Per- and Polyfluoroalkyl Substances (PFAS):
Reviewing Analytical Methods Data for Environmental Samples
Tips for reviewing LC/MS/MS data generated from PFAS analytical methods
Technical BRIEF
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INNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE
Background
Interpreting data from analysis of per- and polyfluoroalkyl
substances (PFAS) in a variety of environmental sample
types can be challenging due to variations in analytical
protocols, quality control types and criteria, and data
review procedures across laboratories. Analytical chemistry
reference methods, both prescriptive and performance-
based, are available for laboratories to use as a basis to
create standard operating procedures (SOPs) to test for
these chemicals; however, results can be difficult to assess,
compare, and apply to make site-based decisions.
Data reviewers should consider a variety of information
when assessing data quality from liquid
chromatography/tandem mass spectrometry (LC/MS/MS)
analyses, regardless of the method or procedure used.
Data quality reviewers should always defer to site and/or
state specific data review requirements, where available.
Scope of the Review
The level of detail required for the reviewer to adequately
assess data quality will depend on how the data will be
used. For example, site-specific enforcement actions will
generally require a much higher level of scrutiny compared
to pilot-level projects or general screening for site
characterization.
Documentation Needed for Review
Quality Assurance Project Plan (QAPP)
A Quality Assurance Project Plan (QAPP) captures
information that identifies project-specific data quality
objectives (DQOs) and measurement performance criteria,
including analytes and concentration levels of interest and
how the analytical data will be used to achieve any stated
project goals1. The QAPP should be reviewed by data
reviewers and used to determine whether the data
collection effort is successful in achieving project DQOs.
Laboratory Procedures & Quality System Documents
The laboratory's SOPs and other quality systems
documents (e.g., Quality Management Plan) should be
included in the data review to understand how the
laboratory does the following:
•	Maintains sample integrity, including measures to
minimize PFAS contamination during handling and
transport to the laboratory
•	Manages personnel qualifications (e.g., initial
demonstration of capability, or IDOC).
•	Prepares and analyzes samples.
•	Establishes and verifies detection and quantitation
limits [e.g., method detection limit (MDL), limit of
detection (LOD), limit of quantitation (LOQ), etc.]. The
analyst's method for dealing with branched and linear
PFAS isomer detection limits should also be
documented.
•	Assures measurement traceability.
•	Evaluates quality controls (QC) to assess
measurement performance (including QC types,
frequencies, acceptance criteria, and use of second
source PFAS standards for some QC criteria, if
required).
•	Handles out-of-control data, including client
notification and corrective and preventive actions.
•	Reviews data internally prior to release.
•	Performs internal audits.
Laboratories that are accredited to quality systems
standards2 are generally required to have these quality
assurance (QA) elements in place. If the project required
accreditation, the review should verify that the PFAS
analysis (method, media type, analytes) is included in the
scope of the laboratory's accreditation.
U.S. Environmental Protection Agency
EPA/600/F-19/056

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