Mortality Among Titanium Dioxide Workers at Three DuPont Plants

Objective: To evaluate the mortality among workers employed at three titanium dioxide plants in the United States. Methods: We expanded and updated a cohort employed at titanium dioxide plants. Cause-specific standardized mortality ratios (SMRs) were calculated combined and stratified by plant for workers employed at least 6 months between 1935 and 2005. Results: No indications of excess mortality from any cause were found. All causes SMR increased with length of plant operation as did most cause-specific SMRs. With lung, the target organ of interest, no increases in malignant or nonmalignant respiratory disease were observed. Conclusions: The mortality rates are comparable with the general US population. Increasing SMRs with length of plant operation is indicative of waning healthy worker effect with time since first employment. The results are comparable with other titanium dioxide cohort studies.