Soft tissue sarcoma risk in Swedish licensed pesticide applicators

Two Swedish studies have suggested that exposure to phenoxy acid herbicides may cause soft tissue sarcoma. This association has been subsequently investigated in a number of epidemiologic studies. Results are inconsistent. In this study the risk of soft tissue sarcoma in a cohort of 20,245 Swedish pesticide applicators, of whom 72% were estimated to have been exposed to phenoxy acid herbicides, was analyzed. The cohort was observed by means of the Swedish Cancer Register from date of license until Dec 31, 1984, or until death if it occurred prior to that date. The mean follow-up time was 13.9 years. Seven patients with soft tissue sarcoma were observed compared with 7.7 expected on the basis of the incidence in Sweden. The relative risk was found to be 0.9 (95% confidence interval, 0.4 to 1.9). This finding is consistent with the hypothesis that exposure of phenoxy acid herbicides does not increase risk of soft tissue sarcoma.