Occupational exposure to chemicals and risk of thyroid cancer in Sweden

To explore thyroid cancer (TC) risk in the Swedish population, associated with occupational exposure to certain chemicals. National cancer and death registries were used to follow-up (1971-1989) all Swedish workers employed in the 1970 census. Each combination of occupation and industry was linked to a Swedish job-exposure matrix (JEM), with exposure to 13 chemicals classified as "possible exposure", "probable exposure" or "unexposed". Relative risks were obtained using Poisson models adjusted for age, period and geographical area. A second analysis was performed, in which adjustment was additionally made for simultaneous exposure to other matrix chemicals and ionising radiations. Probable exposure to solvents among women displayed an increased risk (RR = 1.91; 95%CI:1.05-3.45), mainly due to a higher risk observed among shoe-cutters, lasters and sewers engaged in shoe-making. Exposure to solvents, used mainly in the shoe and leather industry, seems to be associated with excess TC among women.