The Silent Link Between Climate Change and Breast Cancer: Why It’s Time We Paid Attention

By Dr Jasmina Kevric, Specialist Breast Surgeon

In 2022, more than 2.3 million women around the world were diagnosed with breast cancer, and 670,000 died from the disease (WHO, 2023). By 2050, the number of new cases is projected to rise by 38%, and deaths by 68%, with low-income countries shouldering the greatest burden (Global Cancer Observatory, 2022).

As a breast surgeon and public health researcher, I’ve spent my career focused on the traditional tools of cancer prevention: early detection through screening, healthy diet and exercise, avoiding smoking and alcohol. But a growing body of evidence points to another, less visible risk: the environment around us.

Pollution Is a Proven Carcinogen

In 2013, the International Agency for Research on Cancer (IARC) classified outdoor air pollution as a Group 1 carcinogen, alongside asbestos and tobacco (Loomis et al., 2013). While this designation was based primarily on its link to lung cancer, more recent studies now connect air pollution to breast cancer as well.

A U.S. cohort study found that each 10 µg/m³ increase in fine particulate matter (PM₂.₅) was associated with an 8% higher risk of estrogen receptor–positive (ER+) breast cancer (Niehoff et al., 2023). Similarly, a European analysis of six large studies showed a 6% increase in breast cancer risk for every 5 µg/m³ increase in PM₂.₅ (Andersen et al., 2022). The danger is greatest for women living near major roads and industrial zones, where pollutants like nitrogen dioxide (NO₂), nitrogen oxides (NOₓ), and polycyclic aromatic hydrocarbons (PAHs) are concentrated (White et al., 2018).

These pollutants don’t just linger in the air, they enter our lungs and bloodstream, reaching breast tissue (Hill & Wynder, 1979). Some have been linked to changes in DNA methylation in breast cancer–related genes (White et al., 2016), and others to increased breast density, a known breast cancer risk factor (DuPre et al., 2017; Yaghjyan et al., 2017).

Climate Change Worsens Chemical Exposure

Climate change adds a dangerous layer to this picture. A study across 17 countries in the Middle East and North Africa found that every 1 °C increase in temperature was associated with hundreds more cases of breast cancers per 100,000 women (Mousavi et al., 2023).

Rising temperatures worsen pollution, increase chemical runoff, and fuel wildfires that release carcinogens. One group of particular concern is PFAS—per- and polyfluoroalkyl substances, commonly called “forever chemicals.” Found in non-stick cookware, waterproof makeup, and fast-food packaging, PFAS don’t break down and are now widely present in our environment.

A 2022 meta-analysis linked PFAS, particularly PFOA and PFHxS, to higher breast cancer risk (Kwiatkowski et al., 2022). PFHxS has also been associated with increased breast density (Winkens et al., 2023).

Endocrine Disruptors Are Everywhere

These “forever chemicals” are part of a broader group called endocrine-disrupting chemicals (EDCs), which include:

• Phthalates in fragrances and plastics

• Parabens in cosmetics and personal care products

• BPA in food containers and receipts

• Legacy pesticides like DDT and chlordane

These chemicals mimic or interfere with estrogen hormonal disruption that can increase breast cancer risk. Lifetime exposure to estrogen remains one of the strongest known drivers of breast cancer (Key et al., 2001), and emerging research shows that even women without genetic risk factors may be vulnerable (Apostolou & Fostira, 2013).

Some communities bear more risk than others. Women of colour and those in low-income areas often have higher exposures, due to less regulation and targeted product marketing (James-Todd et al., 2022).

A New Era in Breast Cancer Prevention

Australia’s National Cancer Plan already identifies climate change as a critical public health issue, highlighting skin and lung cancers as climate-sensitive diseases (Australian Cancer Plan, 2023). But we now have enough evidence to add breast cancer to this model. Air pollution, chemical exposures, and rising heat are shifting the landscape of cancer risk, and our prevention strategies must evolve accordingly.

What can you do? Start by reducing your exposure:

• Get regular breast cancer screenings

• Use fragrance-free and paraben-free personal care products

• Avoid microwaving plastic containers

• Switch to PFAS-free cookware

• Filter indoor air, especially near busy roads

• Support policies for clean air and environmental regulation

As both a surgeon and public health doctor, I urge us to act. A cleaner, safer environment isn’t just good for the planet, it’s essential for cancer prevention.

References

• Apostolou, P., & Fostira, F. (2013). Hereditary breast cancer: the era of new susceptibility genes. Biomed Res Int, 2013:747318.

• Andersen, Z. J., Ravnskjær, L., Andersen, K. K., et al. (2022). Long-term exposure to fine particulate matter and breast cancer incidence: A pooled analysis. Environ Int, 161:107113.

• Australian Cancer Plan. (2023). Climate Change and Environmental Health Crises. Retrieved from: https://www.australiancancerplan.gov.au/climate-change-and-environmental-health-crises

• DuPre, N. C., Hart, J. E., Holmes, M. D., et al. (2017). Particulate matter and breast density in the Nurses’ Health Study II. Am J Epidemiol, 186(7): 730–738.

• Global Cancer Observatory. (2022). Breast cancer statistics. Retrieved from: https://gco.iarc.fr

• Hill, L. D., & Wynder, E. L. (1979). Environmental factors in breast cancer. Cancer, 43(5 Suppl):2056-66.

• James-Todd, T., Terry, M. B., Rich-Edwards, J., et al. (2022). Racial/ethnic disparities in exposures to endocrine-disrupting chemicals. Environ Health Perspect, 130(2):025002.

• Key, T. J., Verkasalo, P. K., & Banks, E. (2001). Epidemiology of breast cancer. Lancet Oncol, 2(3):133-140.

• Kwiatkowski, C. F., Andrews, D. Q., Birnbaum, L. S., et al. (2022). Scientific basis for managing PFAS as a chemical class. Environ Int, 145:106118.

• La Merrill, M. A., Vandenberg, L. N., Smith, M. T., et al. (2020). Consensus on key characteristics of EDCs as cancer hazards. Environ Res, 180:108884.

• Loomis, D., Grosse, Y., Lauby-Secretan, B., et al. (2013). The carcinogenicity of outdoor air pollution. Lancet Oncol, 14(13):1262–1263.

• Mousavi, S. H., Moradi, S., & Valipour, M. (2023). Global warming and cancer: an ecological study. Environ Int, 170:107986.

• Niehoff, N. M., Engel, L. S., White, A. J. (2023). Air pollution and breast cancer risk in the Sister Study cohort. JNCI: Journal of the National Cancer Institute, djad134.

• White, A. J., Gregoire, A. M., Niehoff, N. M., et al. (2016). Exposure to multiple sources of PAHs and DNA methylation in breast cancer-related genes. Environ Res, 148:144–149.

• White, A. J., Sandler, D. P. (2018). Environmental factors and breast cancer risk. JNCI, 110(6):djx096.

• White, A. J., Nichols, H. B., Bradshaw, P. T., et al. (2019). Air pollution and breast cancer risk. Environ Health Perspect, 127(5):057012.

• WHO. (2023). Breast cancer: key facts. Retrieved from: https://www.who.int/news-room/fact-sheets/detail/breast-cancer

• Winkens, K., Vestergren, R., Berger, U., et al. (2023). PFAS exposure and mammographic breast density. Environ Int, 175:107788.

• Yaghjyan, L., Satia, J. A., Rimm, E. B., et al. (2017). PM2.5 and breast density. Cancer Causes Control, 28(9): 967–975.

• Zhou, Y., et al. (2025). [Upcoming study on urban pollution and breast cancer incidence in China]. Journal TBD.