Cancer incidence of sulfite pulp workers in Denmark

Objectives: Studies have indicated an excess risk of stomach cancer, pancreas cancer, and non-Hodgkin's lymphoma for sulfite pulp mill workers, and therefore cancer incidence was evaluated for 2 Danish sulfite mills. Methods: Altogether 2238 workers employed in 1955-1990 were included in a historic cohort and followed until 31 December 1993. National cancer rates were used to calculate the expected number of cancer cases. Results: The overall cancer risk was close to the expected, the standardized incidence ratio (SIR) being 1.01. The risk of stomach cancer was doubled [10 observed, SIR 1.99, 95% confidence interval (95% CI) 0.95-3.66], as was the risk of pancreatic cancer (7 observed, SIR 1.88, 95% CI 0.75-3.88). For the men with known pulp exposure, lung cancer was slightly increased (SIR 1.53, 95% CI 0.94-2.37). Other cancers with elevated risks were leukemia (7 observed, SIR 1.84) and soft-tissue sarcomas (4 observed, SIR 2.37). The risk of non Hodgkin's lymphoma was not increased. Conclusions: The excess risk of stomach cancer and pancreatic cancer found in this study was in accordance with that of other studies from sulfite pulp mills.