Mortality Among a Large Cohort of Chemical Manufacturing Employees

Abstract

Cause-specific mortality was surveyed among 19,608 male employees with 1 or more years of service between 1940 and 1980 at the Texas Operations of Dow Chemical U.S.A. Vital status was ascertained through 1980 for 97.3% of the cohort members, and death certificates were obtained for 96.4% of the 3,444 decedents. Mortality risks were found to vary, depending upon which of 3 population groups (United States, Texas, and local counties) was used for comparison, although significantly fewer than expected deaths from all causes was a common finding due to significant deficits in diabetes, diseases of the circulatory system, and cirrhosis of the liver. Significantly more deaths were from ill-defined conditions and cancers of unspecified sites. Lung cancer was significantly elevated in comparisons with the incidences in the United States and Texas, but not in comparison with those in the local counties. The influence of age at hire, period of hire, duration of employment, interval since entry into cohort, employment status, and two measures of social class--educational level and job category--were explored with the use of the Mantel-Haenszel method as adapted for a cohort study. Findings from these analyses are discussed in relation to the observations of other investigators and in the context of the possible impact of these findings on future studies of this work force.

An updated mortality study of workers at a petroleum refinery in Beaumont, Texas

“…While the earlier study reported an elevated nonsignificant SMR of 145 (95%CI ϭ 90-222) for senility and ill-defined conditions among white males, the update showed a significant SMR of . This finding is consistent with elevations reported for this category in other industrial studies in this region of the United States and is explainable by local death certification practices [Bond et al, 1985;Olsen et al, 1994].…”

Mortality among workers engaged in the development or manufacture of styrene-based products--an update.

“…Six of the seven deaths in this category occurred among employees from the Texas facility. The state of Texas is known to have an abnormally high death rate from symptoms, senility and ill-defined conditions, and this regional phenomenon appears to be the most likely explanation for the finding in this cohort (6).…”

Half‐century of cause‐specific mortality experience of chemical manufacturing employees

“…The method of the study cohort identification has been reported in detail elsewhere [Bond et al, 1985b]. Briefly, all Texas Operations employees located in the Brazosport area (Freeport, Texas) who had 1 or more years of service since January 1 , 1940, were eligible for inclusion in a Texas Operations vital status registry.…”

“…The cohort has been updated periodically throughout the 1980s based on computerized company records. Besides the Freeport, Texas location (Plants A and B) that was studied in the original report by and Bond et al [1985b], the nearby Oyster Creek site of Texas Operations was also included in the present study. The historic census for Oyster Creek was determined by review of plant rosters, work history records, and computer personnel files.…”