PFAS Water Test

Who should test for PFAS

The only way to know whether PFAS are in your water, and how much, is to have a lab measure them.

If you have a private well, nobody tests it for you. EPA says the quality of drinking water from private domestic wells is not regulated by the federal government under the Safe Drinking Water Act, nor by most state governments. State PFAS rules don't change that. Pennsylvania's Environmental Quality Board wrote that it does not have the authority to regulate private water sources, and Michigan says private residential wells are not regulated under the Safe Drinking Water Act. EPA's routine yearly well tests (total coliform bacteria, nitrates, total dissolved solids and pH) don't include PFAS, so you have to ask for a PFAS test.

You have the most reason to test if any of these describe your home:

• A possible source is nearby. EPA names firefighting foam used at airports, military bases and fire training sites, landfills and other waste sites, factories that make or use PFAS, and biosolids fertilizer used on farmland.
• Your state is investigating PFAS near you. In Michigan, when a project team decides wells near a known or suspected source need testing, EGLE mails the owners a letter offering to test the well for free.
• Someone in your home may be more exposed. EPA says pregnant and breastfeeding women drink more water per pound of body weight than the average person, and that children drink more water per pound than adults. Infant formula made with water that contains PFAS can expose babies.
• You have never tested for PFAS. Without a result there is nothing to compare with the benchmarks below.

If you are on public water, start with your water provider. EPA says many public water systems already have PFAS test results, and under the 2024 rule they must finish initial monitoring by 2027^[1] and share their PFAS levels with the public from then on. Michigan tested its public water supplies in a statewide survey and says that if you pay a water bill, your supply was most likely tested.

If you're on a well and want a broader baseline, build a test plan for your situation, and see our well water testing guide for the yearly well check.

Certified lab or home kit

A certified lab measures each PFAS. EPA says that if you test your water yourself, it is important to use a state-certified laboratory using EPA-developed testing methods. Michigan certifies labs for PFAS analysis using EPA Method 537.1 or Method 533, and says selecting a certified laboratory is strongly recommended. The lab reports a concentration for each PFAS it measures, which you can line up against the federal and state benchmarks.

The amounts are tiny. PFAS are reported in parts per trillion. EPA puts that in perspective: one part per trillion in time is like one second out of nearly 32,000 years^[2]. At that scale, Michigan warns, even the smallest cross-contamination could cause a false positive, so the sampling steps below matter as much as the analysis.

A home kit is not a substitute. A kit that does not report a measured concentration for each PFAS can't be compared with the limits on this page. If a decision depends on the answer, such as buying a filter, use a certified lab.

Questions to ask the lab before you order:

• Which PFAS does the report list? Make sure it includes PFOA, PFOS, PFHxS, PFNA and HFPO-DA (GenX).
• Does the kit come with PFAS-free bottles, ice packs, a cooler and powderless nitrile gloves? Michigan's guidance says the lab should provide these, along with a test request form and its own instructions.
• Does the kit include a control sample (a field blank), and what does it cost to analyze?
• How long will results take, and does the lab offer sample collection?

Where to find a lab. Michigan publishes a list of labs certified for PFAS, showing whether residents can request a kit and whether a technician can collect the sample. Pennsylvania DEP publishes a list of labs accredited to analyze PFOA and PFOS. For other states, look up certified labs and programs in your state. Our directory of certified water testing labs lists state-certified labs in the states we cover, and our guide to well water testing cost shows verified lab prices.

Lab methods

• EPA Method 533
• EPA Method 537.1

Sources: epa.gov (source for lab methods) (opens in a new tab), cfpub.epa.gov (source for lab methods) (opens in a new tab)

How to collect a PFAS sample

PFAS sampling is different from other water tests because PFAS are in many things we use every day. Michigan lists water- and stain-resistant products, cosmetics and lotions, insect repellents and sunscreens, pizza boxes and fast-food wrappers, recycled paper towels, and ordinary latex gloves. Always follow your lab's instructions first; Michigan says its guidance does not supersede them. The steps below come from Michigan's guidance for well owners and EPA Method 537.1, and explain what your kit is asking you to do.

Before sampling day

1. Get the kit. Use only the bottles and materials the lab sends. Bottles that did not come from the lab are on Michigan's prohibited list.
2. Freeze the ice packs for at least 24 hours^[8] before you sample. Don't use chemical or blue ice packs that did not come from the lab.

On the day

1. Dress for it. Skip anything waterproof, water-repellent or stain-resistant, and clothes that were recently dry-cleaned or washed with fabric softener.
2. Keep products away. Don't apply lotion, sunscreen or insect repellent near the sampling area, and don't handle fast food or wrapped snacks before or during sampling. Wash your hands with soap and water.
3. Pick the tap. Michigan recommends the kitchen faucet and cold water only. Don't use a sprayer or a leaky faucet head.
4. Label first. Fill in the bottle label and the lab's form, including the date and time, before you open the bottle. Use a ballpoint pen.
5. Flush the cold tap for three minutes^[8], then turn the flow down to about the thickness of a pencil. EPA Method 537.1 describes the same idea: let the water run until its temperature has stabilized, then sample from the flowing tap.
6. Fill the bottle. Put on the nitrile gloves. Open the bottle without setting the cap down or touching the inside. The bottle holds a powdered preservative, so don't rinse it out or let the bottle overflow. Fill it to the lab's line, cap it, and turn it over gently a couple of times to mix.
7. Handle the control sample if your kit has one: pour the lab's pre-filled bottle into the empty one and seal it. EPA explains that this field blank shows the lab whether PFAS got into the sample during collection.
8. Ship it cold. Pack the bottles with the lab's ice packs, keep the form out of the cooler or in a plastic bag, and ship for next-day delivery. The quick guide at the top of this page shows how long the lab has to work with the sample.

Common mistakes to avoid

• Using bottles, gloves or ice packs that did not come from the lab.
• Wearing water-resistant clothing or putting on sunscreen or insect repellent right before sampling.
• Rinsing the bottle, which washes out the preservative.
• Letting the sample warm up or sit before shipping.

What your PFAS level means

Your lab report gives a result for each PFAS it measured. Pennsylvania DEP states PFAS levels in nanograms per liter (ng/L) or parts per trillion (ppt), two names for the same amount. Compare each PFAS with its own benchmarks; the status box above shows where each one stands as of its date.

Federal limits: final, not yet in force. EPA's 2024 rule set a limit of 4.0 ng/L (effective Apr 26, 2029)^[1] for PFOA and 4.0 ng/L (effective Apr 26, 2029)^[1] for PFOS. Their health goals are 0 ng/L^[1] and 0 ng/L^[1]. The table below lists the limits for PFHxS, PFNA and HFPO-DA too. The rule also set a Hazard Index limit for mixtures of two or more of PFHxS, PFNA, HFPO-DA and PFBS, which this page does not evaluate. EPA says public water systems have five years, to 2029^[1], to reduce these PFAS if they exceed the limits. In May 2026 EPA proposed keeping the PFOA and PFOS limits with more time to comply, and rescinding the limits for the other three and the Hazard Index for mixtures. Those are proposals, not final rules.

Michigan limits are in force for public supplies, but challenged in court. Michigan's rule covers all five of these PFAS: PFOA 8 ng/L^[16], PFOS 16 ng/L^[16], PFHxS 51 ng/L^[16], PFNA 6 ng/L^[16] and HFPO-DA 370 ng/L^[16]. Michigan says it uses these limits, along with other factors, when it evaluates private well results. 3M's challenge to the rules is before the Michigan Supreme Court^[14]; the limits stay in force meanwhile, and we compare a Michigan result with them as a health guideline rather than a settled legal limit.

Pennsylvania limits PFOA and PFOS for public water systems, at 14 ng/L^[17] and 18 ng/L^[17].

For where PFAS come from, their health effects and how to lower them, see our guide to PFAS in well water.

Putting your result in context

• No PFAS detected. No treatment needed based on this result. If the sample was taken carefully, keep the report so you can compare future results.
• PFAS detected, below every benchmark. EPA says that if PFAS were measured but are below federal limits, a filter may not be useful to you. Keep the report and retest if something near your well changes.
• Above a benchmark. Retest with a state-certified lab to confirm. EPA suggests asking your state environmental or health agency what it recommends and, if you remain concerned, using another water source for drinking, cooking and baby formula while you decide. If you have health concerns, talk to a health professional.

Don't decide on treatment from a single reading you can't compare with these benchmarks. Any treatment choice should start from a confirmed certified-lab result and be checked with a retest afterward.