Researchers at the Icahn School of Medicine at Mount Sinai have found that exposure to per- and polyfluoroalkyl substances (PFAS), commonly known as "forever chemicals," during pregnancy and early life is associated with increased intestinal inflammation during childhood.
The findings, published July 10, 2026, in Clinical Gastroenterology and Hepatology , provide new evidence that environmental exposures during critical stages of development may influence long-term intestinal health and future inflammatory bowel disease (IBD) risk.
The study is the first to demonstrate that prenatal and early-life PFAS exposure is consistently associated with elevated levels of fecal calprotectin—a biomarker of intestinal inflammation commonly used to monitor IBD—across three birth cohorts in the United States and Mexico.
Researchers measured PFAS concentrations in maternal blood collected during pregnancy, umbilical cord blood, and newborn dried blood spots before following children for up to 11 years. Across all three birth cohorts, higher PFAS mixture levels were associated with higher fecal calprotectin levels later in childhood.
"While genetics play an important role in inflammatory bowel disease, they do not fully explain why the disease develops," said Manasi Agrawal, MD, MS, corresponding author of the study and Assistant Professor of Medicine (Gastroenterology), and Environmental Medicine and Public Health, at the Icahn School of Medicine. "Our findings suggest that prenatal and early-life PFAS exposure may contribute to intestinal inflammation during an important stage of development. Understanding these environmental influences may ultimately help us identify opportunities to reduce future disease risk before symptoms develop."
PFAS are a large family of synthetic chemicals used in products including nonstick cookware, food packaging, stain-resistant fabrics, and firefighting foams. Because these chemicals do not readily break down, they persist in the environment and can accumulate in the human body over time, leading to widespread human exposure.
Using advanced untargeted chemical analysis, the investigators detected PFAS across all early-life biological samples. They found that both legacy PFAS compounds and newer replacement PFAS were associated with intestinal inflammation, suggesting that a broad range of these chemicals may influence children's gut health.
"By studying PFAS as mixtures rather than individual chemicals, we were able to better reflect how people are exposed in everyday life," said Vishal Midya, PhD, MStat, first author of the study and Assistant Professor of Environmental Medicine and Public Health at the Icahn School of Medicine. "The consistency of our findings across multiple biological samples and three independent birth cohorts strengthens the evidence that early-life PFAS exposure may have lasting effects on intestinal health."
The researchers emphasize that elevated fecal calprotectin does not mean a child will develop IBD. Rather, it is a sensitive biomarker of intestinal inflammation that has been associated with an increased future risk of IBD. Because the study was observational, it cannot determine whether PFAS directly cause intestinal inflammation or IBD.
The research team plans to continue following participants to determine whether children with higher early-life PFAS exposure and intestinal inflammation are more likely to develop inflammatory bowel disease later in life. The findings also underscore the importance of public health strategies aimed at reducing PFAS exposure during pregnancy and early childhood.
The study included collaborators from the University of Iowa College of Public Health; the National Institute of Public Health in Cuernavaca, Mexico; Universidade de Lisboa, Portugal; Sheba Medical Center in Israel; and Aalborg University in Denmark.
The research was supported by the International Organization for the Study of Inflammatory Bowel Disease, the Crohn's & Colitis Foundation, the Leona M. and Harry B. Helmsley Charitable Trust, and the National Institute of Diabetes and Digestive and Kidney Diseases.
