Contaminant · PFAS

PFEESA in drinking water

CAS 113507-82-7 · EPA record reviewed 2026-09-02

Perfluoro(2-ethoxyethane)sulfonic acid, an ether PFAS.

In focus10,307Systems tested nationwide

Public records. Clearer context.

What the rules say

PFEESA has no federal limit or EPA health reference value.

Read the EPA source for PFEESA.

Across the country

EPA tested 10,307 water systems for PFEESA and found it in 0. Half of the systems that found it measured less than —, and one in ten measured more than —.

EPA's final UCMR 5 occurrence file contains 66,361 PFEESA results from 10,307 systems. 0 results were at or above the minimum reporting level, across 0 systems. Among detections, the median was — and the 90th percentile was —.

Systems with the highest recorded PFEESA results

No system in this dataset has a reported detection or exceedance for this contaminant.

Filters and testing

NSF/ANSI 58 (reverse osmosis)

A standard number by itself is not a contaminant claim. Check the product's current certification listing and performance data sheet for PFEESA or the specific contaminant you want to reduce. A utility-level record is not a test of your own faucet.