Pesticide on food

Pesticide residues consist of chemicals that might occur in a commodity as a result of application of a pesticide. Such chemicals typically correspond to compounds for which a regulatory agency has or will set a tolerance, i.e., a maximum residue limit, specific to the commodity. In either a field study or a market basket survey, residues to be determined will be those which result from application of the specific pesticide that the study is intended to support. A market basket survey, however, might be intended to support not just one but several different pesticides of the same or different chemical classes. In addition, a market basket survey might include pesticides not used in the USA but for which import tolerances exist. For example, some uses of the parathion family of pesticides on food products have been abandoned in the USA but remain in other countries that export the products to the USA. A market basket survey offers a means to evaluate actual dietary exposures to residues of such pesticides. In addition, tolerance expressions frequently include multiple compounds, all of which must typically be determined in residue field trials. The sponsor of the market basket survey must decide whether to analyze for all compounds in the applicable tolerance expression or to restrict the program to selected analytes, such as the active ingredient. 

Bennett, R.S., Jr. and H.H. Prince. 1981. Influence of agricultural pesticides on food preference and consumption by ring-necked pheasants. Jour. Wildl. Manage. 45 74-82. 

Approximately 55 different commercial formulations of chlordecone have been prepared since its introduction in 1958 (Epstein 1978). The major form of chlordecone, which was used as a pesticide on food products, was a wettable powder (50% chlordecone) (Epstein 1978). Formulations of chlordecone commonly used for nonfood products were in the form of granules and dusts containing 5% or 10% active ingredient (Epstein 1978). Other formulations of chlordecone contained the following percentages of active ingredient 0.125% (used in the United States in ant and roach traps), 5% (exported for banana and potato dusting), 25% (used in the United States in ant and roach bait), 50% (used to control mole crickets in Florida), and 90% (exported to Europe for conversion to kelevan for use on Colorado potato beetles in eastern European countries) (Epstein 1978). 

While all nations of the world possess the sovereign right to establish their own acceptable levels for pesticide residues in foods, many lack the resources to develop their own regulatory programs and instead rely upon a set of international standards developed by the Codex Alimentarius Commission, frequently referred to as Codex. The Codex international standards are termed maximum residue limits (MRLs) and, like U.S. tolerances, are established primarily as enforcement tools for determining whether pesticide applications are made according to established directions. While many countries have adopted Codex MRLs, others, such as the U.S. and several Asian countries, rely on their own standards. Thus, there is no uniformity among the world with respect to allowable levels of pesticides on foods. A pesticide-commodity... 

My symptoms were painful eyes, numbness in my bottom lip, shortness of breath and weight loss. When I also became sensitive to my mattress and could no longer wear my clothes, the situation became unlivable. In July 2005, it turned out from testing that I also had a serious intolerance to pesticides on food and to various food products. 

Improved crop varieties and protection methods have demanded the application of many herbicides and fungicides to attain increased crop yields, decreased food costs, and enhanced appearance of food. Without proper controls, however, the residues of some pesticides on foods can create potential health risks. Proper application of herbicides and fungicides (as discussed previously) has not only lead to increased crop yield but also has reduced the hazards of persistent pesticides, such as organochlorine insecticides. However, further studies are needed to arrive at meaningful conclusions before establishing a safety in toto to biological systems and the environment. 

If there is no choice in using pesticides in agriculture, there is also no choice about adequate monitoring of all of our foodstuffs or about setting valid tolerances for pesticides on foods. We cannot afford even one mistake which involves all or most of the population. 

The Pure Food Law of 1906 was amended in 1938 to include pesticides on foods, primarily the arsenicals, such as lead arsenate and Paris green. It also required the adding of color to white insecticides, including sodium fluoride and lead arsenate, to prevent their accidental use as flour or other look-alike cooking materials. This was the first federal effort toward protecting the consumer from pesticide-contaminated food by providing tolerances for pesticide residues, namely arsenic and lead, in foods where these materials were necessary for the production of a food supply. 

By 1990, risk assessment had been used for more than 20 years to establish allowable residues of pesticides on food to assess the dangers of living near toxic waste sites to determine acceptable levels of air and water pollution to decide how to prioritize expenditures on environment-related government programs, and on and on. 

Many other risk factors are only expressed in individuals who are chronic smokers or suffer from alcoholism. These are serious issues that must be addressed and may be relevant to certain drugs and chemicals. However, they are not likely to be relevant to the issue of isolated exposure to residue levels of different pesticides on food as would occur when one eats a diet of produce obtained from the local grocer. It is a mistake to confuse them. 

EPA establishes raw agricultural commodity (RAC) and food additive tolerances for pesticides on food. Carcinogenic pesticides may be registered and tolerances may be set for the raw agricultural commodity if the levels are safe however, if the concentration of a pesticide on food increases when it is processed, a food additive tolerance is required. The Delaney clause of FFDCA does not allow a food additive tolerance to be set, even if EPA believes it is safe, if the compound has been shown to induce cancer in man or animal. A narrow interpretation of the Delaney clause has prevented registration of new products in circumstances where the upper-bound risks were estimated to be much less than one in a million. 

The regulation of carcinogenic pesticides on foods depends upon how EPA interprets and applies FIFRA, FFDCA Sections 408 and 409, and especially the Delaney clause in the FFDCA. Pesticide registrations are granted or denied under the FIFRA risk-benefit standard. However, food use pesticides cannot be registered, unless a tolerance or an exemption from a tolerance for the RAC was also granted under Section 408 of the FFDCA. 

Internationally recognized food standards, i.e.. Codex standards, have been established for more than three decades as standards for facilitating international trade and solving trade disputes. One of the many standards established by Codex is the maximum residue limit (MRLs) for pesticides on food commodities in international trade. Codex MRLs are used as national standards by many countries however, some countries continue to establish their own MRLs or tolerances and impose zero tolerance to residues of pesticides on imported crops which do not have nationally/regionally agreed-upon MRLs. Therefore, the acceptance of Codex MRLs among countries is different. An example of the variation in MRLs for carbaryl in some commodities is shown in Table 1. 

Residues of pesticides on food commodities also are regulated by EPA although the statutory basis on this control stems from the Federal Food, Drug, and Cosmetic Act (most of which is administered by the Food and Drug Administration). Because the use of pesticides on crops often leads to human consumption of food residues, a complex regulatory mechanism has evolved to determine residue levels that may be presumed safe for such consumption. These levels, termed tolerances, are defined after consideration of chronic feeding studies in laboratory animals and of analytical data, to determine what levels may follow from approved agricultural practices and a presumed daily intake of the toxicant by humans. 

The group of tests that must be performed for each pesticide depends on how that pesticide is to be used. For example, if a pesticide is not used on food or feed crops, extensive residue and metaboHsm tests in plants and domestic animals might not be required. Similarly, if a pesticide is not used in field crops nor on other extensive outdoor areas, aH the environmental fate studies might not be required. 

Subdivision O guidelines for residue chemistry data were originally pubHshed by the EPA in 1982. These have been supplemented to improve the rate of acceptance by EPA reviewers of the many reports submitted by registrants in support of tolerances for pesticides in foods. The residue chemistry studies most frequently rejected include metaboHsm in plants, food processing (qv) studies, and studies on storage stabHity of residues in field samples (57). AH tolerances (maximum residue levels) estabHshed under FIFRA are Hsted in 40 CFR under Sections 180 for individual pesticides in/on raw agricultural commodities, 180 for exemptions from tolerances, 185 for processed foods, and 186 for animal feeds. 

When illegal residues have been found in monitoring studies conducted by the FDA or USD A, the reason has often been that no U.S. tolerance had been requested for that particular pesticide in that specific crop. For example, an imported crop would be deemed to be adulterated and would be seized at the port of entry into the United States if found to contain a pesticide residue in the absence of a tolerance in that crop. This is so even if tolerances have been set for the same pesticide in several crops grown in the United States and the pesticide had been used to control a pest that does not exist in the United States. Furthermore, an international maximum residue level (MRL) might already have been estabUshed for that pesticide—crop combination under the Codex system of standards for food of importance in international trade. The U.S. GAO issued two reports on food safety and pesticides in 1991 (89,90). 

Regulating Pesticides in Food The De/anej Paradox, Report of Board on Agriculture, Committee on Scientific and Regulatory Issues Underlying Pesticide Use Patterns and Agricultural Innovation, U.S. National Research Council, National Academy Press, Washington, D.C., 1987, 272 pp. 

Problems that rank relatively high in duee of the four typos, or at least medium in all four, include criteria air pollutiuits, stratospheric ozone depletion, pesticide residues on food, and other pesticide risks (runoff and air deposition of pesticides)... 

From this analysis it is clear that in addition to their benefits, the use of pesticides in food production not only causes serious public health problems but also considerable damage to vital agricultural and natural ecosystems in the United States and world. A conservative estimate suggests that the environmental and social costs of pesticide use in the United States total about 4 billion each year. Worldwide the yearly environmental and public health costs are probably at least 100 billion. This is several times the 18 bllllon/yr spent on pesticides in the world. 

Children are likely to be exposed to methyl parathion in the same ways as adults, mainly by eating foods or drinking milk or water that contain residues of this chemical. Because of their smaller weight, children s intake of methyl parathion per kilogram of body weight may be greater than that of adults. The FDA and EPA permit residues of pesticides to be present in crops used as food, and these amounts are considered to be safe. The EPA, however, has recently used stricter regulations and has canceled the use of methyl parathion on food crops... 

Endosulfan is a manufactured pesticide. It is used to control a number of insects on food crops such as grains, tea, fruits, and vegetables and on nonfood crops such as tobacco and cotton. It is also used as a wood preservative. 

The MRL for pesticide residues is the maximum concentration of a pesticide residue (expressed milligrams per kilogram) legally permitted in or on food commodities and... 

The FQPA is another important statute for regulating pesticides. The FQPA amendments to FIFRA changed the way ERA regulates pesticides. The requirements included a new safety standard - reasonable certainty of no harm - which must be applied to all pesticides used on foods. ... 

For example, in order to meet the demanding requirements of legislation such as the European Union (EU) Baby Food Directive (Directive 95/5/EC and subsequent revisions), analysts must improve on the scope and sensitivity of multiresidue methods of analysis. This Baby Food Directive, which became effective on 1 July 2002, limits residues of all pesticides to a maximum level of 0.01 mgkg There will also be a banned list of pesticides, annexed to the Directive, which will not permit the use of certain pesticides on crops intended for use in baby food production. As a consequence, food manufacturers often require residue results for raw or primary ingredients within 24 8 h of sample receipt at the laboratory. 

Oxime carbamates are generally applied either directly to the tilled soil or sprayed on crops. One of the advantages of oxime carbamates is their short persistence on plants. They are readily degraded into their metabolites shortly after application. However, some of these metabolites have insecticidal properties even more potent than those of the parent compound. For example, the oxidative product of aldicarb is aldicarb sulfoxide, which is observed to be 10-20 times more active as a cholinesterase inhibitor than aldicarb. Other oxime carbamates (e.g., methomyl) have degradates which show no insecticidal activity, have low to negligible ecotoxicity and mammalian toxicity relative to the parent, and are normally nondetectable in crops. Therefore, the residue definition may include the parent oxime carbamate (e.g., methomyl) or parent and metabolites (e.g., aldicarb and its sulfoxide and sulfone metabolites). The tolerance or maximum residue limit (MRL) of pesticides on any food commodity is based on the highest residue concentration detected on mature crops at harvest or the LOQ of the method submitted for enforcement purposes if no detectable residues are found. For example, the tolerances of methomyl in US food commodities range from 0.1 to 6 mg kg for food items and up to 40 mg kg for feed items. ... 

It may be estimated conservatively that less than 10% of the food we eat is contaminated with harmful spray residues. These observations, correlated with the relatively low amounts of various pesticide residues found on food crops and the immeasurable trace that may be on a single service of the food, emphasize the little danger to health from spray residues. 

The wide publicity given DDT and the many new pesticides that have been developed during the past few years has made the public aware of the widespread use of spray chemicals. Many misstatements about the poisonous properties of these new products have caused abnormal concern and fear over the possible presence of excessive amounts of spray residues on food crops. This concern is a natural one, because the public does not realize the very small amount of the insecticidal residue that may remain on a single service of food, which usually does not exceed 0.25 pound in weight. Nor does the public realize that only a relatively small percentage of the food we eat has ever been treated with a spray or dust of a specific pesticide. 

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