Exposure to road traffic and railway noise and postmenopausal breast cancer: A cohort study

Abstract

Exposure to traffic noise may result in stress and sleep disturbances. Studies on self-reported sleep duration and breast cancer risk have found inconsistent results. In a population-based Danish cohort of 29,875 women aged 50-64 years at enrolment in 1993-1997, we identified 1219 incident, postmenopausal breast cancer cases during follow-up through 2010. Mean follow-up time was 12.3 years. Road traffic and railway noise was calculated for all present and historical residential addresses from 1987 to 2010. We used Cox proportional hazard model for analyses and adjusted for hormone replacement therapy use, parity, alcohol consumption and other potential confounders. We found no overall association between residential road traffic or railway noise and breast cancer risk. Among women with estrogen receptor negative breast cancer, a 10-dB higher level of road traffic noise (continuous scale) during the previous 1, 5 and 10 years were associated with 28% (95% CI: 1.04-1.56), 23% (95% CI: 1.00-1.51) and 20% (95% CI: 0.97-1.48) higher risks of estrogen receptor negative breast cancer, respectively, in fully adjusted models. Similarly, a 10-dB increase in railway noise (1-year mean at diagnosis address) increased risk for estrogen receptor negative breast cancer by 38% (95% CI: 1.01-1.89). There was no association between road traffic or railway noise and estrogen receptor positive breast cancer. In conclusion, these results suggest that residential road traffic and railway noise may increase risk of estrogen receptor negative breast cancer. As the first study on traffic noise and breast cancer results should be treated with caution.

Breast cancer and exposure to aircraft, road, and railway-noise: a case–control study based on health insurance records

“…Regarding the observed risks due to road and rail traffic noise, modest increased risk estimates were also observed in the noise exposure categories >70 dB. In general, our findings corroborate the results reported by Sörensen et al (27) that ER-cancers appear to be more susceptible to environmental traffic noise exposure than ER+ cancers. Although the linear risks we observed for road and rail traffic noise exposure were lower than those reported for the Danish cohort, this may be due in part to the difference in exposure ranges considered.…”

“…However, the prevalence of ER+ cancers was lower than that reported by Sörensen et al (27) indicating a possible underreporting of ER+ cancers. This misclassification might be due in part by women first diagnosed towards the end of the observation period who had not yet received any ancillary treatment.…”

“…Although the linear risks we observed for road and rail traffic noise exposure were lower than those reported for the Danish cohort, this may be due in part to the difference in exposure ranges considered. Sörensen et al (27) considered 42 dB to be the background noise level and set traffic noise beneath this level to 42 dB, while we used 40 dB as the background noise level and set lower traffic noise values to 35 dB. Differences in results may also be due to the fact that Sörensen et al were able to better adjust for potential confounding factors, such as parity and examined only postmenopausal breast cancer risks.…”

“…Existing research regarding a possible increased cancer risk due to environmental traffic noise exposure is limited and inconclusive (25)(26)(27)(28). Visser and colleagues (28) first examined the incidence of cancer near the Amsterdam Schiphol airport by comparing the standardized incidence ratios (SIR) of residents living in a "core area" (defined by noise contours) exposed to increased aircraft noise and airport-related pollutants with the SIR for residents living in the less exposed surrounding areas.…”

“…In Denmark, Sörensen et al (27) examined the risk of breast cancer due to road and railway traffic noise exposure in a prospective study of postmenopausal women (aged 50-64 years) registered in the Danish Diet, Cancer and Health Cohort with ten years of exposure data. Although the incidence rate ratios (IRR) of all breast cancers were not related to increased traffic noise levels, stratified examination of ER status found the incidence of ER negative (ER-) cancers to be increased for each 10 dB increase in evening-night weighted (L den ) road [IRR 1.28, 95% confidence interval (CI) 1.04-1.56] and railway (IRR 1.38, 95% CI 1.01-1.89) traffic noise.…”