Extended Mortality Follow-up of a Cohort of 25,460 Workers Exposed to Acrylonitrile
Menée aux Etats-Unis auprès de 25 460 employés dans huit installations de production d'acrylonitrile (durée de suivi : 1 023 922 personnes-années), cette étude analyse l'association entre l'exposition professionnelle à l'acrylonitrile et la mortalité par cancer ou toutes causes confondues (8 124 décès)
We extended the mortality follow-up of a cohort of 25,460 workers employed at eight acrylonitrile (AN)-producing facilities in the United States by 21 years. Based on 8,124 deaths and 1,023,922 person-years of follow-up, we evaluated the relationship between occupational AN exposure and mortality. Standardized mortality ratios (SMR) based on deaths through December 31, 2011 were calculated. Work histories and monitoring data were used to develop quantitative estimates of AN exposure. Hazard ratios (HR) were estimated by Cox proportional hazards regression. All-cause mortality and mortality from total cancer were less than expected compared with the U.S. population. We observed an excess of death due to mesothelioma (SMR=2.24,95%CI:1.39, 3.42); no other SMRs were elevated overall. Cox regression analyses revealed an elevated risk of lung and bronchial cancer (N=808 deaths), with an HR>12.1 ppm-year vs Unexposed=1.43 (95%CI:1.13-1.81, p-trend=0.05), lagged 10-yrs, that was robust in sensitivity analyses adjusting for smoking and co-exposures including asbestos. Mortality from bladder cancer (HR, lagged 10 years>2.56 ppm vs Unexposed=2.96 (95%CI:1.38-6.34,p-trend=0.02) and pneumonitis (HR>3.12 ppm-year vs Unexposed=4.73 (95%CI:1.42-15.76,p-trend=0.007) was also associated with AN exposure. This study provides additional evidence of an association between AN exposure and lung cancer, as well as possible increased mortality from bladder cancer and pneumonitis.