Abstract
We have previously shown an elevated risk of lung cancer mortality in diesel exhaust exposed railroad workers. To reduce exposure misclassification, we obtained extensive historical information on diesel locomotives used by each railroad. Starting in 1945, we calculated the rate each railroad converted from steam to diesel, creating annual railroad-specific weighting factors for the probability of diesel exposure. We also estimated the average annual exposure intensity based on emission factors. The U.S. Railroad Retirement Board provided railroad assignment and work histories for 52,812 workers hired between 1939–1949, for whom we ascertained mortality from 1959–1996. Among workers hired after 1945, as diesel locomotives were introduced, the relative risk of lung cancer for any exposure was 1.77 (95% CI = 1.50–2.09), and there was evidence of an exposure–response relationship with exposure duration. Exposed workers hired before 1945 had a relative risk of 1.30 (95% CI = 1.19–1.43) for any exposure and there was no evidence of a dose response with duration. There was no evidence of increasing risk using estimated measures of intensity although the overall lung cancer risk remained elevated. In conclusion, although precise historical estimates of exposure are not available, weighting factors helped better define the exposure–response relationship of diesel exhaust with lung cancer mortality.
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References
Office of Environmental Health Hazard Assessment (1998) Health risk assessment for diesel exhaust. California Environmental Protection Agency, Sacramento, CA
Office of Research and Development (2002) Health assessment document for diesel engine exhaust. Washington, DC: National Center for Environmental Assessment, US Environmental Protection Agency; 01 May 2002. Report No. USEPA EPA/600/8-90/057F
IARC (1989) Monographs on the evaluation of carcinogenic risks to humans. Volume 46. Diesel and gasoline engine exhausts and some nitroarenes. IARC, Lyon
National Toxicology Program (2002) Report on carcinogens, 10th edn. US Department of Health and Human Services, Public Health Service 2002, December 2002
Garshick E, Laden F, Hart JE, et al (2004) Lung cancer in railroad workers exposed to diesel exhaust. Environ Health Perspect 112(15):1539–1543
US Department of Labor Bureau of Labor Statistics (1972) Railroad technology and manpower in the 1970s. Washington, DC: USGPO, 1972. Report No. Bulletin 1717
Woskie SR, Smith TJ, Hammond SK, Schenker MB, Garshick E, Speizer FE (1988) Estimation of the diesel exhaust exposures of railroad workers: II. National and historical exposures. Am J Ind Med 13(3):395–404
Woskie SR, Smith TJ, Hammond SK, Schenker MB, Garshick E, Speizer FE (1988) Estimation of the diesel exhaust exposures of railroad workers: I. Current exposures. Am J Ind Med 13(3):381–394
US EPA Office of Air and Radiation, US EPA Office of Air Quality Planning and Standards (1996) Compilation of Air Pollution Emission Factors. Volume 1. Stationary Point and Area Sources. Washington, DC: US EPA
Bhatia R, Lopipero P, Smith AH (1998) Diesel exhaust exposure and lung cancer. Epidemiology 9(1):84–91
Lipsett M, Campleman S (1999) Occupational exposure to diesel exhaust and lung cancer: a meta-analysis. Am J Public Health 89(7):1009–1017
Dockery DW, Pope ACd, Xu X, et al (1993) An association between air pollution and mortality in six U.S. cities. N Engl J Med 329(24):1753–1759
Pope CA III, Thun MJ, Namboodiri MM, et al (1995) Particulate air pollution as a predictor of mortality in a prospective study of U.S. adults. Am J Respir Crit Care Med 151(3 Pt 1):669–674
Nyberg F, Gustavsson P, Jarup L, et al (2000) Urban air pollution and lung cancer in Stockholm. Epidemiology 11(5):487–495
Liukonen LR, Grogan JL, Myers W (2002) Diesel particulate matter exposure to railroad train crews. AIHA J (Fairfax, Va) 63(5):610–616
Verma DK, Finkelstein JN (2002) Cancer risk from diesel exhaust exposure in the Canadian railroad industry: a feasibility study. In: Diesel Epidemiology Working Group (eds) Research directions for improve estimates of human exposure and risk from diesel exhaust. Health Effects Institute, Boston, MA
Verma DK, Finkelstein MM, Kurtz L, Smolynec K, Eyre S (2003) Diesel exhaust exposure in the Canadian railroad work environment. Appl Occup Environ Hyg 18(1):25–34
Finkelstein M, Verma D (2002) Cancer risk from diesel exhaust exposure in the Canadian railroad industry: a feasibility studyfin. In: Diesel Epidemiology Working Group (eds) Research directions for improve estimates of human exposure and risk from diesel exhaust. Health Effects Institute, Boston, MA
Office of Mobile Sources and Office of Air Quality Planning and Standards (1992) Procedures for emission inventory preparation, Volume IV: Mobile sources. Washington, DC, US EPA. Report No. PB92–209386INZ
Lorang P (1991) Locomotive emission factors for inventory guidance document. In Ann Arbor, MI
Acknowledgments
Supported by NIOSH CCR115818 and NCI CA79725. The authors thank Hongshu Guan for programming assistance, and the Railroad Retirement Board, in particular, Eileen Binkus and Anne Alden.
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An erratum to this article is available at http://dx.doi.org/10.1007/s10552-006-9020-2.
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Laden, F., Hart, J.E., Eschenroeder, A. et al. Historical estimation of diesel exhaust exposure in a cohort study of U.S. railroad workers and lung cancer. Cancer Causes Control 17, 911–919 (2006). https://doi.org/10.1007/s10552-006-0027-5
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DOI: https://doi.org/10.1007/s10552-006-0027-5