%0 Journal Article
%T Ambient polycyclic aromatic hydrocarbon exposure and breast cancer risk in a population-based Canadian case-control study.
%A Hinton P
%A Villeneuve PJ
%A Galarneau E
%A Larsen K
%A Wen D
%A Meng J
%A Savic-Jovcic V
%A Zhang J
%A King WD
%J Cancer Causes Control
%V 0
%N 0
%D 2024 Apr 17
%M 38630334
%F 2.532
%R 10.1007/s10552-024-01866-4
%X <B>OBJECTIVE: </B>Polycyclic aromatic hydrocarbons (PAHs) represent a class of ubiquitous pollutants recognized as established human carcinogens and endocrine-disrupting chemicals. PAHs have seldom been modeled at the population-level in epidemiological studies. Fluoranthene is a prevalent PAH in urban settings and correlates with the occurrence of other PAHs. The purpose of this study was to evaluate associations between long-term residential exposure to ambient PAHs and breast cancer risk, both pre- and post-menopausal, in Canada.<BR><B>METHODS: </B>Using the National Enhanced Cancer Surveillance System (NECSS), a national-scale Canadian population-based case-control study, annual fluoranthene exposures were estimated using the GEM-MACH-PAH chemical transport model on the basis of geocoded residential histories throughout a 20-year exposure window. Odds ratios (ORs) and 95% confidence intervals (CIs) controlling for potential confounders were estimated using logistic regression. Separate analyses were conducted for Ontario and national samples given a finer-resolution exposure surface and additional risk factor information available for Ontario.<BR><B>RESULTS: </B>Positive associations were observed between fluoranthene exposure and premenopausal breast cancer, with inconsistent findings for postmenopausal breast cancer. For premenopausal breast cancer, adjusted ORs of 2.48 (95% CI: 1.29, 4.77) and 1.59 (95% CI: 1.11, 2.29) were observed when comparing the second highest category of exposure to the lowest, among the Ontario and national samples, respectively. For postmenopausal breast cancer, adjusted ORs were 1.10 (95% CI: 0.67, 1.80) and 1.33 (95% CI: 1.02, 1.73). Associations for the highest level of exposure, across both samples and menopausal strata, were non-significant.<BR><B>CONCLUSIONS: </B>This study provides support for the hypothesis that ambient PAH exposures increase the risk of premenopausal breast cancer.