COHORT MORTALITY AND NESTED CASE-CONTROL STUDY OF LUNG-CANCER AMONG STRUCTURAL PEST-CONTROL WORKERS IN FLORIDA (UNITED-STATES)

A previous report on the mortality of this cohort of Florida (United S tates) pest control workers found the risk of lung cancer was positive ly associated with the number of years licensed. An additional follow- up (1977-82) of this male cohort confirmed the excess (SMR = 1.4) and the rising risk with increasing number of years licensed (SMR = 2.2 am ong workers employed more than 20 years). A nested case-control study was undertaken to determine the effects of smoking and the type of pes ticide exposure on lung cancer risk. Occupational histories and other data were obtained on 65 deceased lung cancer cases, 122 deceased cont rols, and 172 living controls. Interviews were conducted with next-of- kin regardless of the vital status of the subject. Odds ratios (OR) we re adjusted by age and smoking. Adjustments for diet and other occupat ions had no effect on risk estimates and were not included in the fina l model. Using information from licensing records, ORs for lung cancer were greater for workers first licensed before age 40 (OR = 2.4, 95 p ercent confidence interval [CI] = 1.0-5.9 with deceased controls) and increased from 1.4 (CI = 0.7-3.0) for subjects licensed 10-19 years to 2.1 (CI = 0.8-5.5) for subjects licensed 20 or more years. Using livi ng controls, an association with duration of employment was observed w hen years of licensure were lagged five years, but was not observed in unlagged analyses. Using information from the questionnaire, the risk of lung cancer was greater among those who worked as pest control ope rators than non-pest control workers. Although numbers were typically small, lung cancer risk among pest control operators was associated wi th reported exposure to carbamates, organophosphates, and phenoxyaceti c acids and more specifically with diazinon, DDT, carbaryl, and pro-po xur. These results further suggest that pesticides may play a role in lung cancer risk and underscore the need for research that focuses on specific chemicals.