Screening for insecticide overexposure under field conditions: a reevaluation of the tintometric cholinesterase kit.
Am J Publ Health 1994 Mar; 84(3):479-481
The validity of a semiquantitative screening kit for measuring whole blood cholinesterase levels in persons exposed to organophosphate pesticides was evaluated. Blood was drawn from 79 male workers for analysis of both whole blood cholinesterase via the tintometric kit and erythrocyte cholinesterase via a reference assay. The workers were employed at rural landing strips and a large crop dusting airport in Nicaragua, and were considered to be highly exposed to organophosphate pesticides. While overall correlation between the kit and the reference assay was good, either sensitivity or specificity of the tintometric kit was less than 75% for each of the three critical tintometric categories commonly used to define the limit of normal (75%, 62.5%, and 50% of control activity). The tintometric tests proved to have a predictive value, either positive or negative, of less than 80%. The authors conclude that caution should be used in interpreting results of this biomarker of organophosphate exposure, particularly in the screening of populations with low prevalence of overexposure; accuracy may be compromised without appropriate validation and rigorous quality control measures.
NIOSH-Publication; NIOSH-Grant; Neurotoxic-effects; Occupational-exposure; Screening-methods; Biological-monitoring; Agricultural-chemicals; Cholinesterase-inhibitors; Organo-phosphorus-pesticides; Humans;
Rob McConnell, MD, Division of Occupational and Environmental Medicine, Box 1057, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029
American Journal of Public Health
Mount Sinai School of Medicine, New York, New York