Mortality of steelworkers employed in hot jobs.

This paper investigates possible relationships between heat stress of steelworkers and cause-specific mortality patterns. Prior to field investigation, jobs were identified which appeared to involve heat stress exposure. A selected sample of these jobs was surveyed for assessing the workers' environmental and metabolic heat load. These data were utilized to form different categories of heat stress. Mortality patterns of workers in jobs falling in each of the heat stress categories were analyzed by length of exposure for those workers from a cohort of 59,000 steelworkers who held one of the surveyed jobs. The comparison group consisted of workers who never worked in any of the work areas in which job were surveyed but were members of the same cohort. Findings of interest are: a deficit in mortality from cardiovascular disease for workers in jobs involving higher levels of environmental heat exposure; a high risk of death from cardiovascular disease for workers with less than 6 months of exposure and a downward trend in mortality for workers who remained on the job, indicating a possible relationship between inability to work in jobs involving heat stress and health; and, increased risks of digestive disease mortality among workers exposed to higher levels of environmental heat.