Associations between several sites of cancer and occupational exposure to benzene, toluene, xylene, and styrene: results of a case-control study in Montreal.
BACKGROUND
Except for the leukemogenic effects of benzene, there is inadequate or sparse evidence on the carcinogenicity of the most common monocyclic aromatic hydrocarbons. The purpose of this study was to generate hypotheses on associations between exposure to benzene, toluene, xylene, and styrene and various common types of cancer.


METHODS
In the context of a population-based case-control study carried out in Montreal, 3,730 cancer patients (15 types of cancers, not including leukemia) and 533 population controls were interviewed, and their job histories were translated by a team of experts into occupational exposures, including benzene, toluene, xylene, and styrene. In the present analysis, exposure to these substances was compared between each case series and a control group pooling selected cancer patients and population controls, using logistic regression analysis.


RESULTS
Exposure levels were low for most exposed subjects, and there was a high correlation between exposure to benzene, toluene and xylene. For most sites of cancer there was no evidence of excess risk due to these substances. However, limited evidence of increased risk was found for the following associations: esophagus-toluene, colon-xylene, rectum-toluene, rectum-xylene and rectum-styrene.


CONCLUSIONS
These latter observations warrant further investigation.
Gérin
M
M
Départment de médecine du travail et d'hygiène du milieu, Université de Montréal, Québec, Canada.
Siemiatycki
J
J
Désy
M
M
Krewski
D
D
D000328:Adult; D000368:Aged; D001554:Benzene / Q000009:adverse effects; D016022:Case-Control Studies; D016001:Confidence Intervals; D006801:Humans; D006841:Hydrocarbons, Aromatic / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000139:chemically induced* / Q000453:epidemiology; D009784:Occupational Diseases / Q000139:chemically induced* / Q000453:epidemiology; D016273:Occupational Exposure / Q000009:adverse effects; D016017:Odds Ratio; D011792:Quebec / Q000453:epidemiology; D012307:Risk Factors; D020058:Styrene; D013343:Styrenes / Q000009:adverse effects; D011795:Surveys and Questionnaires; D014050:Toluene / Q000009:adverse effects; D014992:Xylenes / Q000009:adverse effects
D006841:Hydrocarbons, Aromatic; D013343:Styrenes; D014992:Xylenes; D014050:Toluene; D020058:Styrene; D001554:Benzene