Study finds 'forever chemical' exposure increases risk of certain cancers in women

Exposure to a range of widely used chemicals may significantly increase the odds of certain hormonally driven cancers in women, according to U.S. government-funded research published Monday.

In a study appearing in the Journal of Exposure Science & Environmental Epidemiology, researchers analyzed data collected by the U.S. Centers for Disease Control and Prevention and found that women exposed to per- and polyfluoroalkyl substances (PFAS), phenols, and parabens had higher odds of having been diagnosed with cancers of the breast, ovary, skin, and uterus.

Researchers from the University of Southern California, University of Michigan, and University of California, San Francisco linked exposure to PFAS compounds PFDE, PFNA, and PFUA with a doubling or near-doubling in the odds of a previous melanoma diagnosis and, for PFNA, an elevated risk of uterine cancer. Women with higher exposure to BPA—which is used in many plastic products—and 2,5-dichlorophenol, a chemical found in many dyes, had higher odds of a previous ovarian cancer diagnosis.

"People should care about this because we know that there is widespread human exposure to these chemicals."

The study also found that "various associations between environmental chemical exposures and previous cancer diagnoses were modified by race," including in Black, Latina, and Asian women targeted by advertisements for hair-straightening and skin-lightening products containing phthalates, and phenols.

"People should care about this because we know that there is widespread human exposure to these chemicals and we have documented data on that," Max Aung, an assistant professor of environmental health at the University of Southern California's Kreck School of Medicine and a senior author of the study, toldThe Guardian.

“These chemicals can increase the risk of various different health outcomes and they can alter your biological pathways," Aung added. "That is important to know so that we can better prevent exposures and mitigate risks."

Commonly called forever chemicals because they do not biodegrade and accumulate in the human body, PFAS have myriad uses, from nonstick cookware to waterproof clothing to firefighting foam. According to the U.S. Agency for Toxic Substances and Disease Registry, PFAS is also linked to cancers of the kidneys and testicles, low infant weight, suppressed immune function, and other adverse health effects. It is found in soil and water around the world and is present in almost everyone's blood.

A 2020 Environmental Working Group study found more than 200 million Americans could have PFAS in their drinking water. The advocacy group maintains an interactive map showing more than 2,800 PFAS-contaminated sites in all 50 states, Washington, D.C., and multiple U.S. territories.

Investigative journalism and congressional hearings beginning in 2018 have revealed that chemical giants DuPont and 3M understood—and covered up—the extreme toxicity of PFAS, drawing subsequent comparisons with how Big Tobacco for decades conspired to conceal the deadly dangers of cigarettes.

The Bipartisan Infrastructure Law signed by President Joe Biden in 2021 allocated $9 billion to mitigate PFAS contamination in U.S. drinking water systems. However, other congressional efforts to limit and remediate PFAS contamination have died under intense lobbying from the chemical industry.