Technical BRIEF
INNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE
www.epa.gov/research
Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS)
Methods and guidance for sampling and analyzing water and other environmental media
Background
Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are a
large group of manufactured compounds used in a variety
of industries, such as aerospace, automotive, textiles, and
electronics, and are used in some food packaging and
firefighting materials. For example, they may be used to
make products more resistant to stains, grease, and
water. In the environment, some PFAS break down
slowly, if at all, allowing bioaccumulation (concentration)
to occur in humans and wildlife. Some have been found
to be toxic to laboratory animals, producing reproductive,
developmental, and systemic effects in laboratory tests.
The U.S. Environmental Protection Agency's (EPA)
methods for analyzing PFAS in environmental media are
in various stages of development. EPA is working to
develop validated robust analytical methods for
groundwater, surface water, wastewater, and solids,
including soils, sediments, and biosolids.
Drinking Water
Analysis using EPA Method 537
To assess for potential human exposure to PFAS in
drinking water, EPA-approved commercial drinking water
laboratories successfully analyzed finished (treated)
drinking water samples for six PFAS monitored under the
third Unregulated Contaminant Monitoring Rule
(UCMR3). For the UCMR3 analyses, laboratories used EPA
Method 537, which also includes eight additional PFAS
analytes not listed on the UCMR3.
Health Advisories
In May 2016, EPA issued drinking water health advisories
for two types of PFAS: perfluorooctanoic acid (PFOA) and
perfluorooctanesulfonic acid (PFOS). EPA's health
advisories are non-enforceable and non-regulatory, and
provide technical information to state agencies and other
public health officials on health effects, analytical
methodologies, and treatment technologies associated
with drinking water contamination.
EPA expects to have a draft method for
non-potable water by fall 2018.
Method Development & Validation
Currently, there are no standard EPA methods for
analyzing PFAS in groundwater, surface water,
wastewater, or solids. For non-drinking water samples,
some U.S. laboratories are using modified methods based
on EPA Method 537. These modified methods have no
consistent sample collection guidelines and have not
been validated or systematically assessed for data quality.
EPA formed a cross-Agency method development and
validation workgroup to provide sampling guidance and
validated methods for sample types other than drinking
water, which will fill this sampling and analytical gap. The
workgroup will develop SW-846 analytical methods for
quantifying 24 PFAS analytes. The method development
process will occur in a phased approach.
Phase I
EPA labs tested an existing direct injection
analytical protocol for preparing and analyzing 24 PFAS
analytes in groundwater, surface water, and wastewater.
Labs completed this phase in winter 2017, and results
warranted moving to Phase II. EPA has also drafted a
solid-phase extraction/isotope dilution (SPE-ID) method.
Pending an acceptable Phase I outcome, this method will
be internally validated in spring 2018 for inclusion into
Phase II.
U.S. Environmental Protection Agency
EPA/600/F-17/022b
Updated February 2018

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Phase II
Ten external labs will validate the direct
injection method starting in February 2018. The target
timeframe for publishing a validated SW-846 direct
injection method for public review is fall 2018. Following
the internal validation, the SPE-ID protocol will be
externally validated, with a target for start time in
summer 2018. EPA plans to validate a solids method
(isotope dilution) starting in fall 2018 using a similar
phased approach. Additionally, an analytical method for
short-chained PFAS in drinking water is under
development and planned for external validation and
publication for public review by early 2019.
Developing Sampling & Storage Methods
EPA ran time-based studies on degradation or loss of
target analytes during sample storage (45 days) and
assessed the effects of different sample vessel materials
(e.g., plastic, glass) on analyte recovery. Based on these
studies, the SW-846 methods under development will
utilize PFAS-free, high-density polyethylene containers;
whole sample preparation; and sample holding times of
28 days. EPA will also develop guidelines for field
sampling, which are critical for minimizing sample
contamination and optimizing data quality for site
characterization and remediation.
Due to the widespread use of PFAS, many materials
normally used in field and laboratory operations contain
PFAS. For example, polytetrafluoroethylene products
(tubing, sample containers, and sampling tools) are often
used in sampling; however, since these products can
contain PFAS, they cannot be used in sampling for PFAS.
In addition, many consumer goods, such as water-
resistant jackets or fast food wrappers, brought to a
sampling site may contain PFAS that can contaminate
samples. Proper field sampling and laboratory hygiene
protocols are critical to ensuring that testing results
reflect actual PFAS levels in the analyzed media.
Technical Contacts
•	Chris Impellitteri, impellitteri.christopher(5>epa.gov
•	Schatzi Fitz-James, fitz-iames.schatzi(5)epa.gov
•	Cynthia Caporale, capQrale.cynthia@epa.gov
Communications Contact
•	Michelle Latham, latham.michelle(5)epa.gov
Additional Information
• PFAS in Your Environment:

epa.gov/pfas
Clean-Up Information:
clu-in.org/
• EPA Method 537

nepis.epa.gov/Exe/ZvPDF.cgi?Dockev
P100EQ6W.txt
SW-846 (Compendium):
epa.gov/hw-sw846/sw-846-
comperidium
• Drinking Water Health Advisories
for PFOA and PFOS
epa.gov/ground-water-and-drinking-
water/drinking-water-health-
advisories-pfoa-and-pfos

• Third Unregulated Contaminant
Monitoring Rule (UCMR3)
epa.gov/dwucmr/third-unregulated-
contaminant-monitoring-rule
• EPA's Water Research:
epa.gov/water-research


U.S. Environmental Protection Agency

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