Applications pesticide residues, exposure

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. 

Among the first dermal dosimeters used in exposure research were 4 x 4-in cellulose or gauze patches which were pinned to the outer and inner surfaces of clothing or vests which farm workers would wear during the application or re-entry phase of the smdy. These patches were easy to manufacture and when pinned to the shirt or pants of the worker made for an easily used dosimeter pad. The major advantage to the use of the patch to estimate worker exposure was this method s ability to differentiate the relative contributions of pesticide residues to different parts of the worker s body. This sampling technique in turn could lead to recommendations (i.e., the use of... 

This document deals only with estimating exposure to direct additives and chemical contaminants. The procedures used to estimate exposure to chemical contaminants in food (including naturally occurring toxicants, such as mycotoxins) are essentially the same as those used for direct additives. Thus, contaminants will be considered in the discussion of direct additive exposure estimation. The procedures discussed herein are equally applicable to color additives, GRAS substances, prior-sanctioned ingredients, and pesticide residues. 

The many worst-case assumptions built into cancer risk assessments are there because of policy decisions, not because of scientific ones, and they confuse attempts to allocate money effectively for public health. For example, EPA estimates of synthetic pesticide residues in the diet have used the theoretical maximum human residue that is anticipated under the most severe field application conditions, which is often a large overestimate compared to the measured residues in food. Despite the EPA s estimated high risks from exposures to several pesticides, the U.S. Food and Drug Administration detected no residues of those pesticides in the food samples in its Total Diet Study.59... 

Nash RG, Kearney PC, Maitlen JC, 5ell CR, Fertig 5N. Agricultural applicators exposure to 2, 4-Dichlorophenoxyacetic acid. In Pesticide residues and exposure. Plimmer JR, editor. AC5 symposium series 182,1982, Chap 10 119-132. 

Occupational exposure to maneb and mancozeb can occur by the inhalation or dermal routes during the formulation and spray application of these pesticides (HSDB 1999). The general populahon is unlikely to be exposed to excess levels of pesticide residues on food, since crops analyzed for these compounds were found to have either non-detectable levels of the compounds or levels within allowable limits (Okumura et al. 1991) (see Section 5.4.4). 

As pesticides in agriculture and horticulture, which may result in exposure through accidental contamination during their manufacture and in-use applications nr incidental exposures through eating residues in treated crops (see Chapter 39). 

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