Basic Tissue Types

Being Prepared is about the Future - yours.

How To Opt Out From ‘Smart’ Meters (Before & After Measurements)
This course is for non-science majors. Meditation is another method that can help people overcome depression and anxiety. This course provides a broad and intensive investigation of visual narratives through photographic representation. A mixture of raw almonds, cashews, pecans, filberts, Brazil nuts, walnuts, sunflower seeds, pumpkin seeds, and sesame seeds is recommended to supplement protein during the first six months when meat proteins are severely restricted. Such is the desperation of central bankers to avoid a recession or even another depression that they are simply doing everything they can to rig market outcomes, simultaneously not allowing the markets to be the free regulator of risk. Thesis, University of Paris, Paris, France. Reconnect with the natural world - even if you live in a city, just going for a walk and passing a tree is connecting and centering.

Solution: Get Informed Before You Demonstrate

Topic Index

In , Erhard Fernholz discovered the chemical structure of vitamin E and then he tragically disappeared. In , rationing in the United Kingdom during and after World War II took place according to nutritional principles drawn up by Elsie Widdowson and others. In , The U. Department of Agriculture introduced the Food Guide Pyramid. The list of nutrients that people are known to require is, in the words of Marion Nestle , "almost certainly incomplete".

Some nutrients can be stored - the fat-soluble vitamins - while others are required more or less continuously. Poor health can be caused by a lack of required nutrients, or for some vitamins and minerals, too much of a required nutrient.

The macronutrients are carbohydrates , fiber , fats , protein , and water. Some of the structural material can be used to generate energy internally, and in either case it is measured in Joules or kilocalories often called "Calories" and written with a capital C to distinguish them from little 'c' calories. Vitamins, minerals, fiber, and water do not provide energy, but are required for other reasons.

Molecules of carbohydrates and fats consist of carbon, hydrogen, and oxygen atoms. Carbohydrates range from simple monosaccharides glucose, fructose and galactose to complex polysaccharides starch. Fats are triglycerides , made of assorted fatty acid monomers bound to a glycerol backbone. Some fatty acids, but not all, are essential in the diet: Protein molecules contain nitrogen atoms in addition to carbon, oxygen, and hydrogen. The fundamental components of protein are nitrogen-containing amino acids , some of which are essential in the sense that humans cannot make them internally.

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. By breaking down existing protein, the carbon skeleton of the various amino acids can be metabolized to intermediates in cellular respiration; the remaining ammonia is discarded primarily as urea in urine.

Carbohydrates may be classified as monosaccharides , disaccharides , or polysaccharides depending on the number of monomer sugar units they contain. They constitute a large part of foods such as rice , noodles , bread , and other grain -based products, also potatoes , yams, beans, fruits, fruit juices and vegetables.

Monosaccharides, disaccharides, and polysaccharides contain one, two, and three or more sugar units, respectively. Polysaccharides are often referred to as complex carbohydrates because they are typically long, multiple branched chains of sugar units.

Traditionally, simple carbohydrates are believed to be absorbed quickly, and therefore to raise blood-glucose levels more rapidly than complex carbohydrates. This, however, is not accurate. Dietary fiber is a carbohydrate that is incompletely absorbed in humans and in some animals. Like all carbohydrates, when it is metabolized it can produce four Calories kilocalories of energy per gram.

However, in most circumstances it accounts for less than that because of its limited absorption and digestibility. Dietary fiber consists mainly of cellulose, a large carbohydrate polymer which is indigestible as humans do not have the required enzymes to disassemble it. There are two subcategories: Whole grains, fruits especially plums , prunes , and figs , and vegetables are good sources of dietary fiber.

There are many health benefits of a high-fiber diet. Dietary fiber helps reduce the chance of gastrointestinal problems such as constipation and diarrhea by increasing the weight and size of stool and softening it. Insoluble fiber, found in whole wheat flour , nuts and vegetables, especially stimulates peristalsis ;— the rhythmic muscular contractions of the intestines, which move digest along the digestive tract.

Soluble fiber, found in oats, peas, beans, and many fruits, dissolves in water in the intestinal tract to produce a gel that slows the movement of food through the intestines. This may help lower blood glucose levels because it can slow the absorption of sugar. Additionally, fiber, perhaps especially that from whole grains, is thought to possibly help lessen insulin spikes, and therefore reduce the risk of type 2 diabetes. The link between increased fiber consumption and a decreased risk of colorectal cancer is still uncertain.

A molecule of dietary fat typically consists of several fatty acids containing long chains of carbon and hydrogen atoms , bonded to a glycerol. They are typically found as triglycerides three fatty acids attached to one glycerol backbone. Fats may be classified as saturated or unsaturated depending on the detailed structure of the fatty acids involved.

Saturated fats have all of the carbon atoms in their fatty acid chains bonded to hydrogen atoms, whereas unsaturated fats have some of these carbon atoms double-bonded , so their molecules have relatively fewer hydrogen atoms than a saturated fatty acid of the same length.

Unsaturated fats may be further classified as monounsaturated one double-bond or polyunsaturated many double-bonds. Furthermore, depending on the location of the double-bond in the fatty acid chain, unsaturated fatty acids are classified as omega-3 or omega-6 fatty acids.

Trans fats are a type of unsaturated fat with trans -isomer bonds; these are rare in nature and in foods from natural sources; they are typically created in an industrial process called partial hydrogenation. There are nine kilocalories in each gram of fat. Fatty acids such as conjugated linoleic acid , catalpic acid, eleostearic acid and punicic acid , in addition to providing energy, represent potent immune modulatory molecules. Saturated fats typically from animal sources have been a staple in many world cultures for millennia.

Saturated and some trans fats are typically solid at room temperature such as butter or lard , while unsaturated fats are typically liquids such as olive oil or flaxseed oil.

Trans fats are very rare in nature, and have been shown to be highly detrimental to human health, but have properties useful in the food processing industry, such as rancidity resistance. Most fatty acids are non-essential, meaning the body can produce them as needed, generally from other fatty acids and always by expending energy to do so.

However, in humans, at least two fatty acids are essential and must be included in the diet. An appropriate balance of essential fatty acids— omega-3 and omega-6 fatty acids —seems also important for health, although definitive experimental demonstration has been elusive. Both of these "omega" long-chain polyunsaturated fatty acids are substrates for a class of eicosanoids known as prostaglandins , which have roles throughout the human body.

They are hormones , in some respects. The omega-3 eicosapentaenoic acid EPA , which can be made in the human body from the omega-3 essential fatty acid alpha-linolenic acid ALA , or taken in through marine food sources, serves as a building block for series 3 prostaglandins e.

The omega-6 dihomo-gamma-linolenic acid DGLA serves as a building block for series 1 prostaglandins e. An appropriately balanced intake of omega-3 and omega-6 partly determines the relative production of different prostaglandins, which is one reason why a balance between omega-3 and omega-6 is believed important for cardiovascular health.

In industrialized societies, people typically consume large amounts of processed vegetable oils, which have reduced amounts of the essential fatty acids along with too much of omega-6 fatty acids relative to omega-3 fatty acids. Moreover, the conversion desaturation of DGLA to AA is controlled by the enzyme deltadesaturase , which in turn is controlled by hormones such as insulin up-regulation and glucagon down-regulation. The amount and type of carbohydrates consumed, along with some types of amino acid, can influence processes involving insulin, glucagon, and other hormones; therefore, the ratio of omega-3 versus omega-6 has wide effects on general health, and specific effects on immune function and inflammation , and mitosis i.

Proteins are structural materials in much of the animal body e. They also form the enzymes that control chemical reactions throughout the body. Each protein molecule is composed of amino acids , which are characterized by inclusion of nitrogen and sometimes sulphur these components are responsible for the distinctive smell of burning protein, such as the keratin in hair.

The body requires amino acids to produce new proteins protein retention and to replace damaged proteins maintenance. As there is no protein or amino acid storage provision, amino acids must be present in the diet. Excess amino acids are discarded, typically in the urine. For all animals, some amino acids are essential an animal cannot produce them internally and some are non-essential the animal can produce them from other nitrogen-containing compounds.

About twenty amino acids are found in the human body, and about ten of these are essential and, therefore, must be included in the diet. A diet that contains adequate amounts of amino acids especially those that are essential is particularly important in some situations: A complete protein source contains all the essential amino acids; an incomplete protein source lacks one or more of the essential amino acids.

It is possible with protein combinations of two incomplete protein sources e. However, complementary sources of protein do not need to be eaten at the same meal to be used together by the body. Water is excreted from the body in multiple forms; including urine and feces , sweating , and by water vapour in the exhaled breath. Therefore, it is necessary to adequately rehydrate to replace lost fluids.

Early recommendations for the quantity of water required for maintenance of good health suggested that 6—8 glasses of water daily is the minimum to maintain proper hydration. Most of this quantity is contained in prepared foods. For healthful hydration, the current EFSA guidelines recommend total water intakes of 2.

These reference values include water from drinking water, other beverages, and from food. The EFSA panel also determined intakes for different populations.

Recommended intake volumes in the elderly are the same as for adults as despite lower energy consumption, the water requirement of this group is increased due to a reduction in renal concentrating capacity.

Dehydration and over-hydration - too little and too much water, respectively - can have harmful consequences.

Drinking too much water is one of the possible causes of hyponatremia , i. Pure ethanol provides 7 calories per gram.

For distilled spirits , a standard serving in the United States is 1. A 5 ounce serving of wine contains to calories. A 12 ounce serving of beer contains 95 to calories. Alcoholic beverages are considered empty calorie foods because other than calories, these contribute no essential nutrients. The micronutrients are minerals , vitamins , and others.

Dietary minerals are inorganic chemical elements required by living organisms, [70] other than the four elements carbon , hydrogen , nitrogen , and oxygen that are present in nearly all organic molecules. The term "mineral" is archaic, since the intent is to describe simply the less common elements in the diet. Some are heavier than the four just mentioned, including several metals , which often occur as ions in the body.

Some dietitians recommend that these be supplied from foods in which they occur naturally, or at least as complex compounds, or sometimes even from natural inorganic sources such as calcium carbonate from ground oyster shells. Some minerals are absorbed much more readily in the ionic forms found in such sources. On the other hand, minerals are often artificially added to the diet as supplements; the most famous is likely iodine in iodized salt which prevents goiter.

Many elements are essential in relative quantity; they are usually called "bulk minerals". Some are structural, but many play a role as electrolytes. Many elements are required in trace amounts, usually because they play a catalytic role in enzymes. Vitamins are essential nutrients, [70] necessary in the diet for good health. Vitamin D is an exception, as it can be synthesized in the skin in the presence of UVB radiation , and many animal species can synthesize vitamin C.

Vitamin deficiencies may result in disease conditions, including goitre , scurvy , osteoporosis , impaired immune system, disorders of cell metabolism, certain forms of cancer, symptoms of premature aging, and poor psychological health , among many others.

Phytochemicals such as polyphenols are compounds produced naturally in plants phyto means "plant" in Greek. In general, the term is used to refer to compounds which do not appear to be nutritionally essential and yet may have positive impacts on health. To date, there is no conclusive evidence in humans that polyphenols or other non-nutrient compounds from plants have health benefit effects.

While initial studies sought to reveal if nutrient antioxidant supplements might promote health, one meta-analysis concluded that supplementation with vitamins A and E and beta-carotene did not convey any benefits and may in fact increase risk of death.

Vitamin C and selenium supplements did not impact mortality rate. Health effects of non-nutrient phytochemicals such as polyphenols were not assessed in this review. Animal intestines contain a large population of gut flora. In humans, the four dominant phyla are Firmicutes , Bacteroidetes , Actinobacteria , and Proteobacteria. Bacteria in the large intestine perform many important functions for humans, including breaking down and aiding in the absorption of fermentable fiber, stimulating cell growth, repressing the growth of harmful bacteria, training the immune system to respond only to pathogens, producing vitamin B 12 , and defending against some infectious diseases.

There is not yet a scientific consensus as to health benefits accruing from probiotics or prebiotics. Carnivore and herbivore diets are contrasting, with basic nitrogen and carbon proportions vary for their particular foods. Many herbivores rely on bacterial fermentation to create digestible nutrients from indigestible plant cellulose, while obligate carnivores must eat animal meats to obtain certain vitamins or nutrients their bodies cannot otherwise synthesize.

Plant nutrition is the study of the chemical elements that are necessary for plant growth. Some elements are directly involved in plant metabolism. However, this principle does not account for the so-called beneficial elements, whose presence, while not required, has clear positive effects on plant growth.

A nutrient that is able to limit plant growth according to Liebig's law of the minimum is considered an essential plant nutrient if the plant cannot complete its full life cycle without it. There are 16 essential plant soil nutrients, besides the three major elemental nutrients carbon and oxygen that are obtained by photosynthetic plants from carbon dioxide in air, and hydrogen , which is obtained from water.

Plants uptake essential elements from the soil through their roots and from the air consisting of mainly nitrogen and oxygen through their leaves. Green plants obtain their carbohydrate supply from the carbon dioxide in the air by the process of photosynthesis. Carbon and oxygen are absorbed from the air, while other nutrients are absorbed from the soil.

These hydrogen ions displace cations attached to negatively charged soil particles so that the cations are available for uptake by the root. In the leaves, stomata open to take in carbon dioxide and expel oxygen. The carbon dioxide molecules are used as the carbon source in photosynthesis. Although nitrogen is plentiful in the Earth's atmosphere, very few plants can use this directly.

Most plants, therefore, require nitrogen compounds to be present in the soil in which they grow. This is made possible by the fact that largely inert atmospheric nitrogen is changed in a nitrogen fixation process to biologically usable forms in the soil by bacteria.

Plant nutrition is a difficult subject to understand completely, partially because of the variation between different plants and even between different species or individuals of a given clone. Elements present at low levels may cause deficiency symptoms, and toxicity is possible at levels that are too high.

Furthermore, deficiency of one element may present as symptoms of toxicity from another element, and vice versa. Canada's Food Guide is an example of a government-run nutrition program. Produced by Health Canada , the guide advises food quantities, provides education on balanced nutrition, and promotes physical activity in accordance with government-mandated nutrient needs. Like other nutrition programs around the world, Canada's Food Guide divides nutrition into four main food groups: 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 [46]. 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 [51].

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 [52]. 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 [60]. 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 [65].

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 [67] 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 [68]. 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 [69]. 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 [70] , [71] , [72] and industries [73] 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 [74] , [75].

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. Muscle Tissue is specialized for gross movement by means of cellular contraction.

Embryonically, muscle derives from mesoderm or mesenchyme. A note on pathology nomenclature: The names of neoplasms reflect the fundamental nature of their source tissues.

Thus a carcinoma is a cancer of epithelial origin, while a sarcoma is a cancer of mesenchymal connective tissue or muscle origin. The parenchyma of an organ consists of that tissue which conducts the specific function of the organ and which usually comprises the bulk of the organ. Stroma is everything else -- connective tissue , blood vessels, nerves, ducts. Because organ-specific function usually centers on parenchymal cells, histological and physiological accounts often emphasize parenchyma.

Unfortunately, stroma is commonly ignored as just boring background tissue. Pay attention to the stroma. No organ can function without the mechanical and nutritional support provided by the stroma. If an organ is inflamed, the signs of inflammation appear first in the stroma.

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