Air pollution drives greater bone loss in postmenopausal women living in lower-income neighborhoods

Neighborhood socioeconomic conditions significantly amplify the effect of air pollution on bone health in postmenopausal women, according to a study published June 29, 2026, in Frontiers in Public Health.¹ Women living in lower neighborhood-level socioeconomic status (nSES) communities experienced up to 3 times greater bone mineral density (BMD) loss from the same levels of air pollution exposure compared with women in higher-income neighborhoods, according to a press release from Mount Sinai Health System.²

Researchers at the Icahn School of Medicine at Mount Sinai's Institute for Health Equity Research analyzed data from 9,041 postmenopausal women enrolled at 40 clinical sites in the United States participating in the Women's Health Initiative (WHI), combining the randomized clinical trial cohort (n = 4,202) and the observational study cohort (n = 4,839).^1,2 The study evaluated ambient concentrations of nitrogen dioxide (NO₂), nitrogen oxide (NO), and sulfur dioxide (SO2), across 1-, 3-, and 5-year periods preceding BMD assessment, against individual- and neighborhood-level social determinants of health, including educational attainment, family income, and nSES (potential effect modifiers).¹

Neighborhood-level disparities and bone density

“A 10% increase in NO₂ was suggestively associated with 1.4 to 3.8 times greater BMD loss in low vs. high nSES participants across all measured sites,” found the study authors.¹

At the lumbar spine specifically, 1-year BMD loss per 10% NO₂ increase was β = -0.047 (95% CI, -0.066 to -0.027) in the low nSES group vs. β = -0.013 (95% CI, -0.023 to -0.001) in the high nSES group (P-interaction = 0.001).¹ Suggestive associations were also observed for NO, while nSES interactions were null for SO₂.¹

According to the findings, a 10% increase in NO₂ exposure was associated with an almost 4 times greater lumbar spine BMD loss among women in the lowest-nSES communities vs. those in the highest. Further, whole-body BMD declined approximately 8 times more among women in lower-nSES communities exposed to NO, and at the hip, a 10% increase in NO₂ was associated with approximately 6 times greater BMD loss in lower-nSES communities, with similar patterns observed for NO across all exposure periods.²

Income and education as additional modifiers

For income specifically, NO was suggestively associated with lumbar spine bone loss in all exposure periods, with only the 3-year average NO₂ exposure being suggestively associated with whole-body BMD (P = 0.048), with no interaction observed for SO₂.¹ Participants with lower educational attainment showed greater NO-related lumbar spine bone loss, while SO₂ showed the opposite pattern at multiple sites, and NO₂ showed no associations with education.¹

"These findings show that air pollution does not affect everyone equally," said Diddier Prada, MD, PhD, assistant professor of Population Health Science and Policy, and Environmental Medicine, at the Icahn School of Medicine at Mount Sinai, and first author of the study.

"Women living in socioeconomically disadvantaged neighborhoods experienced substantially greater bone loss despite similar pollution exposure,” said Prada in a press release. “Our findings underscore how environmental and social conditions work together to influence long-term bone health."²

Impact of osteoporosis-related fractures

The study authors noted that osteoporosis-related fractures affect an estimated 2.1 million Americans each year and generate approximately $22 billion in direct health care costs annually.²

"Our findings demonstrate that the health effects of air pollution are shaped not only by environmental exposure, but also by the communities where people live," Prada said. "Multiple factors likely contribute to this disparity, including greater proximity to pollution sources, housing conditions that may allow more outdoor pollutants indoors, and barriers to preventive care and osteoporosis screening."²

The authors concluded that reducing social inequities may improve the bone health of older women living in areas with high air pollution, while noting that additional studies are needed to generalize the findings to younger women and men, as only older women were analyzed in this cohort.¹

References:

1. Prada D, Ramírez A, Rajendrakumar AL, et al. Social determinants of health modify associations between air pollution and bone mineral density loss in postmenopausal women. Front Public Health. Published online June 29, 2026. Accessed June 30, 2026. https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2026.1832667/full
2. Equal exposure, unequal impact: for first time, Mount Sinai researchers show how air pollution causes greater bone loss in some women 50+. Mount Sinai Health System. Published June 30, 2026. Accessed June 30, 2026. https://www.newswise.com/articles/equal-exposure-unequal-impact-for-first-time-mount-sinai-researchers-show-how-air-pollution-causes-greater-bone-loss-in-some-women-50