Objectives: The aim of this study was to assess cancer incidence in a cohort of woodworkers exposed to softwood dust in a Lithuanian wooden joinery products factory.
Methods: The study population consisted of 1518 workers (1080 men and 438 women) employed in the factory for at least 1 year between 1947 and 1996 and living in Lithuania on 1 January 1978, when the follow-up for cancer incidence began. The follow-up period for cancer was 1978-2007. Cancer risk was assessed by standardised incidence ratios (SIR) with reference to the national population.
Results: Overall cancer incidence was not increased among woodworkers. However, the number of mouth and pharynx cancer cases among male woodworkers was significantly increased compared with expected numbers (SIR 2.19, 95% CI 1.17 to 3.74). A higher risk was found for cancer of the buccal cavity than for pharyngeal cancer (SIRs 2.83 and 1.45, respectively). The SIR for larynx cancer was also elevated (SIR 1.39, 95% CI 0.64 to 2.64) among men, while the number of lung cancer cases was higher than expected only among women (SIR 2.07, 95% CI 00.57 to 5.31).
Conclusions: This results of this study support the hypothesis that exposure to softwood dust may increase the risk of oral and pharyngeal cancer. No support was found for an increased risk of other respiratory cancers among workers exposed to softwood dust.