Environmental radon exposure and breast cancer risk in the Nurses’ Health Study II

Abstract

BackgroundRadon and its decay products, a source of ionizing radiation, are primarily inhaled and can deliver a radiation dose to breast tissue, where they may continue to decay and emit DNA damage-inducing particles. Few studies have examined the relationship between radon and breast cancer.MethodsThe Nurses’ Health Study II (NHSII) includes U.S. female registered nurses who completed biennial questionnaires since 1989. Self-reported breast cancer was confirmed from medical records. County-level radon exposures were linked with geocoded residential addresses updated throughout follow-up. Time-varying Cox regression models adjusted for established breast cancer risk factors were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).ResultsFrom 1989 to 2013, 3966 invasive breast cancer cases occurred among 112,639 participants. Increasing radon exposure was not associated with breast cancer risk overall (adjusted HR comparing highest to lowest quintile = 1.06, 95% CI: 0.94, 1.21, p for trend = 0.30). However, women in the highest quintile of exposure (≥74.9 Bq/m3) had a suggested elevated risk of ER−/PR- breast cancer compared to women in the lowest quintile (<27.0 Bq/m3) (adjusted HR = 1.38, 95% CI: 0.97, 1.96, p for trend = 0.05). No association was observed for ER+/PR+ breast cancer.ConclusionsAlthough we did not find an association between radon exposure and risk of overall or ER+/PR+ breast cancer, we observed a suggestive association with risk of ER−/PR- breast cancer.Electronic supplementary materialThe online version of this article (10.1186/s12940-017-0305-6) contains supplementary material, which is available to authorized users.

Cancer health disparities in racial/ethnic minorities in the United States

“…For example, AA/Bs and Hispanics/Latinos in the USA are more likely to live in low-income areas that are exposed to higher levels of environmental pollution. [64][65][66][67][68][69] Independent of SES, individuals from racial/ethnic minorities might be exposed to socio-environmental conditions and stressors that affect health outcomes throughout the course of life. For example, structural and interpersonal racism can translate to a higher risk of psychosocial stressors.…”

“…128 In addition, AA/Bs and Hispanics/Latinas are more likely to live in low-income areas with higher exposures to environmental pollution, and emerging epidemiology evidence supports a possible role for hazardous air pollutants, traffic emissions and radon in breast cancer, particularly HRbreast cancer. 64,65 The specific factors contributing to the higher prevalence of HER2 + breast cancer in Asians and Hispanics/Latinas are unknown. However, a study reporting a positive association between the proportion of Indigenous American ancestry and HER2 status in breast cancer patients from Peru, Colombia and Mexico suggested that germline genetic variants associated with this component of ancestry might play a role.…”

A Geologically Based Indoor‐Radon Potential Map of Kentucky

“…Among never smokers, exposure to radon may be more harmful for those exposed to secondhand smoke (Lagarde et al, 2001). Recent studies have also suggested relationships between radon exposure and both breast cancer risk and malignant melanoma, or skin cancer, mortality (Vienneau, 2017; VoPham et al, 2017). Despite these statistics, few homeowners are aware of the combined environmental risk of exposure to both tobacco smoke and radon.…”

Association of cancer screening and residing in a coal-polluted East Asian region with overall survival of lung cancer patients: a retrospective cohort study

“…A shared frailty random effects model may account for the regional heterogeneity in survival data 28 . After separating the cohort into subcohorts of patients diagnosed by screening or not, we used shared frailty models to examine for the presence of significant frailty term for covariates.…”