Retrospective cohort study of diesel exhaust exposure and lung cancer in US railroad workers: mortality update 1959-1996.
Garshick-E; Laden-F; Smith-TJ; Gagnon-D; Jackson-SL; Dockery-DW; Speizer-FE
Am J Respir Crit Care Med 2001 Apr; 163(5)(2)(Suppl):A718
RATIONALE: Studies of diesel exhaust exposure and lung cancer have been limited by a short duration of follow-up. Most US railroad diesel exhaust exposure started during the 1950's (95% diesel by 1959). Lung cancer mortality was previously assessed through 1976 in 55,407 US railroad workers aged 40-64 in 1959. Here we assess mortality through 1996. METHODS: The US Railroad Retirement Board (RRB) provided work history for 54,974 (99.2%) workers. Mortality was assessed using RRB, Social Security, and Health Care Financing Administration sources. Cause of death was obtained from death certificates and the National Death Index. Proportional hazard methods were used to assess mortality. Job code in 1959 was used as an exposure index since railroad jobs are stable. RESULTS: There were 43,600 deaths overall; 4,277 from lung cancer. Adjusting for age, workers aged 40-44 in a diesel exhaust exposed job in 1959 (workers with greatest duration of exposure) had an elevated relative risk (RR; 95%CI) of lung cancer mortality of 1.36 (1.19-1.55). Workers aged 45-49, 50-54,55-59 also had an elevated RR (1.23, 1.22, 1.32, respectively), whereas the RR in the oldest workers (60-64) was not elevated. Workers on operating trains had the greatest RR. CONCLUSIONS: Workers aged 40-59 in diesel exhaust exposed jobs in 1959 had an increased risk of dying of lung cancer. Although the age group with the longest exposures after 1959 had an elevated risk, risk was also elevated in other workers. Occupational exposures to diesel exhaust and other inhaled particles in the 1940's to 1960's may be contributors to lung cancer mortality in this cohort.
Respiratory-system-disorders; Lung-cancer; Lung-disorders; Diesel-emissions; Diesel-engines; Diesel-exhausts; Cancer; Carcinogens; Mortality-data; Mortality-rates; Railroad-industry; Exhaust-gases; Exposure-assessment; Exposure-levels; Age-factors
Work Environment and Workforce: Mixed Exposures
American Journal of Respiratory and Critical Care Medicine. Abstracts of the American Thoracic Society 2001 International Conference, May 18-23, 2001, San Francisco, California
Harvard Medical School, Boston, Massachusetts