Organophosphate pesticides, measuring exposure

Davies JE, Peterson JC. 1997. Surveillance of occupational, accidental, and incidental exposure to organophosphate pesticides using urine alkyl phosphate and phenolic metabolite measurements. Aim NY Acad Sci 837 257-268. 

Disulfoton and its breakdown products can be measured in the blood, urine, feces, liver, kidney, or body fat of exposed people. In cases of occupational or accidental exposure to disulfoton, the breakdown products are often measured in the urine. The breakdown products are relatively specific for disulfoton and a few other similar organophosphate pesticides and can be detected in urine for up to one week after people were last exposed. Because disulfoton inhibits cholinesterase in blood and in blood cells, inhibition of this enzyme activity may also suggest exposure to disulfoton. Cholinesterase activity in blood and in blood cells may remain inhibited for as long as 1-2 weeks after the last exposure. Because other organophosphate pesticides also inhibit cholinesterase activity in blood and blood cells, this test is not specific for disulfoton. The measurement of cholinesterase in blood and blood cells and the amount of disulfoton breakdown products in the urine cannot always predict how much disulfoton you were exposed to. Your doctor can send samples of your blood or urine to special laboratories that perform these tests. Chapters 2 and 6 provide more information about medical tests. 

Exposure to organophosphate pesticides is often measured by determination of alkyl phosphate or phenol metabolites in the urine. Determination of blood cholinesterase activity can be a valuable indicator of exposure if pre-exposure cholinesterase activity is known (3, 5). Since normal cholinesterase levels... 

C.P. Weisskopf and J.N. Seiber, New approaches to the analysis of organophosphate metabolites in the urine of field workers, in ACS Symposium Series Biological Monitoring for Pesticide Exposure Measurement, Estimation, and Risk Reduction, eds. R.G.M. Wang, C.A. Franklin, R.C. Honeycutt, and J.C. Reinert, American Chemical Society, Washington, DC, pp. 206-214 (1989). 

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