Mortality surveillance of a US wide cohort of chemical industry workers.

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.

Mortality in workers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin at a trichlorophenol plant in New Zealand.

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.