SOFT-TISSUE SARCOMA AND NON-HODGKINS-LYMPHOMA IN WORKERS EXPOSED TO PHENOXY HERBICIDES, CHLOROPHENOLS, AND DIOXINS - 2 NESTED CASE-CONTROL STUDIES

We examined the effect of exposure to chemicals present in the product ion and spraying of phenoxy herbicides or chlorophenols in two nested case-control studies of soft tissue sarcoma and non-Hodgkin's lymphoma . Eleven sarcoma and 32 lymphoma cases occurring within an internation al cohere were matched for age, sex, and country of residence with 55 and 158 controls, respectively. Exposures to 21 chemicals or mixtures were estimated by three industrial hygienists who were blind to the su bject's case-control status. Excess risk of soft tissue sarcoma was as sociated with exposure to any phenoxy herbicide [odds ratio (OR) = 10. 3; 95% confidence interval (CI) 1.2-91] and to each of the three major classes of phenoxy herbicides (2,4-dichlorophenoxyacetic acid, 2,4,5- trichlorophenoxyacetic acid, and 4-chloro-2-methylphenoxyacetic acid), to any polychlorinated dibenzodioxin or furan (OR = 5.6; 95% CI = 1.1 -28), and to 2,3,7,8-tetrachlorodibenzo-p-dioxin (OR = 5.2; 95% CI = 0 .85-32). Sarcoma risk was not associated with exposure to raw material s or other process chemicals. In the non-Hodgkin's lymphoma study, ass ociations were generally weaker than those found in the study on sarco ma. These findings indicate that workers exposed to phenoxy herbicides and their contaminants are at a higher risk of soft tissue sarcoma.