Exposure to cement dust, related occupational groups and laryngeal cancer risk: results of a population based...

A population-based case-control study was performed in the Rhein-Neckar region, Germany, to evaluate occupational risk factors for the development of laryngeal cancer ("Rhein-Neckar-Larynx Study"). Between May 1998 and December 2000, 257 patients (236 males, 21 females), aged 37-80, with histologically confirmed laryngeal cancer, as well as 769 population control persons (702 males, 67 females), were included (1:3 frequency matched by age and sex). History of occupational exposures, as well as other risk factors (tobacco, alcohol), was obtained with face-to-face interviews using a detailed standardized questionnaire. The complete individual work history was assessed. A detailed assessment of work conditions was obtained by job-specific questionnaires (JSQs) for selected jobs known to be associated with exposure to potential laryngeal carcinogens. Estimates for total exposure hours by substance were calculated based on JSQs. Published occupational hygiene data were used to infer semiquantitative scores of exposure intensity for specific job tasks. After adjustment for tobacco and alcohol intake, a significant elevated odds ratios (OR) could be demonstrated for persons that were exposed to cement during their work as building and construction workers. An OR of 2.42 was calculated for workers of the high exposed subgroup (95% confidence interval: 1.14-5.15; p < 0.001). Smoking was the main confounding factor because the unadjusted cement OR of 3.20 dropped down to 2.42 after adjustment for tobacco intake. We conclude that there is good evidence for cement dust exposure acting as a tobacco, alcohol and asbestos independent risk factor for laryngeal carcinoma. Our study gives a base for further toxicologic investigations on this topic.