RESUMEN
During the period 1979-1982, serum cholinesterase levels were determined in blood samples collectedfrom workers employed at the Insect Vector Control Division, Trinidad, W.I. A total of 1,162 blood samples were collected, of which 116 showed suppressed cholinesterase levels. Those workers with low serum cholinesterase levels included 46 residual spraymen, 66 Aedes aegypti operators and 4 controls. The difference in number of spraymen and Aedes operations with low cholinesterase levels was significant (p<.001). No significant differences were found in the number of Aedes operators with low cholinesterase levels from North and South Trinidad. Similarly, no differences were found in the number of residual spraymen from North and South Trinidad with low cholinesterase levels. A total of 7 Aedes operators and 4 residual spraymen had persistently low serum cholinesterase levels. It is likely that the main areas of absorption were the hands and forearms, with further absorption occurin via respiration. The need for continuous monitoring and supervision of vector contro workers who handle insecticides is stressed