Objective: The present report updates the mortality cohort study of "Eternit" workers in Casale Monferrato, one of the major plant for the production of corrugated and plain sheets, tubes and high-pressure pipes in asbestos-cement in Italy active between 1907-1986.
Design: Retrospective cohort study.
Setting: The cohort included 3,443 blue-collar workers (2,663 men and 780 women) active between 1950 and 1986. Nine subjects had been excluded because of incomplete data. The follow-up ended in 2003. Mortality in the cohort was compared to the cause-specific rates for age and period of the Piedmont population and the SMR values were calculated for the period 1965-2003.
Main outcome: Analysis of cause-specific mortality.
Results: Follow-up was completed for 99.0% of the subjects. At the end of follow-up, 42% of the subjects were alive, 57% deceased and 1% lost to follow-up or moved abroad. In both sexes, a statistically significant increase of morality for all causes (men: SMR 135.1; 1,438 obs vs 1,064.1 exp; p < 0.01; women: RSM 149.5; 371 obs vs 248.2 exp; p < 0.01) was observed. The SMRs for lung, pleural and peritoneal cancer and for asbestosis increased according to duration of exposure and latency. For pleural cancer, increasing risks at shorter latencies were observed as exposure length increased. In men, the increase in the SMRs for lung and pleural cancer was reduced in the category of longest latency; still increased but declining SMRs were also observed at longer time since first exposure. Mortality from peritoneal cancer and asbestosis on the contrary increased with latency and with time since last exposure. Among women, a significant increase of mortality for uterine cancer (SMR 2569; 15 obs vs 5.8 exp; p < 0.01), ovarian cancer (SMR 227.3; 9 obs vs 4.0 exp; p < 0.05) and rectum cancer (SMR 318.6; 9 obs vs 2.8 exp; p < 0.01) was observed.
Conclusion: a significant increase in mortality from the main asbestos-related diseases was confirmed by duration of exposure. In relation to latency The SMRs for lung and pleural cancer present a curvilinear trend with a decrease for longest latency periods (after 30 years from the cessation of exposure). The SMRs for peritoneal cancer and asbestosis showed a monotonic increase.