Mortality among maintenance employees potentially exposed to asbestos in a refinery and petrochemical plant

Abstract

This paper reports the mortality experience from 1948 to 1989 of 2,504 maintenance employees who had a minimum of one year of employment in jobs with potential exposure to asbestos at a Texas refinery and petrochemical plant. For the purposes of this study, “potential exposure” is equated with those jobs or crafts having the greatest direct potential proximity to, or which worked directly with, asbestos‐containing materials, especially asbestos‐containing thermal insulation. Approximately one‐half of the study population had 10 years or longer potential exposure, and 80% had their first potential exposure before 1970. The total population exhibited significantly lower mortality for all causes, the standardized mortality ratio (SMR = 77); and for all cancer (SMR = 85), as compared to residents in the surrounding communities. Statistically significant deficits in mortality were also observed in a number of noncancerous diseases such as heart disease (SMR = 78; 95% CI = 69‐88), nonmalignant respiratory disease (SMR = 70; 95% CI = 50‐95), and cirrhosis of the liver (SMR = 44; 95% CI = 22‐79). Mortality among employees who had 20 years or longer since their first potential exposure was also examined; the pattern of mortality was similar to that exhibited by the total cohort, with a slight increase in the SMR for most of the causes. The only statistically significant excess of mortality found was a fourfold increase in mesothelioma (5 observed and 1.2 expected deaths); the SMR was 428 (95% CI = 139‐996) for the total cohort and was 469 (95% CI = 152‐1093) for those who had 20 years or more since first potential exposure. In contrast to asbestos industry worker studies, mortality for lung cancer was substantially lower than the general population (SMR = 81; 95% CI = 63‐103). The observed number of deaths for cancer of the larynx was virtually the same as expected (3 observed vs. 2.8 expected). This study also showed decreased mortality for cancers of gastrointestinal organs such as the esophagus (SMR = 78), stomach (SMR = 63), large intestine (SMR = 91), rectum (SMR = 55), or pancreas (SMR = 90)—cancers that have been reported to be elevated in studies of various industry workers directly exposed to asbestos. © 1996 Wiley‐Liss, Inc.

A 56-Year Mortality Follow-Up of Texas Petroleum Refinery and Chemical Employees, 1948–2003

“…A more detailed description of maintenance work at this facility has been reported previously. 40 The overall mortality in the maintenance subgroup was favorable compared to that of the population of Harris County. Cancer mortality was 8% to 10% lower, which was borderline significant.…”

Malignant pleural mesothelioma in US automotive mechanics: Reported vs expected number of cases from 1975 to 2007

“…Similarly, the case presented in Dodson et al (2000) worked as a shipyard insulator from 1941-1944, while the case described in Kolonel et al (1985) worked in a shipyard for at least 24 years (Dodson et al, 2000;Kolonel et al, 1985). One of the cases described in Tsai et al (1996) (Case #4) also worked as a boilermaker for two years from 1945-1947(Tsai et al, 1996. Boilermakers and boilermaker mechanics make, install, repair, and repipe steel fabrications, such as boilers, closed vats, and other large heating or pressure vessels.…”

Mesothelioma and lung tumors attributable to asbestos among petroleum workers

“…In this re®nery, among personnel classi®ed as maintenance workers (357 subjects, 9,548 person±years), ®ve pleural mesotheliomas were observed, yielding a highly increased mortality risk after comparison with both local (SMR 5.47; 95% CI 1.78±12.76) and national (SMR 29.27; 95% CI 9.51± 68.31) reference populations. A statistically signi®cant excess of lung tumor deaths (N 16) was also detected Gennaro et al [1991a] 4.8 5 Christie et al [1991] 3.9 a 3 Schnatter et al [1992] 5.7 7 Hornstra [1993, unpublished] 4.0 16 Gennaro et al [1994] 2.7^16.6 b 10 Honda et al [1995] 2.0 a^3 .2 c 9 Finkelstein [1996] 24.4 d 6 Tsai et al [1996a] 2.2 a 7 Tsai et al [1996b] 4.3 5 a Not statistically significant at P`0.05. Local and Nationalreference,respectively.…”