Article

Silicosis and lung cancer among workers in North Carolina dusty trades

National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, USA.
Scandinavian Journal of Work, Environment & Health (Impact Factor: 3.1). 02/1995; 21 Suppl 2:81-3.
Source: PubMed

ABSTRACT In 1940-1983, 760 cases of silicosis were identified among male North Carolina (NC) workers in dusty trades. Vital status was ascertained through 1983 for 714 silicotics, and death certificates were obtained for 546 of the 550 decedents. The standardized mortality ratio (SMR) for lung cancer based on United States rates was 2.6 [95% confidence interval (95% CI) 1.8-3.6] for whites, 2.3 (95% CI 1.5-3.4) for whites unexposed to other known occupational carcinogens, and 2.4 (95% CI 1.5-3.6) for whites with no other exposure and diagnosed with silicosis while still employed in dusty trades. In addition, the age- and smoking-adjusted rate for silicotics was 3.9 times higher (95% CI 2.4-6.4) than that of nonsilicotic metal miners. This analysis effectively controlled for confounding by age, cigarette smoking, exposure to other occupational carcinogens, and detection bias. The results congrue with the hypothesis of an association between silicosis and lung cancer.

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    • "Of the two case register studies quoted, that of N. Carolina dusty trades workers (Amandus et al., 1995, 1991, 1992) seems to us to be the stronger, though not flawless since misdiagnosis was frequent, and the representativeness of the study population is not established. The Finnish study does not inform the reader about the reliability of the diagnosis of silicosis (Partanen et al., 1994; Kurppa et al., 1986). "
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