Even Low Levels of Forever Chemicals in Tap Water Can Harm Babies Before Birth, New Research Shows

Exposure to PFAS (per- and polyfluoroalkyl substances)—toxic chemicals known as "forever chemicals"—through drinking water can harm infant health before birth, causing premature birth, low birth weight, and even infant mortality. A groundbreaking study from University of Arizona researchers examining over 11,000 births in New Hampshire between 2010 and 2019 found that babies born to people living downstream from a PFAS-contaminated site were far more likely to be born before 28 weeks of pregnancy and to weigh under 2 pounds at birth compared to those whose drinking water sources were upstream of the contaminated site.

How Severe Is the Risk to Infants?

The health impact is striking. The New Hampshire study found that living downstream from a PFAS-contaminated site was tied to an increase in infant mortality of 191%. Premature birth and low birth weight are key factors linked to infant mortality in the first year of life. A science review by the Environmental Working Group (EWG) found that PFAS are routinely detected in umbilical cord blood, crossing the placenta and reaching the developing fetus during pregnancy. This means exposure happens before a baby is even born.

The research methodology was particularly strong because all participants lived within about 3 miles of a PFAS-contaminated site. The only difference between the control and study groups was whether their drinking water source was upstream or downstream of the contamination. Notably, the pregnant people with the highest exposures and worst health outcomes were from more socioeconomically advantaged groups, which strengthens the case that PFAS exposure—rather than economic or social factors—played a major role in the poor birth outcomes.

Does Low-Level PFAS Exposure Still Cause Problems?

Yes. A 2025 study from California state scientists analyzed data collected between 2018 and 2020 and found that even low levels of PFAS in drinking water significantly increase blood levels of these chemicals. At least one type of PFAS was detected in the water of more than half the study participants. When participants had at least one detection of perfluorohexane sulfonic acid (PFHxS) in their untreated source water, they had 30% higher blood levels of that chemical.

The findings were even more striking when researchers examined finished drinking water at the tap. Blood levels were higher by 80% for PFHxS, 30% for PFOA, 31% for PFOS, and 42% for total PFAS when these chemicals were detected in the water people actually drank. Although the PFAS blood levels in the California study participants were lower than national averages and much lower than people in highly contaminated communities, 86% had levels linked to potential health harms according to 2022 clinical guidance from the National Academies of Sciences, Engineering, and Medicine.

What Are the Broader Health Risks Beyond Pregnancy?

PFAS exposure is linked to multiple serious health problems beyond reproductive harm. Exposure to these chemicals is associated with increased risks of certain cancers—most notably kidney and testicular cancer—as well as adverse effects on the immune system, thyroid function, liver, and kidneys. The medical costs associated with PFAS-related harms total approximately $8 billion annually across the United States, which is more than double the Environmental Protection Agency's (EPA) estimated annual costs of about $3.8 billion to treat PFAS in drinking water under its new regulations.

Ways to Reduce Your PFAS Exposure at Home

• Check your tap water: Use the EWG's Tap Water database to look up your water system by postal code or EWG's interactive map of PFAS in drinking water to find out what's in your water.
• Install home filtration: Use a reverse osmosis or carbon filter to reduce PFAS in your drinking water, though individual filtration systems may not suit every budget.
• Choose safer cookware: Use cast iron, stainless steel, and glass cookware instead of non-stick options that may contain PFAS.
• Avoid stain-resistant textiles: Reduce purchases of clothing or textiles marketed as "stain resistant" or "wrinkle resistant," as these often contain PFAS.
• Reduce household dust: Frequent vacuuming and dusting can lower household dust, which is another route of PFAS exposure.
• Check cosmetics: Use the EWG's Skin Deep database to avoid cosmetics with PFAS.

EWG research shows that PFAS contamination often occurs alongside multiple other chemicals, not in isolation—and properly designed filtration can reduce many of these contaminants at the same time.

What's Happening With Regulations?

The EPA finalized groundbreaking regulations for PFAS in drinking water in 2024, setting the first limits on the forever chemicals PFOA and PFOS and other PFAS. However, the agency has moved to scale back those regulations and delay compliance deadlines to 2031. Eleven states have set their own legal standards for drinking water, but a national standard is needed to protect all communities.

The case for strong PFAS regulations is strengthened by the reproductive health benefits alone. Even considering only the benefits to children's health, the public health gains from cleaning up PFAS-contaminated drinking water could justify the costs of treatment. The Southern California data serves as a model for a national challenge: PFAS are not just an industrial zone problem where the pollution occurs, but an everywhere problem. It's urgent that we address contamination at the source as well as treating drinking water.

If you're concerned about your family's exposure, contact your elected officials and let them know that drinking water safety and PFAS regulations are important to you and your family's health.