Mortality among workers exposed to acrylonitrile in fiber production: an update.

OBJECTIVE: The investigation updates the mortality experience through 2002 for a cohort of workers exposed to acrylonitrile (AN). METHODS: Standardized mortality ratios (SMR) were estimated based on two reference populations: the US population and a regional employee population. Exposure-response analyses were conducted using Cox regression models for cumulative and mean intensity exposure measures. RESULTS: In the cohort of 2548 workers, 839 deaths have occurred with 91 deaths due to respiratory system cancer. Most standardized mortality ratio estimates are at or near no-effects levels. Hazard ratio (HR) estimates indicate no increased mortality risk for respiratory system cancer (adjusted HR = 0.96, 95% confidence interval: 0.74, 1.25). CONCLUSIONS: In summary, no mortality outcome of a priori interest, principally respiratory system cancer, is associated with increased AN exposure among fiber production workers over five decades of follow-up.