Posted on Feb 7, 2024
The EPA has published two final analytical methods for PFAS: Method 1633 and Method 1621. These new analytical methods are a result of a multi-lab validation led by the Department of Defense (DOD) and done in close collaboration with EPA. They provide laboratories, agencies, and other organizations with standardized procedures for the collection and detection of 40 PFAS compounds of a wide range of PFAS sample types.
Method EPA 1633 has been validated to test for PFAS compounds in groundwater, wastewater, surface water, soil, solids, biosolids, sediments, landfill leachate, and fish tissue. Method 1621 measures the aggregate concentration of organofluorines (molecules with a carbon-fluorine bond) in wastewater by combustion ion chromatograph (CIC).
As stated in the EPA official document, “the method is “performance-based,” which means that modifications may be made without additional EPA review to improve performance (e.g., overcome interferences, or improve the sensitivity, accuracy, or precision of the results) provided that all performance criteria in this method are met.” As also stated in EPA 1633, “The use of two stacked SPE cartridges, the first containing the WAX sorbent and the second containing activated carbon, or other cartridge configurations may be employed in place of the use of the loose carbon described above. However, each laboratory seeking to apply such an approach must document their specific approach and demonstrate its effectiveness in meeting the QC specifications of this method, as described in Sec. 9.1.2. “
Phenomenex has demonstrated that the stacked Strata PFAS shows excellent recovery, reduces cost, and provides similar recoveries when using EPA 1633 and slightly improved recoveries for EPA 1621. Strata PFAS is a single cartridge stacked with WAX and GCB. Labs have shown that a single cartridge helps eliminate mistakes by eliminating sample preparation steps without using messy granular activated carbon in a powdered form.
We look forward to working with labs as they validate both methods for future analytical needs. Finally, with our proficiency testing samples, we partner to meet ISO certification requirements.
Related documents
Evaluation of Extraction Options for EPA Method 1633
PFAS Proficiency Testing EPA 1633
EPA 1633 and EPA 1621 methods and multi-laboratory validation study reports can be found at the Clean Water Act Laboratory Methods website.
