Pesticide residues sources

Pesticides, including insecticides, herbicides, and fungicides, are widely used in agriculture, and the potential for these residues to accumulate in food has led to concern for human safety. Pesticide residues may enter food animals from environmental sources or from treated or contaminated feeds. Immunoassay development for pesticides has had major impacts for pesticide registrations, analysis of residues in foods, monitoring environmental contamination, determination of occupational exposure, and integration of pest management. 

Char from a variety of sources, including coal, is used to produce activated carbon. The two most important uses for activated carbon are for water and wastewater treatment and decolorization. Other uses for activated carbon include the capture of pollutants such as volatile organic compounds (VOCs) and pesticide residues from industrial waste streams. 

Mirex was not detected in 27,065 samples of food collected in 10 state food laboratories from 1988 and 1989 (Minyard and Roberts 1991). Mirex was also not detected in domestically produced or imported foods sampled as part of the FDA Pesticide Residue Monitoring Study during 1988-1989 (FDA 1990), was detected (at less than 1 % occurrence) in foods sampled in 1989-1990 (FDA 1991), and was not detected in foods sampled in 1990-1991 and 1992-1992 (FDA 1992, 1993). Mirex residues were detected in one sample of 806 composited milk samples collected through the Pasteurized Milk Program by the EPA in 1990-1991 (Trotter and Dickerson 1993). The milk was sampled at 63 stations that provide an estimated 80% of the milk delivered to U.S. population centers. At each station, milk from selected sources was composited to represent milk routinely consumed in the station s metropolitan area. The detection of mirex occurred in milk samples from Cristobal, Panama. 

The inclusion of an estimate of all potential sources of human exposure and not just pesticide residues in food. 

The UK has taken advantage of the power of retailers (in particular supermarkets) in dictating to their suppliers (and therefore ultimately the producers) by releasing the names of retail outlets from where samples were sourced for its pesticide residues surveillance scheme (MAFF, 1999). A media furore met the first report of the UK s Working Party on Pesticide Residues to name and shame retail outlets. Indeed the Guardian, a major UK newspaper, featured a leaked version of the report on its front page the day before the planned release. As a result of this there was significant interest in a problem with chlormequat in pears. The supermarkets took a particular interest in the... 

Table 10.1. Pesticide residue levels in water samples from main rivers in Thailand, 1985-1988 (Source Thapinta and Hudak, 2000)...

Some aspects of the sources, occurrence, and dispersion of airborne pesticide residues (6, 27) and methods for their sampling and analysis (28, 29, 30, 31) have been reviewed elsewhere. In this paper, the focus will be on sampling methodology, experimental design, and some results from recent field tests aimed at determining the entry and proximate fate of airborne residues in relation to specific agricultural treatments. 

The environmental protection agencies of most countries have identified agriculture as the largest nonpoint source of surface water pollution. This is a major problem in each country. Pesticides and nitrates from fertilizers are detected in the groundwater in many agricultural regions. Soil erosion is a concern in many countries. Pest resistance to pesticides continues to grow, and the problem of pesticide residues in food has yet to be resolved. All nations are more competitive in international markets than a few years ago. 

Turner, B. Powell, S. Miller, N. Melvin, J. A Field Study of Fog and Dry Deposition as Sources of Inadvertent Pesticide Residues on Row Crops Report of the Environmental Hazard Assessment Program California Department of Food and Agriculture Sacramento, CA, November 1989. 

A critical pesticide residue problem today is that of chlorinated hydro-carbon pesticides in milk. The easiest solution to this problem is an across-the-board restriction on the use of chlorinated hydrocarbon pesticides in any environment which might contaminate dairy animals or feeds. This type of restriction would doubtless create hardships on other agricultural enterprises in those areas and may in fact be unnecessary. Detailed examination of the possible sources may well point to solutions which will not sweepingly encompass all chlorinated hydrocarbon insecticides or all uses of them. 

Directly from farms we source most of our milk requirements, part of our coffee needs and most of the fruit and vegetable we need for the production of baby food. The latter are most difficult to find in the open market, because a certain percentage of these fruits and vegetables have pesticide residues above 10 ppb. These residues are in almost all cases within the legal limits for common food products and without any health risk. However, for our needs it would be too costly, too risky and logistically not feasible to test all raw materials before we could release them for the production of baby food. 

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