Sampling and Analysis of PFAS in Biosolids and Associated Media, v. 3.2, Aug. 2020
V. 3.2 includes review & updates as of August 11, 2020, including updated list of laboratories.
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Additional Materials
(Updated April 2021)
Updated NEBRA list of laboratories for PFAS analysis, August 2020 (update 16Sep20)
Massachusetts Department of Environmental Protection Residuals Program’s sampling and analysis protocol for PFAS in residuals. Note: As of March 2021, MassDEP has approved the following labs for biosolids PFAS testing: Alpha Analytical, Bureau Veritas Canada, Contest (a Pace Analytical Lab), Enthalpy, Eurofins Lancaster, and Eurofins Test America.
EPA Webpage: Analytical Methods Development & Sampling Guidance
EPA Webinar Slides: Update on PFAS Analytical Methods, July 23, 2020, produced by Biosolids Program, Office of Water
NY State “Guidelines for Sampling & Analysis of PFAS,” Jan. 2020, updated October 2020
Michigan’s sampling guidance (Oct. & Nov. 2018)
PFAS Sampling & Analysis Training - Slides from NEBRA/NHDES Training at Franklin, NH, June 26, 2019
—PFAS: Why we need to pay attention (intro to PFAS & biosolids issue) - Ned Beecher
—PFAS Sampling & Analysis Training - Michael Rainey
NEBRA Sampling & Analysis guidance & templates, to meet new Maine DEP requirements
ITRC fact sheet on sampling & analysis
EPA fact sheet on sampling (September 2018)
NEBRA webinar slides on analyzing PFAS (September 14, 2017)
Analytical methods updates:
(Updated August 11, 2020)
UPDATE ON PFAS ANALYTICAL METHODS - WEBINAR SLIDES, July 23, 2020, by Chris Impellitteri, Marc Mills, and Andy Gillespie, U. S. EPA
Analyzing PFAS in Drinking Water
Analysis of PFAS in drinking water has been well established and achieves detection and reporting limits in the 0.53 - 6.3 parts per trillion (ppt) range. The current established method is Method 537 Revision 1, published November 2018. It has been updated for additional analytes, including GenX and ADONA. Method 537 applies only to drinking water; if it is modified by a lab for analyzing any other matrix (e.g. by including isotope dilution), it is not considered 537 by U. S. EPA.
On December 19, 2019, U. S. EPA announced a complementary method, Method 533, which tests for an additional 11 PFAS in drinking water. It is better than Method 537 Rev. 1 at detecting short-chain PFAS, such as PFBA and PFBS). It uses isotope dilution after solid phase extraction. See Method 533.
Analyzing PFAS in Water Other Than Drinking Water
In June 2019, U. S. EPA released draft Method 8327, a direct injection method under SW-846. It is to be used for non-drinking waters, including wastewaters. It measures 24 PFAS with target quantitation limits (detection levels) of 10 ng/L (ppt). Comments were taken in summer 2019; a final rule is still pending as of August 10, 2020. Commenters raised concerns that draft Method 8327 did not use isotope dilution, which is widely used and preferred by U. S. Department of Defense and commercial and academic labs because it achieves lower detection limits. U. S. EPA notes that Method 8327 is simpler and more robust. If its higher detection limits are adequate, it can be performed more quickly, maximizing lab throughput and minimizing sample transfer, extractions, filtering, and chemical additions. NEBRA notes that this could make it a less expensive method for routine use, if customers demand it of laboratories.
A direct injection method for PFAS in non-drinking waters - on which draft Method 8327 is based – was established in 2015 and is available from ASTM. See ASTM Standard D7979-15, “Standard Test Method for Determination of Perfluorinated Compounds in Water, Sludge, Influent, Effluent and Wastewater by Liquid Chromatography Tandem Mass Spectrometry (LC/MS/MS)”, 18pp., 2015.
Analyzing PFAS in Solids, Soils, Biosolids, Residuals, Sediments
U. S. EPA was working on a separate method (8328) for solids. But as of spring 2020, it is working with the Department of Defense (DoD) on a method that will fall under EPA’s SW-846 and Clean Water Act programs, while also meeting DoD requirements. This new method, being called CWA-1600, will use isotope dilution, covers 40 PFAS analytes (including all listed in Methods 537 Rev. 1, 533, and 8327), has target quantitation limits of 1 - 10 ng/L, and will be similar to the “modified Methods 537” that most commercial labs are using for a wide variety of matrices. It will cover non-potable water (e.g. wastewater, landfill leachate, etc.), as well as solids (e.g. soils, sediments, biosolids). It will be more robust for complex matrices, according to U. S. EPA. As of August 10, 2020, it is undergoing single lab validation through December 2020. If that is successful, multi-lab validation will follow over 2021, according to U. S. EPA.
A direct injection method for PFAS in soils and solids is available from ASTM. It has relatively high detection limits and is not offered by most commercial laboratories. But it could useful for screening purposes.
TOF: Total Organic Fluorine Method
U. S. EPA considers development of this analysis a high priority, as of July 2020, because it can be a useful, quick screening tool for identifying the presence or absence of total PFAS. A draft method is expected in late 2020 or in 2021. This method uses combustion and ion chromatography to measure total fluorine bonded to carbon (organic fluorine); inorganic fluorine is removed before analysis. The method will measure the total mass of all fluorine in all fluorine-carbon compounds, including more complex PFAS, in addition to well-known PFAS. It does not identify individual compounds.
TOP: Total Oxidizable Precursors Method
This method, developed and published by Houtz et al., has not had multi-lab validation, but it is available from some commercial labs. It does not identify individual PFAS precursors, but it ensures they are broken down (oxidized) to their stable end products, e.g. PFAAs. Each sample must be run through two standard PFAS analyses - once before and once after the oxidation process. The difference between the two results indicates the mass of the PFAA, etc. precursors.