Lung cancer case-control study of beryllium workers

Background Cohort mortality studies have found elevated lung cancer mortali ty among beryllium-exposed workers, but none evaluated the association betw een beryllium exposure level and lung cancer risk A nested case-control stu dy of lung cancer within a beryllium processing plant was conducted to inve stigate the relationship between level of beryllium exposure and lung cance r. Methods Lung cancer cases were identified by mortality follow-up through 19 92 of a cohort of male workers at a beryllium alloy production plant. Each of 142 lung cancer cases was age-race-matched to five controls. Calendar-ti me-specific beryllium exposure estimates were made for every job in the pla nt and were used to estimate workers' cumulative, average, and maximum expo sures. The potential confounding effects of smoking were also evaluated. Results Lung cancer cases had shorter tenures and lower lifetime cumulative beryllium exposures than controls, but higher average and maximum exposure s. However, after applying a 10- and 20-year lag, exposure metrics were hig her for cases. Odds ratios in analyses lagged 20 years were significantly e levated for those with higher exposure compared to the lowest exposure cate gory. Significant positive trends were seen with the log of the exposure me trics. Smoking did not appear to confound exposure-response analyses. Conclusion increased lung cancer among workers with higher bagged beryllium exposures and lack of evidence for confounding by cigarette smoking, provi de further evidence that beryllium is a human lung carcinogen. Am. J. Ind. Med. 39.133-144, 2001. Published 2001 Wiley-Liss, Inc.