Lead and PFAS: certification, or it is just a claim

What is lead and pfas filtration?

Lead and PFAS are the two contaminants where product marketing has run furthest ahead of what products are verified to do. Two things are worth holding onto. First, lead usually enters your water from your own service line and household plumbing rather than from the treatment plant, so a utility report showing compliance genuinely cannot tell you what comes out of your tap. Second, the only claim worth anything is certification to the relevant standard for the specific contaminant - everything else is copy.

Signs you need lead and pfas filtration

• Your home was built in an era when lead service lines or lead solder were in normal use
• Your utility, city or state has notified you that your service line material is lead or unknown
• You have an infant, a young child, or a pregnancy in the household and want the drinking supply addressed
• Your area has had public reporting about PFAS in the water supply and you want to understand your position
• You live near a site with a known history of firefighting foam use, industrial discharge or certain manufacturing
• Your utility has issued a notice about either contaminant and you are deciding what, if anything, to do at home
• You are buying a house and want to know what the plumbing between the main and the tap is made of

Seeing something not on this list? Browse water treatment problems by symptom →

How lead and pfas filtration actually works

1. 1

   Find out what your service line is made of

   Your water utility can tell you what it has on record for your address, and many now publish service-line material inventories. The portion inside your property boundary is often your responsibility and may be a different material from the utility side.

   Watch forAn "unknown" record being read as "not lead". Unknown means nobody has verified it. Ask your utility how to have it identified, and ask what assistance or replacement programmes exist locally - many places have them.

2. 2

   Read your utility report, and understand exactly what it does not cover

   Your utility's annual water-quality report describes what it delivered, measured at its sampling points. That is genuinely useful information, and it is free.

   Watch forTreating compliance at the utility as an answer about your tap. For lead specifically it cannot be, because the metal is usually picked up between the main and your glass - in the service line, in old solder, in brass fittings. This single point is the reason lead is a household question rather than a utility question.

3. 3

   Test at your own tap, through a certified laboratory

   For lead, sampling protocol is decisive: first-draw samples after water has sat still behave very differently from flushed samples, and each answers a different question. Your health department or a state-certified lab will tell you which protocol to use for your purpose. Our testing page covers finding a certified lab.

   Watch forRunning the tap before sampling because it seems more hygienic. On a lead test that can flush away the very thing you are looking for and hand you a reassuring number that describes nothing.

4. 4

   Take the result to a public health authority for interpretation

   Whether a measured value is a concern, and what to do about it, is a public-health judgement. Both the applicable federal framework and many state rules for these contaminants have been actively changing, and the current position is best obtained from EPA, your state health department or your utility directly rather than from any article.

   Watch forAny website or salesperson quoting you a threshold with confidence. These numbers move, they differ between federal and state levels, and being out of date about them is worse than being silent. We are deliberately not stating any here.

5. 5

   Judge a product only by contaminant-specific certification

   Independent certification is granted for a named contaminant against a named standard. That means a product can be legitimately certified for chlorine taste and odour, or for particulate reduction, and hold no certification whatsoever for lead or PFAS - while being sold in a way that lets you assume otherwise.

   Watch forThe words "filters lead" or "reduces PFAS" with no certifying body and no standard named beside them. That is a marketing claim, not a verified performance statement. Ask which certifier, which standard, which contaminant, and check it on the certifier's own listing rather than the seller's page.

6. 6

   Choose point of use for drinking water

   For both contaminants the practical domestic approach is treating the water you drink and cook with, at the tap, rather than the entire building. Certified point-of-use options are far more widely available, far cheaper, and easier to maintain properly than whole-house alternatives.

   Watch forBeing sold a whole-house system for a drinking-water contaminant. For lead in particular, treating at the point of entry does nothing about metal picked up in the household plumbing downstream of the treatment.

7. 7

   Maintain it as if the certification depends on it, because it does

   Certified performance is stated over a defined capacity. Past that point the certification simply does not describe the cartridge in your cupboard any more, and there is no visible or tasteable warning.

   Watch forRunning cartridges past their rated capacity because the water still tastes fine. Taste is not the mechanism for either of these contaminants - neither has a taste - so it tells you nothing at all about whether the filter is still performing.

8. 8

   Verify by test, and keep the practical habits

   A post-installation lab test at the treated tap is the proof. Alongside it, the standard advice from health authorities is worth keeping: run the tap before drinking after long stagnation, use cold water for drinking and cooking, and clean aerators periodically.

   Watch forSubstituting habits for treatment or treatment for habits. Your health department will tell you which combination fits your actual result - that conversation is free and it is the right place for it.

What does lead and pfas filtration cost?

Certified point-of-use options for drinking water range from tens of dollars for a pitcher or faucet-mounted unit to several hundred or more for an under-sink system installed. Whole-house approaches cost considerably more and are rarely the right answer for these contaminants. Replacement cartridges are the recurring cost and the certification depends on changing them.

See the full lead and pfas filtration cost guide - by material, size and region →

If the number is the problem, here are the ways people pay for it →