New research from Sylvester Comprehensive Cancer Center at the University of Miami Miller School of Medicine suggests that women who live near federally designated Superfund sites face a higher risk of developing aggressive forms of breast cancer -- including triple-negative breast cancer, which is especially difficult to treat.

Previous research from the National Institutes of Health has shown that certain aggressive and treatment-resistant breast cancers are becoming more common. Building on those findings, three recent studies led by Sylvester researchers point to a connection between breast cancer risk, environmental contamination near Superfund sites, and social disadvantage. Superfund sites are locations polluted by hazardous waste that the Environmental Protection Agency has flagged for cleanup due to threats to human health or the environment.

Why Environmental Exposure Is Gaining Attention

The increase in aggressive breast cancer cases -- particularly hard-to-treat subtypes like triple-negative breast cancer -- has prompted scientists to take a closer look at environmental influences that may be contributing to these trends. In Florida, where 52 active Superfund sites remain, concerns raised by local communities helped bring the issue into focus. Members of Sylvester's Community Advisory Committee encouraged researchers to investigate whether living near these sites could affect cancer risk.

"Members of our community raised concerns that where they lived was making people sick," said Erin Kobetz, Ph.D., M.P.H., an epidemiologist and associate director for community outreach and engagement at Sylvester and the Judy H. Schulte Senior Endowed Chair in Cancer Research.

"Overwhelmingly, the people who were speaking up about this lived in a neighborhood relatively close to a Superfund site. There's a growing body of evidence that living in neighborhoods close to these sites is associated with poor health outcomes," she said.

Although the health effects of Superfund sites have been studied for decades, Kobetz noted that the relationship between environmental pollution and breast cancer has received far less attention. To address this gap, she assembled a multidisciplinary research team that included physicians, epidemiologists, and basic scientists. Using Sylvester's SCAN360 data portal, the group analyzed highly detailed data on neighborhood conditions and cancer risk across South Florida.

Proximity to Superfund Sites and Cancer Severity

In the first study, researchers reviewed more than 21,000 breast cancer cases diagnosed in Florida between 2015 and 2019. They examined whether living near a Superfund site was linked to more advanced disease. The analysis showed that women who lived in the same census tract as at least one Superfund site were about 30% more likely to be diagnosed with metastatic breast cancer.

The team then focused on triple-negative breast cancer (TNBC), an aggressive subtype with limited treatment options. Their findings showed that living near a Superfund site was also associated with a higher risk of TNBC. The researchers further explored exposure to particulate matter 2.5 (PM2.5), a type of air pollution made up of particles smaller than 2.5 microns. Higher levels of PM2.5 exposure were linked to increased TNBC risk in South Florida.