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The Use of Data on Cholinesterase Inhibition for Risk Assessments of Organophosphorous and Carbamate Pesticides

This revised science policy emphasizes the weighing of all relevant evidence when selecting endpoints for the hazard assessment of anticholinesterase pesticides. This "weight-of-the-evidence" review, conducted on a case-by-case, chemical-by-chemical basis, is accomplished by performing an integrative analysis after assessing all the individual lines of evidence (including all available data on cholinesterase inhibition in all compartments -- central nervous system, peripheral nervous system, red blood cells, and plasma -- as well as data on clinical signs, symptoms and other physiological or behavioral effects). 

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