In 2024, the EPA set enforceable drinking water limits for PFOA and PFOS, marking a watershed moment in water safety. Yet millions of Americans still don't know if these forever chemicals are in their tap water, what health risks they pose, or what they can do about it. This guide breaks down the science, regulations, and practical steps you need to protect your family.
What Are Forever Chemicals (PFAS)?
Forever chemicals are human-made compounds that don't break down naturally in the environment or in your body. The formal name is per- and polyfluoroalkyl substances, or PFAS. They're called "forever" because their carbon-fluorine bonds are some of the strongest in chemistry, meaning they persist indefinitely.
PFAS have been manufactured since the 1940s for use in nonstick cookware, food packaging, water-resistant fabrics, aqueous film-forming foams (AFFF), and industrial processes. Because they repel water and grease, they're extremely useful, but that same property makes them resist degradation in nature and in the human body.
The PFAS family includes thousands of chemicals, but the two most studied and regulated are PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonate). These are the ones in the EPA's new drinking water standards.
EPA's 2024 Drinking Water Standards: What Changed
The New Maximum Contaminant Levels (MCLs)
In June 2023, the EPA proposed drinking water limits for PFOA and PFOS. By June 2024, these became enforceable national standards for all public water systems. Here's what that means:
- PFOA: 4.0 parts per trillion (ppt)
- PFOS: 4.0 parts per trillion (ppt)
To put this in perspective, 1 ppt is like one drop of water in 20 Olympic-sized swimming pools. The EPA also set limits for PFNA (perfluorononanoic acid) at 10 ppt and established a hazard index for four additional PFAS chemicals when they occur together in water.
Public water systems are required to test for these contaminants and notify customers if levels exceed the MCLs. However, private wells are not covered by these federal rules, meaning millions of Americans on well water have no federal requirement for testing.
What This Means for Your Tap Water
The new EPA standards apply to public water systems serving more than 25 people. Water utilities have until 2026 to comply, giving them time to install treatment systems or find alternative water sources. If your water system exceeds the new limits, your water provider must notify you and begin corrective action.
If you're on a private well, the EPA standards don't apply, but that doesn't mean you're safe. Private well contamination follows no federal standard, making private wells a significant blind spot in American water safety.
Beyond PFOA and PFOS: The Emerging PFAS Problem
Which PFAS Are Regulated vs. Unregulated
The EPA's 2024 standards regulate only five PFAS chemicals (PFOA, PFOS, PFNA, and a hazard index for four others). But the PFAS family contains over 12,000 known compounds, and most remain completely unregulated.
This creates a significant gap: manufacturers can phase out PFOA and PFOS and replace them with other PFAS that have less testing and no legal limits. This is called "regrettable substitution," and it's a growing concern among scientists.
Currently regulated PFAS in drinking water:
- PFOA (perfluorooctanoic acid)
- PFOS (perfluorooctane sulfonate)
- PFNA (perfluorononanoic acid)
- PFHxS (perfluorohexane sulfonate)
- PFBS (perfluorobutane sulfonate)
- GenX (a PFOA replacement)
Emerging PFAS chemicals with growing concern:
- PFBS and PFHxS (replacements for PFOS)
- GenX (DuPont's PFOA alternative)
- ADONA and F-53B (Chinese alternatives)
Many water systems haven't tested for these newer chemicals, so they may be present without anyone knowing it.
Where PFAS Contamination Occurs: State-by-State Patterns
Hotspots and Risk Factors
PFAS contamination is not evenly distributed. Certain areas have much higher rates of detection. Contamination typically occurs near:
- Military bases (because of AFFF use in fire training)
- Airports
- Industrial manufacturing sites
- Landfills and wastewater treatment plants
- Textile and leather processing facilities
- Fluoropolymer manufacturing plants
States with the most documented PFAS contamination include Massachusetts, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, and Vermont. However, PFAS has been detected in water systems in all 50 states.
To find out if PFAS has been detected in your area, check your local water utility's annual Consumer Confidence Report (CCR), which is publicly available online. You can also enter your ZIP code in ClearWater's free lookup tool to see if your water system has reported PFAS testing results.
Private Well Contamination Risk
Private wells near military installations, airports, or industrial sites face elevated PFAS risk. The CDC's National Health and Nutrition Examination Survey (NHANES) found PFOA and PFOS in the blood of about 97% of Americans, suggesting widespread exposure from multiple sources including drinking water.
If you rely on a private well, particularly in or near a known PFAS hotspot, testing is strongly recommended. Private well testing is not federally mandated, making it your responsibility to verify water quality.
Health Risks: Who Is Most Vulnerable
General Health Effects of PFAS Exposure
PFAS chemicals accumulate in blood and organs over time. While humans excrete some PFAS slowly, complete elimination can take years. Research links PFAS exposure to several health concerns:
- Cholesterol effects: Multiple studies show elevated PFOA and PFOS exposure correlates with higher cholesterol levels, even at low concentrations.
- Immune suppression: Prelim laboratory studies suggest PFAS may reduce immune response to vaccines and infections.
- Thyroid hormone disruption: Animal and limited human studies indicate PFAS may interfere with thyroid function.
- Pregnancy complications: Elevated PFAS exposure has been linked to increased blood pressure during pregnancy and higher cholesterol.
- Kidney and liver effects: Some studies show associations with reduced kidney or liver function at higher exposures.
- Cancer: EPA classified PFOA as "likely carcinogenic" based on animal and human evidence, though direct causation in humans remains under study.
The EPA's 2024 MCL for PFOA (4 ppt) is based on animal studies and a one-in-a-million cancer risk standard, the agency's typical benchmark for carcinogens.
Vulnerable Populations
Pregnant women and nursing mothers: PFAS crosses the placenta and appears in breast milk, potentially affecting fetal development and early childhood immune function.
Infants and young children: Pound for pound, children drink more water than adults and have developing immune and endocrine systems more sensitive to chemical disruption.
People with existing kidney or liver disease: Since PFAS accumulates in organs and is slowly excreted, individuals with compromised kidney or liver function may accumulate higher concentrations.
People with high cholesterol: If PFAS exposure increases cholesterol, individuals already at cardiovascular risk may face compounded effects.
Testing Your Water: How to Know What You Have
Public Water Systems
Your water utility is now required to test for PFOA and PFOS (and other emerging PFAS under the 2024 rule). Each year, they publish a Consumer Confidence Report (CCR) showing what they tested for and what they found.
Steps to access your water test results:
- Go to your local water utility's website or call their customer service department.
- Request the most recent Consumer Confidence Report (often called a Water Quality Report).
- Look for PFOA and PFOS results. They should list the contaminant name, the level detected (in ppt), and whether it exceeds the MCL of 4 ppt.
- If PFAS exceeds the standard, your utility is required to notify you separately and explain what actions they're taking.
Alternatively, you can enter your ZIP code into ClearWater's free tool, which pulls publicly available water quality data so you can see what contaminants have been detected near you.
Private Wells
Private wells are not tested by the EPA. Testing is entirely your responsibility. Most state health departments provide lists of certified private well laboratories. PFAS testing typically costs between $200-500 per sample, depending on how many PFAS chemicals you're testing for.
If you're in a known PFAS hotspot (near a military base, airport, or industrial site), testing is highly recommended. If your well tests positive, follow up with your state's environmental or health department for guidance on treatment and potential health effects.
Removing PFAS from Your Tap Water
How PFAS Gets Into Your Home
PFAS in tap water comes from your water source, not from plumbing or fixtures. Once it's in the water supply, the only way to remove it is through treatment at the point of use (your home) or point of entry (your water utility).
Treatment Technologies That Work
Activated Carbon Filters (granular and cartridge): Activated carbon can remove PFAS, but effectiveness depends on the specific type of carbon, contact time, and which PFAS chemicals are present. Some carbon filters remove PFOA and PFOS well, while others are less effective. Pitcher filters and basic faucet-mounted filters often don't have sufficient contact time to remove PFAS reliably. Whole-home activated carbon systems are more effective.
Ion Exchange Resins: These systems use charged resin beads to trap PFAS molecules. They're highly effective for PFOA and PFOS but can require frequent cartridge replacement and produce concentrated PFAS waste during regeneration.
Reverse Osmosis (RO): RO systems force water through a semi-permeable membrane and can remove most PFAS, including PFOA and PFOS. They're effective but waste water (typically 3-5 gallons wasted for every 1 gallon of clean water produced) and reduce water pressure.
Distillation: Boiling water and collecting the steam effectively removes PFAS, but it's energy-intensive and impractical as a whole-home solution. It works for small volumes like drinking and cooking water.
Treatment that doesn't work: Standard pitcher filters, basic sediment filters, and boiling water do not remove PFAS. Boiling concentrates PFAS because water evaporates but PFAS remains.
Choosing the Right Treatment for Your Situation
If PFAS is detected in your public water system: Your water utility may install or recommend treatment options. If you want additional home treatment, activated carbon filters or reverse osmosis are most reliable. Consider point-of-use systems (under-sink or pitcher) if you're primarily concerned with drinking and cooking water, or whole-home systems for comprehensive protection.
If you're on a private well with confirmed PFAS contamination: Whole-home treatment is essential because you cannot rely on utility-provided treatment. Consult with a water treatment professional to assess which PFAS chemicals are present and which technology is most suitable for your specific contamination profile.
If you're in a known PFAS hotspot but haven't tested: First, test your water to confirm whether PFAS is actually present. Then treat based on results, not assumptions. Installing expensive treatment for a problem that doesn't exist isn't necessary.
If PFAS levels are very high: Ion exchange or reverse osmosis are typically more effective than activated carbon alone. Consult a water treatment specialist to design a system appropriate for your contaminant levels.
What You Can Do Right Now
Today
- Check your local water utility's latest Consumer Confidence Report for PFAS testing results. If you can't find it online, call your water department and ask for it.
- If you're on a private well, particularly near a military base, airport, or industrial site, contact your state health department about PFAS testing options.
This Week
- If PFAS is detected in your water system above 4 ppt, your utility is required to notify you. Check your mail or email for official notices.
- If you haven't already, take the ClearWater free water quality lookup to see what contaminants have been detected in your area, not just PFAS.
This Month
- If PFAS is confirmed in your water, consult with a water treatment professional to determine whether point-of-use or whole-home treatment is appropriate for your situation.
- If you're on a private well with PFAS risk, obtain a water test. Most state environmental agencies provide lists of certified labs and can advise on next steps if contamination is found.
The Bottom Line
Forever chemicals are a real and measurable drinking water concern, but the 2024 EPA standards represent meaningful progress. Public water systems now have enforceable limits for PFOA and PFOS, and utilities are required to test and notify customers. However, coverage gaps remain, particularly for private well users and for the thousands of unregulated PFAS chemicals still entering the market.
The key steps are: know your water quality, understand your contamination profile (not just PFAS), and choose treatment based on your actual risk, not fear. Most Americans can obtain reliable water information from their water utility's public reports, and the EPA's new standards reflect current science on safe exposure limits.
If you're uncertain about your water quality or need help interpreting results, ClearWater's free lookup tool provides a starting point, and your local water utility or state environmental agency are authoritative resources for specific guidance.