Mortality of Aircraft Maintenance Workers Exposed to Trichloroethylene and Other Hydrocarbons and Chemicals: Extended Follow-Up

Global Outcomes Research Department, Merck and Co, Inc, NJ 08889, USA.
Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine (Impact Factor: 1.63). 12/2008; 50(11):1306-19. DOI: 10.1097/JOM.0b013e3181845f7f
Source: PubMed


To extend follow-up of 14,455 workers from 1990 to 2000, and evaluate mortality risk from exposure to trichloroethylene (TCE) and other chemicals.
Multivariable Cox models were used to estimate relative risk (RR) for exposed versus unexposed workers based on previously developed exposure surrogates.
Among TCE-exposed workers, there was no statistically significant increased risk of all-cause mortality (RR = 1.04) or death from all cancers (RR = 1.03). Exposure-response gradients for TCE were relatively flat and did not materially change since 1990. Statistically significant excesses were found for several chemical exposure subgroups and causes and were generally consistent with the previous follow-up.
Patterns of mortality have not changed substantially since 1990. Although positive associations with several cancers were observed, and are consistent with the published literature, interpretation is limited due to the small numbers of events for specific exposures.

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    • "Twenty-four studies in which there was a high likelihood of TCE exposure in individual study subjects (e.g., based on job-exposure matrices or biomarker monitoring) and which were judged to have met, to a sufficient degree, the standards of epidemiologic design and analysis were identified in a systematic review of the epidemiologic literature. Of the 15 of these 24 studies reporting the risk of kidney cancer (Zhao et al., 2005; Charbotel et al., 2006; Radican et al., 2008; Moore et al., 2010), most estimated Relative Risks (RRs) between 1.1 and 1.9 for overall exposure to TCE. Six of these 15 studies reported statistically significantly increased risks for either overall exposure to TCE (Brüning et al., 2003; Moore et al., 2010; Raaschou-Nielsen et al., 2003) or for one of the highest TCE exposure groups (Raaschou-Nielsen et al., 2003; Zhao et al., 2005; Charbotel et al., 2006; Moore et al., 2010). "
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