PFAS ("forever chemicals") · 2025

Perfluorobutanesulfonic acid in Cary, NC tap water

Detected — no federal limit

Cary, NC's 2025 report shows Perfluorobutanesulfonic acid detected, but the EPA has not set an enforceable federal limit for it.

The measurement

StatisticValue
Average
Detection
Not detected
Range
System-wide
0–3.6 ng/L

Verbatim from Cary, NC's 2025 Consumer Confidence Report — source document ↗

About Perfluorobutanesulfonic acid

Perfluorobutanesulfonic acid, a shorter-chain PFAS 'forever chemical.'

Has no standalone limit but is part of the EPA PFAS Hazard Index that limits PFAS in combination.

How Cary, NC compares

5 of the 146 systems measuring Perfluorobutanesulfonic acid on The Water Map have it at or above the federal limit:

Nearby systems also reporting Perfluorobutanesulfonic acid:

People also ask

+Is there Perfluorobutanesulfonic acid in Cary, NC tap water?

Yes — Cary, NC's 2025 Consumer Confidence Report lists Perfluorobutanesulfonic acid at Not detected. Cary, NC's 2025 report shows Perfluorobutanesulfonic acid detected, but the EPA has not set an enforceable federal limit for it.

+What's the federal limit for Perfluorobutanesulfonic acid in drinking water?

The EPA has not set an enforceable federal limit for Perfluorobutanesulfonic acid. Utilities still report any measured levels in their annual Consumer Confidence Report.

+What is Perfluorobutanesulfonic acid?

Perfluorobutanesulfonic acid, a shorter-chain PFAS 'forever chemical.' Has no standalone limit but is part of the EPA PFAS Hazard Index that limits PFAS in combination.

+Which other U.S. cities have Perfluorobutanesulfonic acid over the federal limit?

5 of the 146 systems on The Water Map measuring Perfluorobutanesulfonic acid report it at or above the federal limit. Examples include Gilbert, AZ, Chula Vista Sweetwater, CA, Charleston, SC.

+Where does this Perfluorobutanesulfonic acid measurement come from?

This page reproduces the Perfluorobutanesulfonic acid entry from the 2025 Consumer Confidence Report published by the Cary, NC 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/nc/cary/2025/source.

Full report
All Cary, NC water-quality data →
Every contaminant measured in the 2025 report.
Contaminant pillar
Perfluorobutanesulfonic acid across the U.S. →
Every public water system measuring Perfluorobutanesulfonic acid, ranked.