目的:多环芳烃(PAHs)是一类普遍存在的污染物,被认为是已确定的人类致癌物和内分泌干扰化学物质。在流行病学研究中,很少在人群水平上对PAHs进行建模。氟蒽是城市环境中普遍存在的PAH,与其他PAH的发生有关。这项研究的目的是评估长期居住暴露于环境PAHs与乳腺癌风险之间的关联。绝经前和绝经后,在加拿大。
方法:使用国家增强癌症监测系统(NECSS),一项全国规模的加拿大基于人口的病例对照研究,使用GEM-MACH-PAH化学迁移模型,根据20年暴露窗口中地理编码的居住历史,估算了年度荧蒽暴露。使用逻辑回归估计控制潜在混杂因素的赔率比(OR)和95%置信区间(CI)。对安大略省和国家样本进行了单独分析,给出了更高分辨率的暴露表面和安大略省可用的其他风险因素信息。
结果:氟蒽暴露与绝经前乳腺癌呈正相关,与绝经后乳腺癌的发现不一致。对于绝经前乳腺癌,当比较第二高的接触类别与最低的接触类别时,观察到2.48(95%CI:1.29,4.77)和1.59(95%CI:1.11,2.29)的校正OR,在安大略省和国家样本中,分别。对于绝经后乳腺癌,校正OR分别为1.10(95%CI:0.67,1.80)和1.33(95%CI:1.02,1.73)。最高暴露水平的协会,在样本和更年期地层中,不重要。
结论:这项研究为环境PAH暴露增加绝经前乳腺癌风险的假设提供了支持。
OBJECTIVE: 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.
METHODS: 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.
RESULTS: 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.
CONCLUSIONS: This study provides support for the hypothesis that ambient PAH exposures increase the risk of premenopausal breast cancer.