Study says PFAS in U.S. tap water may average twice official figures

Who's involved

• Gehendra KharelEnvironmental scientist at Texas Christian University

The facts

• About 98% of 1.86 million EPA drinking water data points fell below minimum reporting level.^{1 2} Stated by 2 sources
• Using computer models, average PFAS for six regulated chemicals rose to 5.2 nanograms per liter from 2.6 when counting below-limit results as zero.^{1 2} Stated by 2 sources
• EPA's 2024 rule set enforceable limits of 4 parts per trillion for PFOA and PFOS, plus limits for PFHxS, PFNA, GenX and mixture hazard index.²
• Study does not establish that every below-limit result poses a health risk.^{1 2} Stated by 2 sources
• Researchers released PFAS-CAST tool for water agencies to apply the same statistical approach to their data.²

Who said what

These are statements and claims made by the people involved. They are reported, not verified.

• Gehendra Kharel, environmental scientist at Texas Christian University Method gives water agencies and utilities a way to account for the difference between counted-as-zero and modeled values.²
• Study researchers Standard reports may understate the average by 56 percent.²
• Study researchers More sensitive testing and more extensive monitoring of water systems are needed.²