Pesticide residues reduction

In 1990, the National Research Council Committee on National Monitoring of Human Tissues reviewed and evaluated the uses and effectiveness of NHMP (NRC 1991). In its review, the committee noted that NHATS was effective in documenting a widespread and significant prevalence of pesticide residues in the general population and showed that reductions in use of PCBs, DDT, and dieldrin have been followed by a decline in measured concentrations of these compounds (NRC 1991). The committee s review of the program, with its discussion of the need for improved monitoring, was the impetus for the development of NHEXAS. 

The latter example points out the potential of the technique as a screening method for the identification of toxic organometallic compounds, for example, in pesticide residue analysis. With an initial screening of total Sn by ICP-MS in a survey on cyhexatin (an organotin acaricide), a limited number of suspect fruit samples (three out of 72) were identified and then submitted to confirmatory analysis with a GC-MS method [85]. This approach resulted in a 30 percent reduction of the survey cost in terms of staff hours. 

It may come to mind that the introduction of crops that impact pesticide use will inevitably lead to shifts in pesticide residue patterns in foods derived from these crops. In insect-resistant crops, for example, reductions in insecticide sprays against the target insects can be anticipated and concomitant reductions in crop residues. For herbicide toler-... 

Davies, J. E., Edmundson, W. F., Maceo, A., Irvin, G. L. Cassady, J. and A. Barquet. 1971. Reduction of pesticide residues in human adipose tissue with diphenylhydantoin. Eood Cos-met. Toxicol, 9 413-23. 

Data relative to the effect of greenhouse structure on airborne and surface pesticide residues and the reduction of the exposure potential due to the use of protective clothing and equipment and... 

Knowledge of the basic physico-chemical properties of pesticides, methods of their appUcation, their fate in the environment and especiaUy in food chains, along with information on their changes during storage and processing of food materials and products, is an essential prerequisite for successful adherence to legislative measures and the related reduction of the risk of exposure of consumers to possible pesticide residues. 

Information on the effects that cause an increase or decrease in levels of pesticide residues in food raw materials and the final products are very important, because in estimating health risks from dietary exposure to residues of pesticides, it is necessary to consider the form in which the given food is consumed. In most cases, technological and culinary processes lead to a reduction, and often to the complete removal, of pesticide residues. 

Removal of surface layers may, in crops such as bananas, pineapples, kiwi, citruses, melons and others, result in a marked reduction in the levels of non-systemic pesticide residues applied directly to the crop... 

Most of the technological processes used in fruit and vegetable processing include washing and blanching. The decrease in the levels of pesticide residues is possible particularly in the case of pesticides that are soluble in water, or in the case of contact pesticides deposited on the plant surface that can be mechanically removed. The overall effects resulting in a reduction of pesticide residues depend on a number of factors, the most important of which are ... 

Reduction of aromatic nitro groups occurs in three steps, via nitroso and hydroxylamine intermediates, to the amine. The amine can go on to form polymeric residues by a mechanism analogous to that for oxidative coupling of phenols, as in Equation 2. Abiotic nitro reduction is well documented for pesticides that contain aromatic nitro groups, such as the phosphorothioate esters methyl and ethyl parathion (22, 30-33). 

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