Regional variation in the incidence of symptomatic pesticide exposures: Applications of geographic information systems

Objective: To evaluate the epidemiology of symptomatic human pesticide exposures using poison control center data and geographic information systems. Methods: All symptomatic human pesticide exposures reported to the poison center during the period from January 1 to December 31, 2000 were included for analysis using geographic information systems. A space-time scan statistic was utilized to evaluate for clustering of symptomatic human exposures. Results: Of 322 symptomatic pesticide exposures, 297 (92%) contained spatial identifiers that could be further analyzed using geographic information systems. A spatial and temporal cluster of symptomatic pesticide exposures was identified during the period from April 1 to August 31, 2000, covering a large geographic area of eastern and predominantly rural regions of the state. The relative risk of reporting a symptomatic pesticide exposure among individuals living within this geographic area was 1.8 (log likelihood ratio = 18.5, P = 0.0005). Conclusions: Geographic information systems can be effectively utilized by poison control centers to study regional and temporal variation in the incidence of human pesticide exposures. With the collection of more specific spatial identifiers, geographic information systems may have many additional applications in the surveillance and prevention of pesticide and other sentinel event exposures.