PFAS Drinking Water Exposure: Hidden Risks in Everyday Foods and California Water Supplies
A new study from May 14, 2025, led by Boston University School of Public Health, looked at PFAS chemical levels in the blood of 700 adults in California. At the same time, the study reviewed their diets and the quality of their drinking water. PFAS are man-made chemicals found in many everyday items. Although levels from food have dropped over the last 20 years due to government actions, the study found that drinking water is still a major source of exposure. Seafood, eggs, and brown rice were also linked to higher PFAS levels.
Because PFAS can stay in the body for a long time and may cause serious health problems, the study shows how important it is to keep testing water supplies and cleaning up contamination. Ecotox Environmental Services helps cities and water managers find and fix PFAS problems with advanced testing, sampling, and expert advice.
What the Study Looked At
The research team worked with the California Department of Public Health. They used data from the California Regional Exposure Study, collected between 2018 and 2020. They measured PFAS levels in blood samples using precise lab tools. This was the first study in the U.S. to connect PFAS levels in people’s blood with both their diets and local water sources.
Main Results
- Drinking Water is a Major Source: People who lived in areas with PFAS in their tap water had much higher levels of PFAS in their blood.
- Some Foods Still a Problem: Eating seafood, eggs, and brown rice was linked to higher PFAS levels. Other foods, like red meat and packaged snacks, showed weaker connections.
- Food Exposure is Going Down: Compared to earlier studies, people now get less PFAS from food. This shows that food safety rules are working.
Why PFAS Are Dangerous
PFAS are often called “forever chemicals” because they don’t break down easily. Once in the body, they can stay for years and build up over time. Exposure to PFAS has been linked to:
- Cancer: Especially kidney and testicular cancers.
- Liver and Thyroid Problems: Including changes in liver enzymes and hormone levels.
- Development and Fertility Issues: Such as problems with pregnancy and slower development in children.
Because of these risks, it is important to have strong water safety rules and to track PFAS at the source.
Government Rules and Next Steps
In 2023, the U.S. Environmental Protection Agency (EPA) set new limits for two common PFAS chemicals—PFOA and PFOS—at 4 nanograms per liter in drinking water. Full compliance was originally required by 2029, but the deadline has been pushed to 2031. Some rules for newer PFAS types, like GenX and PFHxS, were rolled back recently. Still, California continues to make its own rules stronger to better protect the public.
How Ecotox Can Help
Ecotox Environmental Services offers tools and support to help communities take action:
- Drinking Water Testing: Detailed PFAS tests using approved methods to meet the latest health and safety standards.
- Lab Analysis for Other Sources: Testing blood and food samples to track how PFAS is getting into the body.
- Smart Sampling Plans: Choosing the right way to collect water samples to detect changes over time and across different locations.
- Expert Advice and Custom Projects: Helping cities and water providers understand results, assess risks, and follow the law.
With help from Ecotox, water systems can find PFAS problem areas, plan clean-up efforts, and make sure drinking water stays safe—now and in the future.