"Researchers found that treating PFAS measurements below laboratory reporting limits as “zero” may underestimate how widespread the chemicals are in U.S. drinking water."
"When PFAS concentrations in drinking water fall below laboratory reporting limits, they are sometimes treated as “zero” in statistical analyses. But a new study published in Cell Reports Sustainability, which reanalyzed federal monitoring data, found that estimated PFAS concentrations in U.S. drinking water could be more than twice as high as calculations that treat results below laboratory reporting limits as zero suggest.
PFAS are a group of thousands of synthetic chemicals used for decades in products ranging from nonstick cookware to waterproof clothing. Often called “forever chemicals,” they break down very slowly in the environment and have contaminated drinking water supplies across the United States.
“About 98 percent of the roughly 1.86 million individual PFAS test results in EPA’s January 2026 dataset were below reporting limits,” said the study’s author, Gehendra Kharel, an associate professor of environmental and sustainability sciences at Texas Christian University.
But even without an exact concentration, he said, “those records still tell us something”—that PFAS contamination of drinking water is far more prevalent than generally acknowledged.
Newsletters "
Alissa de Chassey reports for Inside Climate News October 23, 2026.
SEE ALSO:
"Drinking Water May Have Much More ‘Forever Chemicals’ Than EPA Reports" (Washington Post)
"Researchers Find Widespread PFAS Contamination in Florida Waterways" (Inside Climate News)
