title: Workplace exposure to diesel and gasoline engine exhausts and the risk of colorectal cancer in Canadian men.
abstract: BACKGROUND
  The International Agency for Research on Cancer (IARC) classified diesel exhaust as carcinogenic to humans (Group 1) and gasoline exhaust as a possible carcinogen (Group 2B) based studies of lung cancer, however the evidence for other sites is limited. We addressed this question by investigating exposure to diesel and gasoline emissions with respect to risk of colorectal cancer in men.
  
  
  METHODS
  We used data from a population-based case-control study with incident cases of colon (n = 931) and rectal (n = 840) cancer and 1360 controls from 7 Canadian provinces conducted in 1994-1997. Lifetime occupational history and information on other risk factors was collected. Occupational hygienists, blinded to case-control status, assigned exposures to each job for 3 dimensions: concentration, frequency, and reliability. Logistic regression was used to estimate odds ratios (OR) and their 95 % confidence intervals (CI), adjusted for age, province, use of proxy respondents, smoking, body-mass index, physical activity, intake of alcohol, processed meats, and occupational exposure to asbestos and aromatic amines.
  
  
  RESULTS
  Among CRC cases, 638 (36 %) were exposed to diesel and 814 (46 %) were exposed to gasoline emissions. Relative to the unexposed, elevated risks were observed among subjects ever exposed to high concentration levels of diesel emissions for colorectal cancer (OR = 1.65, 95 % CI = 0.98-2.80) and rectal cancer (OR = 1.98, 95 % CI = 1.09-3.60), but not colon cancer. Prolonged (>10 years) exposure at high concentrations was also associated with high risks of rectal cancer (OR = 2.33 95 % CI = 0.94-5.78; p-trend = 0.02). No statistically significant associations were observed for gasoline emissions.
  
  
  CONCLUSIONS
  Our findings suggest that sustained high-level exposure diesel emissions may increase the risk of rectal cancer.
authors.affiliation: Dalla Lana School of Public Health, University of Toronto, 155 College Street, 6th Floor, Toronto, ON, M5T 3 M7, Canada. linda.kachuri@mail.utoronto.ca.|Occupational Cancer Research Centre, Cancer Care Ontario, 525 University Avenue, 3rd Floor, Toronto, ON, M5G 2 L3, Canada. linda.kachuri@mail.utoronto.ca.|Prevention and Cancer Control, Cancer Care Ontario, 620 University Ave, Toronto, ON, M5G 2 L7, Canada. linda.kachuri@mail.utoronto.ca.
authors.forename: Linda
authors.initials: L
authors.lastname: Kachuri
authors.affiliation: Dalla Lana School of Public Health, University of Toronto, 155 College Street, 6th Floor, Toronto, ON, M5T 3 M7, Canada. Paul.villeneuve@carleton.ca.|Occupational Cancer Research Centre, Cancer Care Ontario, 525 University Avenue, 3rd Floor, Toronto, ON, M5G 2 L3, Canada. Paul.villeneuve@carleton.ca.|CHAIM Research Centre, Carleton University, 5435 Herzberg Laboratories, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada. Paul.villeneuve@carleton.ca.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Villeneuve
authors.affiliation: INRS-Institut Armand-Frappier, Institut national de la recherche scientifique, University of Quebec, 531 boul. des Prairies, Édifice 12, Laval, QC, H7V 1B7, Canada. Marie-Elise.Parent@iaf.inrs.ca.
authors.forename: Marie-Élise
authors.initials: MÉ
authors.lastname: Parent
authors.affiliation: Department of Epidemiology and Community Medicine, University of Ottawa, 451 Smyth Rd, Ottawa, ON, K1H 8 M5, Canada. ken47johnson@gmail.com.
authors.forename: Kenneth C
authors.initials: KC
authors.lastname: Johnson
authors.affiliation: Dalla Lana School of Public Health, University of Toronto, 155 College Street, 6th Floor, Toronto, ON, M5T 3 M7, Canada. Shelley.Harris@cancercare.on.ca.|Occupational Cancer Research Centre, Cancer Care Ontario, 525 University Avenue, 3rd Floor, Toronto, ON, M5G 2 L3, Canada. Shelley.Harris@cancercare.on.ca.|Prevention and Cancer Control, Cancer Care Ontario, 620 University Ave, Toronto, ON, M5G 2 L7, Canada. Shelley.Harris@cancercare.on.ca.
authors.forename: Shelley A
authors.initials: SA
authors.lastname: Harris
mesh_terms: D000368:Aged; D000395:Air Pollutants, Occupational / Q000633:toxicity*; D000397:Air Pollution / Q000706:statistics & numerical data; D002170:Canada; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D005260:Female; D005742:Gasoline / Q000633:toxicity*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018986:Motor Vehicles; D009784:Occupational Diseases / Q000139:chemically induced* / Q000453:epidemiology; D016273:Occupational Exposure / Q000706:statistics & numerical data*; D018570:Risk Assessment; D012307:Risk Factors; D001335:Vehicle Emissions / Q000633:toxicity*
chemical_list: D000395:Air Pollutants, Occupational; D005742:Gasoline; D001335:Vehicle Emissions