Occupational wood dust exposure and the risk of laryngeal cancer: a population based case-control study in Germany.

BACKGROUND: To investigate the effect of exposure to wood dust on the risk of laryngeal cancer.

METHODS: A population-based case-control study on laryngeal cancer was conducted in South-West Germany between 1st of May 1998 to 31st of December 2000 with 257 histologically confirmed cases (236 males, 21 females), age 37 to 80 years, and 769 population controls (702 males, 67 females), 1:3 frequency matched by age and sex. Occupational exposures and other risk factors were obtained with face-to-face interviews using a detailed standardized questionnaire. The complete individual work history was assessed. Work conditions were obtained by job-specific questionnaires for selected jobs known to be associated with exposure to potential carcinogens. Additionally, a specific substance check-list was used as a method for exposure assessment.

RESULTS: 43 (16.7%) cases (41 males, 2 females) and 107 (13.9%) controls (105 males, 2 females) reported wood dust exposure. Numbers were almost identical for two different methods of exposure assessment; however, the agreement of these methods was around 95%. A strong effect on laryngeal cancer risk after adjustment for smoking, alcohol and education was observed for high exposure to hardwood dust (OR = 2.6, 95% CI 1.3-5.2) and to softwood dust (OR = 2.2, 95% CI 1.1-4.2), as assessed by substance list.

CONCLUSIONS: Our findings for higher exposure to hardwood and softwood dust contribute to the evidence that wood dust, in particular from hardwood is an independent risk factor.