Effects of organophosphate insecticide residue variability on reentry intervals

Am J Ind Med. 1990;18(3):313-9. doi: 10.1002/ajim.4700180312.


A stochastic simulation program was written to study the importance of residue variability in predicting excessive chronic (seasonal) cholinesterase (AChE) inhibition and acute illness among a cohort of agricultural harvesters grouped into crews exposed to AChE-inhibiting insecticides. It was concluded that residue variability can substantially affect the cohort's AChE level only for daily mean AChE inhibitions below 4% per day, increasing end-of-season mean AChE inhibition but actually decreasing the cohort's end-of-season variability. The incidence of acute individual and group (crew) AChE inhibitions in excess of that potentially producing clinical symptoms (assumed herein to be greater than 50% in a day), exhibits a fairly clear boundary as a function of a combination of the residue's mean and deviation. The predicted acute response accurately parallelled reported rates, thus validating the simulation model.

MeSH terms

  • Agricultural Workers' Diseases / chemically induced
  • Agricultural Workers' Diseases / enzymology*
  • Cholinesterase Inhibitors / poisoning*
  • Computer Simulation
  • Humans
  • Insecticides / poisoning*
  • Models, Biological
  • Organophosphorus Compounds*
  • Pesticide Residues / poisoning*
  • Seasons
  • Stochastic Processes
  • Time Factors


  • Cholinesterase Inhibitors
  • Insecticides
  • Organophosphorus Compounds
  • Pesticide Residues