Detecting PFAS in water requires highly sensitive laboratory techniques capable of identifying trace concentrations, often measured in parts per trillion (ppt). To standardize testing nationwide, the U.S. Environmental Protection Agency (EPA) has developed several approved analytical methods.
EPA Method 537.1 and EPA Method 533 are the primary procedures used to test for PFAS in drinking water.
Method 537.1 targets 18 long-chain PFAS compounds, including PFOA and PFOS, using solid-phase extraction (SPE) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS).
Method 533, released in 2019, complements it by focusing on 25 short-chain PFAS compounds that earlier methods missed.
Together, these two methods provide a comprehensive snapshot of PFAS contamination in public water systems.
For non-drinking water samples, like wastewater, groundwater, and surface water, EPA Method 1633 represents the next generation of PFAS testing. Still under validation but widely used in pilot programs, Method 1633 detects 40 different PFAS using ultra-sensitive LC-MS/MS technology. It is designed to support future regulatory enforcement and expand PFAS monitoring beyond drinking water.
Laboratories performing these tests must follow strict quality assurance procedures, including field blanks, calibration checks, and chain-of-custody protocols to avoid contamination, since PFAS are so ubiquitous they can even leach from lab gloves or tubing.
Through these standardized methods, scientists and utilities can identify PFAS contamination accurately, compare results nationally, and track progress toward cleaner water.
PFAS contamination is not confined to one region, it’s a nationwide issue affecting urban, suburban, and rural areas alike. Testing data from 2020–2025 reveals distinctive regional patterns tied to industrial history, military installations, and population density.
These states have among the highest PFAS detection rates, largely due to dense manufacturing zones and early industrial use. New Jersey and New York were among the first to set state-level PFAS limits after identifying widespread contamination in public wells and reservoirs.
Michigan emerged as an early leader in PFAS monitoring after discovering extensive contamination from plating facilities and firefighting foams. The state’s “MPART” program has tested thousands of water systems, identifying hundreds with detectable PFAS levels.
North Carolina’s Cape Fear River region gained national attention when PFAS from the Chemours plant contaminated drinking water for over 200,000 residents. Similar discoveries across the South have led to tighter state oversight.
California’s large-scale testing of public systems revealed PFAS in more than 60% of sampled locations. Colorado and Washington continue to address legacy contamination near military bases and airports.
Across all regions, PFAS levels vary widely, from nondetectable in remote wells to over 1,000 ppt in industrial zones. These results highlight the importance of continuous testing and public transparency to inform both policy and cleanup efforts.
Between 2020 and 2025, PFAS testing has expanded from limited pilot studies to a nationwide environmental initiative. Several key trends define this era of PFAS monitoring:
Increased Federal Oversight
Advanced Detection Technologies
Data Transparency
Industry Accountability
Shift Toward Prevention
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