Laboratory
US EPA PFAS Method 1633
Mar. 24 2022
In September 2021, the United States Environmental Protection Agency (US EPA) issued a draft method for per- and polyfluoroalkyl substances (PFAS) [1]. US EPA Method 1633 is the first PFAS method issued by the US EPA for non-drinking water matrices. Until now, regulated entities and environmental laboratories relied upon modified EPA methods or in-house laboratory standard operating procedures to analyze PFAS in non-drinking water matrices.
Draft EPA Method 1633 is a single laboratory validated method that provides a standardized approach for measuring up to 40 PFAS in a diverse range of environmental matrices including: wastewater, surface water, groundwater, soil, biosolids, sediment, landfill leachate, and fish tissue. This draft method recognizes and incorporates the use of isotope dilution techniques to accurately quantify target PFAS.
Key differences between the draft US EPA Method 1633 and current Bureau Veritas standard operating procedures (based on modified US EPA Methods 537.1 and 533) are highlighted in Table 1 (below). Currently, draft Method 1633 has only been validated by one laboratory. US EPA indicates that a multi-laboratory validation study of draft Method 1633 has begun, and anticipates completion of the study in 2022.
Detailed parameter lists reported are provided in Table 2.
Table 1: Method Comparison between Draft US EPA Method 1633 and Bureau Veritas Standard Operating Procedure CAM SOP-00894/16 (based on a modified US EPA Methods 537.1 and 533.1)
Method Element | Bureau Veritas CAM SOP-00894/16 |
EPA Method 1633 |
---|---|---|
Scope | • Water (incl. drinking water) • Wastewater • Soil • Tissue • AFFF |
• Wastewater • Surface water • Groundwater • Landfill leachate • Soil • Sediment • Biosolids • Tissue |
Sample Collection | Water: 3 x 125 mL HDPE bottles per sample (allowance for QC) Soil: 250mL HDPE jar Tissue: HDPE jar or LDPE zipper sealed bag (size dependent on sample) |
Water: 2 x 500 mL HDPE bottles (per sample) Soil: 500mL HDPE jar; ≤¾ full Tissue: Whole fish, cleaned, filleted or other tissue Allowable sample containers: - HDPE jar (size dependent on sample) - LDPE zip bag - Wrapped in aluminum foil |
Sample Storage and Hold Time | Water: 28 days (at 4° C) Soil: 28 days (at 4° C) Tissue: 28 days (at 4° C) Extracts: 28 days (at 4° C) |
Water: 28 days (frozen at -20° C) 7 days (4° C) Soil: 90 days (frozen at -20° C) Tissue: 90 days (frozen at -20° C) Extracts: 90 days (at 4° C) |
Sample Processing | All samples spiked with isotopically labeled PFAS analogues prior to processing Aqueous: • 125 mL (whole bottle) • pH adjusted to 4-5 Solids: • 4g sample size • Single stage extraction - 70/30 Methanol/Water (0.5% ammonium hydroxide) Tissue: • 4g tissue homogenate • Single stage extraction - 0.01M KOH/Methanol |
All samples spiked with isotopically labeled PFAS analogues prior to processing Aqueous: • 500 mL (whole bottle) • Percent solids determined by filtration of second bottle. • pH adjust to 6.5 ± 0.5 Solids: • 5g sample size • Three stage extraction - 10 mL 0.3% methanolic NH4OH - 15 mL 0.3% methanolic NH4OH - 5 mL 0.3% methanolic NH4OH Tissue: • 2g tissue homogenate • Three stage extraction - 0.05M KOH/Methanol - Acetonitrile - 0.05M KOH/Methanol NH4OH |
Extraction | Solid Phase Extraction (SPE): • Weak anion-exchange (WAX) solid phase extraction • Extract treated with activated carbon cartridge |
Solid Phase Extraction (SPE): • Weak anion-exchange (WAX) solid phase extraction • Concentrated acetic acid and activated carbon added to extract • Extract filtered prior to analysis |
Sample Analysis | Reverse phase LC-MS/MS | Reverse phase LC-MS/MS |
Parameters reported | 32 compounds | 40 compounds |
Typical Reporting Limits | Aqueous: 2.0 – 100 ng/L Solids: 0.1 – 5.0 ug/kg AFFF: 0.80 – 50 ug/L |
Aqueous: 1.6 – 40 ng/L Solids: 0.2 – 5.0 ug/kg Tissue: 0.5 – 12.5 ug/kg |
Year Published | 2020 (ver. 16) | 2021 (DRAFT) |
Notes: Reporting Limit data for US EPA Method 1633 are derived from a single-laboratory validation study and are only provided as examples in this draft method. These will be updated with the pooled reporting limit data from the interlaboratory study results in a subsequent revision.
Table 2: Detailed Parameter Comparison between US EPA Method 1633 and Bureau Veritas Standard Operation Procedure CAM SOP-00894/16 (based on a modified US EPA Method 533.1)
Parameter | Abbreviation | Bureau Veritas CAM SOP-00894/16 |
US EPA Method 1633 |
---|---|---|---|
Perfluorobutanoic acid | PFBA | ✔ | ✔ |
Perfluoropentanoic acid | PFPeA | ✔ | ✔ |
Perfluorohexanoic acid | PFHxA | ✔ | ✔ |
Perfluoroheptanoic acid | PFHpA | ✔ | ✔ |
Perfluorooctanoic acid | PFOA | ✔ | ✔ |
Perfluorononanoic acid | PFNA | ✔ | ✔ |
Perfluorodecanoic acid | PFDA | ✔ | ✔ |
Perfluoroundecanoic acid | PFUnA | ✔ | ✔ |
Perfluorododecanoic acid | PFDoA | ✔ | ✔ |
Perfluorotridecanoic acid | PFTrDA | ✔ | ✔ |
Perfluorotetradecanoic acid | PFTeDA | ✔ | ✔ |
Perfluorobutanesulfonic acid | PFBS | ✔ | ✔ |
Perfluoropentanesulfonic acid | PFPeS | ✔ | ✔ |
Perfluorohexanesulfonic acid | PFHxS | ✔ | ✔ |
Perfluoroheptanesulfonic acid | PFHpS | ✔ | ✔ |
Perfluorooctanesulfonic acid | PFOS | ✔ | ✔ |
Perfluorononanesulfonic acid | PFNS | ✔ | ✔ |
Perfluorodecanesulfonic acid | PFDS | ✔ | ✔ |
Perfluorododecanesulfonic acid | PFDoS | ✔ | |
Perfluorooctanesulfonamide | PFOSA | ✔ | ✔ |
N-methylperfluorooctanesulfonamide | MeFOSA | ✔ | ✔ |
N-ethylperfluorooctanesulfonamide | EtFOSA | ✔ | ✔ |
N-methylperfluorooctanesulfonamidoethanol | MeFOSE | ✔ | ✔ |
N-ethylperfluorooctanesulfonamidoethanol | EtFOSE | ✔ | ✔ |
N-methylperfluorooctanesulfonamidoacetic acid | MeFOSAA | ✔ | ✔ |
N-ethylperfluorooctanesulfonamidoacetic acid | EtFOSAA | ✔ | ✔ |
4:2 Fluorotelomersulfonic acid | 4:2FTS | ✔ | ✔ |
6:2 Fluorotelomersulfonic acid | 6:2FTS | ✔ | ✔ |
8:2 Fluorotelomersulfonic acid | 8:2FTS | ✔ | ✔ |
Hexafluoropropylene oxide dimer acid (GenX) | HFPO-DA | ✔ | ✔ |
4,8-dioxa-3H-perfluorononanoic acid | ADONA | ✔ | ✔ |
9-chlorohexadecafluoro-3-oxanonane-1-sulfonic acid 1 | 9Cl-PF3ONS | ✔ | ✔ |
11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid 2 | 11Cl-PF3OUdS | ✔ | ✔ |
Perfluoro-3-methoxypropanoic acid | PFMPA | ✔ | |
Perfluoro-3-methoxybutanoic acid | PFMBA | ✔ | |
Nonafluoro-3,6-dioxaheptanoic acid | NFDHA | ✔ | |
Perfluoro(2-ethoxyethane)sulfonic acid | PFEESA | ✔ | |
3-Perfluoropropyl propanoic acid | 3:3FTCA | ✔ | |
5:3 Perfluorooctanoic acid | 5:3FTCA | ✔ | |
3-Perfluoroheptyl propanoic acid | 7:3FTCA | ✔ |