Elevated Cancer Mortality in a German Cohort of Bitumen Workers: Extended Follow-Up Through 2004

The mortality follow-up in a cohort of German asphalt workers covered an additional 6 years. Male workers (N = 7919) were classified into four exposure categories: (1) exposure to bitumen only, (2) to bitumen and coal tar, (3) neither to tar nor to bitumen, and (4) unknown exposure. Exposure-specific standardized mortality ratios (SMR) and associated 95% confidence intervals (CI) based on age- and calendar period-specific national mortality rates were calculated. To compare exposed and unexposed workers, relative risks were estimated by Poisson regression. By the end of 2004, 835 workers had died. The SMR for lung cancer was 1.77 (95% CI 1.46–2.16). Head and neck cancer showed an SMR of 2.36 (95% CI 1.78–3.07). Bladder cancer mortality was elevated threefold. Significantly elevated cancer-related SMRs were also found for all malignant tumors. In addition, elevated mortality rates of nonmalignant causes such as alcoholism, liver cirrhosis, and unnatural causes of deaths including accidents were observed. A...