease specialists, laboratories, poison information centres, forensic pathologists, other agencies and organizations and the food industry.
An effective emergency response must also be tailored to the circumstance and should include links with law enforcement and intelligence agencies, tracing and food recall systems, risk assessment specialists and the food industry as well as the more traditional sectors of health care providers, laboratories and emergency services. Linkages between existing national alert and response systems and food safety systems allow effective detection of and response to such incidents.
Improved links with food safety agencies will allow access to relevant information about food and about methods and analytical techniques for testing food and harmful agents. Experts in food safety could assess the risks associated with chemicals and microbiological hazards to ensure that the response is proportional to the risk. Identification and recall of affected foods are important features of a food safety emergency response.
Tracing information is necessary for estimating the scale of potential exposure and for removing the affected food from sale. It may also assist in a criminal investigation of a food contamination incident. Recalls are usually implemented by the food industry in cooperation with food safety authorities.
Quarantine and customs agencies have information about food imports necessary for tracing and recall and can undertake rapid seizure of food at the point of entry. Coverage 'from farm to fork' needs to be incorporated into response planning for food safety emergencies, including the intentional contamination of the food supply.