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Objective: To evaluate the mortality for an occupational cohort and discuss its suitability as an internal comparison population., Methods: The study included 114,683 employees who worked at 1 of 25 US locations between January 1, 1960, and December 31, 2005. Standardized mortality ratios (SMRs) and 95% confidence intervals (CIs) were calculated based on US rates., Results: The SMRs were significantly favorable for all causes, malignant neoplasms, heart disease, and external causes. The most common cancer sites were lung in men (SMR = 83, 95% CI = 80 to 86), and breast in women (SMR = 94, 95% CI = 80 to 111)., Conclusions: Overall, the mortality rates were favorable and robust. Discussed within are topics of historical concern at specific locations that may influence the cohort's appropriateness for future studies.

Objective: We examined the overall mortality rates of 1599 workers employed between 1969 and 1988 at a New Zealand site, which manufactured trichlorophenol., Methods: We developed exposure estimates for 2,3,7,8-tetrachlorodibenzo-p-dioxin from a serum dioxin evaluation and used standardized mortality ratios (SMR) and proportional hazards models to evaluate risk from exposure., Results: Among exposed workers, deaths from total cancers (SMR = 1.1, 95% confidence intervals [CI]: 0.9-1.4), non-Hodgkin lymphoma (SMR = 1.6, 95% CI: 03-4.7), and ischemic heart disease (SMR = 1.1, 95% CI: 0.9-1.5) were slightly greater than expected, whereas deaths from lung cancer (SMR = 0.8, 95% CI: 0.4-1.5) were less than expected. We observed no significant trends with exposure levels., Conclusions: Although this study is small, we found no increasing trend of cancer or disease risk with increasing 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure with the possible exception of all cancers combined.

We observed 42,076 men and 11,706 women first employed at the Michigan locations of The Dow Chemical Company between 1940 and 1994. Follow-up was 98% complete, and we identified 16,242 deaths. Significant deficits in standardized mortality ratios were observed for all causes, all malignant neoplasms, and more than a dozen other causes of death when compared with rates in the United States. We observed significant elevations for several causes of death among employees of a magnesium foundry. There is little modern exposure information, because the foundry was sold nearly 40 years ago. This routine surveillance activity provided a generally favorable overview of the health experience of our employees and did not suggest a need for an additional focused study.

A longitudinal comparison of 305 toluene diisocyanate (TDI) and 581 hydrocarbons workers employed at a Texas chemical manufacturing facility from 1971 through 1997 tested whether workplace exposure to TDI was associated with changes in any of the respiratory measures collected by the company's health surveillance program. Mean TDI exposures measured 96.9 ppb-months, or 2.3 ppb per job. At the end of the study, there were no differences in self-reported symptoms between the groups. Longitudinal analyses of symptoms and pulmonary function showed no correlation with TDI exposure, yielding an average annual decrease in forced expiratory volume at 1 second of 30 mL per year. We concluded that exposure to TDI at workplace concentrations was not associated with respiratory illnesses in this cohort, and consistent with other recent research, it seemed not to accelerate the normal age-related decline in pulmonary function.

Obesity has been identified as a risk factor for liver disease in a number of cross-sectional studies. We investigated the association of biochemical livers tests (BLTs) among male employees of The Dow Chemical Company who had participated in two consecutive health surveillance examinations. The activity of three liver enzymes-alanine aminotransferase, aspartate aminotransferase, and gamma glutamyl transferase were used as measures of liver injury. Body mass index was strongly associated with increased enzyme activity in both examinations. Alcohol consumption was similarly associated with higher BLT results. Body mass index remained significantly associated with each BLT after controlling for alcohol consumption, race, and age. When changes in BLTs were investigated over time, the employees who gained weight showed a significant increase in alanine aminotransferase activity compared with those who did not gain weight.