Study Links Common Chemical Exposure to Aggressive Cancer Type

WHO:

NY Post - National Institutes of Health (NIH) researchers reported an association between exposure to two “forever chemicals” and aggressive estrogen receptor-negative (ER-negative) breast cancer.

Fox News - Study leader Alexandra White, Ph.D., is an NIH researcher; first author Che-Jung Chang, Ph.D., was an NIH research fellow and is now a researcher at DLH.

Fox News - HHS Secretary Robert F. Kennedy Jr. said women “deserve clear answers about how chemicals in their environment may affect their health.”

Fox News - Dr. Tiffany Troso-Sandoval, a New York City-based breast and gynecological cancer specialist, worked at Memorial Sloan Kettering for more than 25 years.

WHAT:

NY Post - Women in the highest exposure groups had up to a 93% higher rate of ER-negative breast cancer; the figures compare groups and do not represent an individual woman’s chance of developing cancer.

Fox News - The study, published in the Journal of Clinical Oncology, examined perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). The highest PFOA group had a 67% higher rate of ER-negative breast cancer, and the highest PFOS group had a 93% higher rate than the lowest group.

Fox News - Researchers found no clear association between PFOA or PFOS and breast cancer overall. The findings show association, not proof of causation; the authors said more research is needed.

Fox News - ER-negative breast cancers tend to be more aggressive and have worse outcomes than cancers that respond to estrogen.

Fox News - White said the study and an accompanying meta-analysis of previous research “provide[] evidence that two PFAS are related to a higher ER-negative breast cancer risk.”

WHERE:

Fox News - Data came from the U.S. Sister Study, a project examining environmental and genetic factors related to breast cancer.

Fox News - Troso-Sandoval is based in New York City.

HOW:

Fox News - Researchers measured 17 PFAS in pre-diagnosis blood samples from 1,609 women who later developed breast cancer and a comparison group of 2,269 women. Every participant had a sister diagnosed with breast cancer at enrollment, and none had breast cancer then.

Fox News - PFAS are synthetic chemicals that break down slowly and can accumulate in the environment and human body. They have been used in non-stick cookware, upholstery, clothing, some food packaging, and personal-care items.

Fox News - The research focused mainly on older PFAS that have largely been phased out; White said little is known about replacement chemicals, which may be shorter-chain and less persistent.

Fox News - Troso-Sandoval suggested reviewing frequently used products, considering stainless-steel cookware, avoiding heating food in plastic containers, and reviewing cosmetics and personal-care products. Chang said exposure is “potentially modifiable.”

(UPDATED November 10, 2026 18:03 UTC)

NIH researchers linked two persistent chemicals to higher rates of aggressive breast cancer. The highest-exposure groups had rates up to 93 percent higher, but causation remains unproven. Researchers found no clear link to breast cancer overall; more research is needed.