Per- and polyfluoroalkyl substances (PFAS) — widely known as “forever chemicals” — are found in everyday products like nonstick pans, waterproof gear, and food packaging. While these substances accumulate in the human body and are associated with health risks like high cholesterol, developmental delays, and certain cancers, new research reveals a possible internal cleanup system: gut bacteria.
How gut microbes deal with chemical exposure
Bacteria regularly face chemical stressors in their environment—pesticides, medications, pollutants—and have developed methods to neutralize or store them. A molecular biologist at the University of Cambridge, Kiran Patil, explains, “From the bacterial perspective, chemicals are chemicals.” Previous work showed some gut microbes accumulate therapeutic drugs; however, how they handle environmental toxins like PFAS was unclear.
Lab results: microbes soak up PFAS
In lab experiments, researchers exposed multiple strains of human gut bacteria—including E. coli—to two common PFAS variants and other contaminants. They discovered that bacteria internalized PFAS, clustering the chemicals within their cells. Depending on the strain, bacteria absorbed between 20% and 75% of available PFAS, with no harmful effects to themselves.
Testing in mice: human microbes help eliminate PFAS
To see if this process works in a live organism, scientists used “humanized” mice—animals whose gut microbiome was replaced with human-derived strains. When these mice were fed PFAS, they excreted significantly more of the chemicals in feces compared to germ-free mice, indicating the bacteria were actively removing PFAS from the body.
Implications and future directions
These findings, published on July 1 in Nature Microbiology, indicate that certain gut microbes can bind internally to PFAS and enhance their removal via poop. The next phase? Conducting human studies to track how PFAS levels vary with different gut microbiome profiles. Another potential application could be probiotics specifically designed to boost bacteria that absorb PFAS.
A broader strategy for PFAS detox
To date, efforts have primarily targeted PFAS removal from the environment. These new insights suggest we might also harness gut microbes as a living detox system. As Patil summarizes: “Our microbiome does a lot for us, and maybe they can help with PFAS too.”