The Diesel Exhaust in Miners Study: A Cohort Mortality Study With Emphasis on Lung Cancer

ERS Inc, Morgantown, WV, USA.
Journal of the National Cancer Institute (Impact Factor: 12.58). 03/2012; 104(11):869-83. DOI: 10.1093/jnci/djs035
Source: PubMed

ABSTRACT Current information points to an association between diesel exhaust exposure and lung cancer and other mortality outcomes, but uncertainties remain.
We undertook a cohort mortality study of 12 315 workers exposed to diesel exhaust at eight US non-metal mining facilities. Historical measurements and surrogate exposure data, along with study industrial hygiene measurements, were used to derive retrospective quantitative estimates of respirable elemental carbon (REC) exposure for each worker. Standardized mortality ratios and internally adjusted Cox proportional hazard models were used to evaluate REC exposure-associated risk. Analyses were both unlagged and lagged to exclude recent exposure such as that occurring in the 15 years directly before the date of death.
Standardized mortality ratios for lung cancer (1.26, 95% confidence interval [CI] = 1.09 to 1.44), esophageal cancer (1.83, 95% CI = 1.16 to 2.75), and pneumoconiosis (12.20, 95% CI = 6.82 to 20.12) were elevated in the complete cohort compared with state-based mortality rates, but all-cause, bladder cancer, heart disease, and chronic obstructive pulmonary disease mortality were not. Differences in risk by worker location (ever-underground vs surface only) initially obscured a positive diesel exhaust exposure-response relationship with lung cancer in the complete cohort, although it became apparent after adjustment for worker location. The hazard ratios (HRs) for lung cancer mortality increased with increasing 15-year lagged cumulative REC exposure for ever-underground workers with 5 or more years of tenure to a maximum in the 640 to less than 1280 μg/m(3)-y category compared with the reference category (0 to <20 μg/m(3)-y; 30 deaths compared with eight deaths of the total of 93; HR = 5.01, 95% CI = 1.97 to 12.76) but declined at higher exposures. Average REC intensity hazard ratios rose to a plateau around 32 μg/m(3). Elevated hazard ratios and evidence of exposure-response were also seen for surface workers. The association between diesel exhaust exposure and lung cancer risk remained after inclusion of other work-related potentially confounding exposures in the models and were robust to alternative approaches to exposure derivation.
The study findings provide further evidence that exposure to diesel exhaust increases risk of mortality from lung cancer and have important public health implications.

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Available from: Aaron Blair, Sep 28, 2015
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    • "The motivation to monitor black carbon and other nonvolatile particle compounds in atmospheric networks involves , on the one hand, the necessity to help quantify the regional and global effect of light absorption (Cheng et al., 2009; Koch et al., 2009; Stier et al., 2007; Bond and Bergstrom, 2006). On the other hand, atmospheric soot particles and non-volatile compounds have been associated with certain adverse health effects by epidemiological and toxicological studies (Attfield et al., 2012; Janssen et al., 2012; Mazzarella et al., 2007; Totlandsdal et al., 2012). A monitoring strategy such as that pursued in GUAN attempts to provide experimental data that can be used to address both issues mentioned above. "
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    Atmospheric Chemistry and Physics 09/2014; 14(18-18):10145-10162. DOI:10.5194/acp-14-10145-2014 · 5.05 Impact Factor
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    • "The International Agency for Research on Cancer has labeled diesel exhaust as a human carcinogen (Benbrahim-Tallaa et al., 2012), while the National Institute for Occupational Safety and Health (NIOSH, 1988) has identified DPM as a potential occupational carcinogen (NIOSH, 2012). A recently published NIOSH study reported that heavy exposure of non-metal miners to diesel exhaust increased their risk of death from lung cancer (Attfield et al., 2012) and the National Cancer Institute (NCI) has shown additional evidence of lung cancer mortality risk (Silverman et al., 2012). "
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