PFAS ("forever chemicals") · 2023
PFOS in Washington Dc, DC tap water
Washington Dc, DC's 2023 PFOS measurement is below the federal limit of 4 ng/L (MCL).
The measurement
| Statistic | Value | Federal limit |
|---|---|---|
Average System-wide | 2.1 ng/L | 4 ng/L MCL |
Range System-wide | 3.8 ng/L | 4 ng/L MCL |
Verbatim from Washington Dc, DC's 2023 Consumer Confidence Report — source document ↗
About PFOS
Perfluorooctanesulfonic acid, a PFAS 'forever chemical' once used in firefighting foam and coatings.
Linked to cancer, thyroid disease, and immune effects; the EPA set an enforceable limit of 4 parts per trillion.
People also ask
+Is there PFOS in Washington Dc, DC tap water?
Yes — Washington Dc, DC's 2023 Consumer Confidence Report lists PFOS at 2.1 ng/L. Washington Dc, DC's 2023 PFOS measurement is below the federal limit of 4 ng/L (MCL).
+What's the federal limit for PFOS in drinking water?
The federal MCL for PFOS is 4 ng/L. The EPA enforces this against the regulated reporting statistic (running annual average or 90th percentile), not a single-sample spike.
+What is PFOS?
Perfluorooctanesulfonic acid, a PFAS 'forever chemical' once used in firefighting foam and coatings. Linked to cancer, thyroid disease, and immune effects; the EPA set an enforceable limit of 4 parts per trillion.
+Where does this PFOS measurement come from?
This page reproduces the PFOS entry from the 2023 Consumer Confidence Report published by the Washington Dc, DC water utility — the annual drinking-water report every U.S. utility is required by federal law to publish. The original source document is archived at /water/dc/washington-dc/2023/source.