The EU Regulates 20 PFAS Compounds. We May Be Down to Two.

Two governments looked at the same class of chemicals and went in opposite directions.

I sell water filtration for a living. So take my read with that in mind. But this one isn't a sales angle — it's a regulatory fork in the road, and it's happening now.

What the U.S. is doing

In April 2024, EPA issued the first national, legally enforceable drinking water limits for PFAS. Four parts per trillion for PFOA and PFOS. Ten ppt for PFHxS, PFNA, and HFPO-DA (GenX). Plus a Hazard Index for mixtures of PFHxS, PFNA, HFPO-DA, and PFBS, per EPA.

Then in May 2025, EPA announced it would keep the 4.0 ppt limits for PFOA and PFOS, extend the compliance deadline for public water systems from 2029 to 2031, and propose rescinding and reconsidering the standards for PFHxS, PFNA, HFPO-DA, and the Hazard Index. EPA has said it intends to move that rulemaking forward on a timeline that runs into 2026 — check EPA's PFAS page for where it currently stands.

Read that again. The mixture rule — the one that accounted for the fact that PFAS don't show up alone — is the part on the chopping block.

What Europe is doing

The EU Drinking Water Directive (EU) 2020/2184 sets a limit of 0.10 µg/L for the "sum of PFAS," defined as a list of specified compounds, and 0.50 µg/L for "PFAS Total." Member State monitoring obligations phase in on a timetable set out in the directive.

These aren't apples to apples. The EU number is a sum across a list of chemicals — 0.10 µg/L works out to 100 parts per trillion in total. The U.S. numbers are per-compound and far lower for the two big ones. On PFOA and PFOS specifically, 4 ppt is the stricter line by a wide margin.

But the philosophy is different. Europe drew a wide net and counted everything in it. The U.S. is narrowing to a short list of individually regulated chemicals and, if the proposal goes through, dropping the tool that handled combinations.

Why an office manager should care

Because PFAS in your building's water don't care which approach won.

A USGS study of tap water sampled between 2016 and 2021 estimated that at least one PFAS compound could be present in roughly 45% of U.S. drinking water samples, with higher detection rates in urban areas and near known sources. And PFAS have been found in the blood of the overwhelming majority of Americans tested through NHANES. ATSDR links exposure to effects including increased cholesterol, changes in liver enzymes, reduced vaccine response in children, and higher risk of kidney and testicular cancer.

Meanwhile, real occurrence data is piling up. Under UCMR 5, every public water system serving 3,300 or more people — plus a sample of smaller ones — had to monitor for 29 PFAS and lithium. Results go into EPA's public, searchable occurrence dataset. Twenty-nine compounds measured. Potentially two regulated.

That gap is the whole story. We now know more about what's in the water than we're required to do anything about.

What I'd actually do

Look up your building's water system in the UCMR 5 dataset. It's free and it's public. If your system reported detections of compounds that may lose their standard, you know something your landlord probably doesn't.

Then decide whether you want your breakroom's water quality to be a function of federal rulemaking or a function of what you installed. Point-of-use filtration doesn't wait for a comment period to close.

I'm not going to pretend the regulatory outcome doesn't matter. It matters enormously for the many millions of people who only get whatever comes out of the municipal tap. But for an office with a budget and a decision to make, the rules were never the ceiling. They're the floor — and right now somebody's moving the floor.