Disclaimer: The PFAS measurements reported here represent initial laboratory findings that have not been subjected to full validation and quality assurance/quality control procedures and should be considered preliminary.
As part of the North Carolina Per and Polyfluoroalkyl Substances Testing (PFAST) Network statewide sampling effort (ncpfastnetwork.com), a raw water sample collected from MARION, CITY OF-1 (NC0156010-1) on 2019-10-09 by the Ferguson Lab was analyzed for 46 PFAS chemicals by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Concentrations of individual PFAS are reported in units of parts-per-trillion (ppt, i.e., nanogram of chemical per liter water).
PFAS compounds are not currently regulated as drinking water contaminants by the United States Environmental Protection Agency (US EPA) or the North Carolina Department of Environmental Quality (NC DEQ) and thus the measurements reported here are not intended to be used in enforcement actions. The US EPA has established a lifetime health advisory level (HAL) of 70 ppt for combined perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in drinking water. In addition, the NC DHHS has established a provisional health goal based on risk assessment for GenX in drinking water of 140 ppt. These advisory levels can serve as reference values when evaluating PFAS concentrations reported below for raw drinking water.
Reporting Limit (RL): This is the lowest concentration that can be confidently quantified in water samples for an individual PFAS chemical. This level is a function of instrument sensitivity, reproducibility, and precision. The RL typically (but not always) represents the lowest concentration point on the calibration curve, and it is always higher (often much higher) than the method detection limit (MDL) for a given PFAS analyte.
PFOA and PFOS were both below their respective reporting limits.
GenX was not detected above its reporting limit.
No PFAS were detected above reporting limits.
Figure 1: Concentrations of individual PFAS compounds.
Table 1 Concentrations of PFAS compounds detected in parts-per-trillion (ppt). Gray values indicate compounds below the reporting limit (RL). Bold rows indicate occurrence in excess of the EPA Health Advisory Limit (HAL) for PFOS + PFOA of 70 ppt.
Analyte Name | Abbreviation | CAS Registry Number | Concentration (ppt) | RL (ppt) |
---|---|---|---|---|
Fluoroalkyl sulfonamides (FASAs) | ||||
Perfluorobutane sulfonamide | PFBSA | 30334-69-1 | <RL | 1 |
Perfluorohexane sulfonamide | PFHxSA | 41997-13-1 | <RL | 1 |
Perfluorooctane sulfonamide | PFOSA | 754-91-6 | <RL | 1 |
N-methyl perfluorooctanesulfonamidoacetic acid | NMeFOSAA | 2355-31-9 | <RL | 1 |
N-ethyl perfluorooctanesulfonamidoacetic acid | NEtFOSAA | 2991-50-6 | <RL | 5 |
Fluorotelomer Sulfonates | ||||
4:2 Fluorotelomer sulfonic acid | 4:2 PFS | 757124-72-4 | <RL | 1 |
6:2 Fluorotelomer sulfonic acid | 6:2 PFS | 27619-97-2 | <RL | 1 |
8:2 Fluorotelomer sulfonic acid | 8:2 PFS | 39108-34-4 | <RL | 1 |
10:2 Fluorotelomer sulfonic acid | 10:2 PFS | 120226-60-0 | <RL | 1 |
Perfluoroalkylcarboxylic acids (PFCAs) | ||||
Perfluorobutanoic acid | PFBA | 375-22-4 | <RL | 1 |
Perfluoropentanoic acid | PFPeA | 2706-90-3 | <RL | 2 |
Perfluorohexanoic acid | PFHxA | 307-24-4 | <RL | 2 |
Perfluoroheptanoic acid | PFHpA | 375-85-9 | <RL | 1 |
Perfluorooctanoic acid | PFOA | 335-67-1 | <RL | 1 |
Perfluorononanoic acid | PFNA | 375-95-1 | <RL | 5 |
Perfluorodecanoic acid | PFDA | 335-76-2 | <RL | 5 |
Perfluoroundecanoic acid | PFUnDA | 2058-94-8 | <RL | 1 |
Perfluorododecanoic acid | PFDoDA | 307-55-1 | <RL | 1 |
Perfluorotridecanoic acid | PFTrDA | 72629-94-8 | <RL | 2 |
Perfluorohexadecanoic acid | PFHxDA | 67905-19-5 | <RL | 10 |
Perfluoroalkylether Acids (PFEAs) | ||||
Perfluoro-2-methoxyacetic acid | PFMOAA | 674-13-5 | <RL | 5 |
Perfluoro-2-methoxypropanoic acid | PMPA | 377-73-1 | <RL | 1 |
Perfluoro(3,5-dioxahexanoic) acid | PFO2HxA | 39492-88-1 | <RL | 1 |
Perfluoro-2-ethoxypropanoic acid | PEPA | 267239-61-2 | <RL | 1 |
1,1,2,2-tetrafluoro-2-(1,2,2,2-tetrafluoro-ethoxy)ethane sulfonic acid | NVHOS | N/A | <RL | 1 |
Perfluoro(3,5,7-trioxaoctanoic) acid | PFO3OA | 39492-89-2 | <RL | 1 |
Perfluoro-2-propoxypropanoic acid | GenX | 13252-13-6 | <RL | 1 |
Perfluoro(3,5,7,9-tetraoxadecanoic) acid | PFO4DA | 39492-90-5 | <RL | 1 |
Dodecafluoro-3H-4,8-dioxanonanoic acid | ADONA | 958445-44-8 | <RL | 1 |
Propanoic acid, 3-[1-[difluoro(1,2,2,2-tetrafluoroethoxy)methyl-1,2,2,2-tetrafluoroethoxy]-2,2,3,3-tetrafluoro- | Hydro-EVE acid | 773804-62-9 | <RL | 1 |
Ethanesulfonic acid, 2-[1-[difluoro[(1,2,2-trifluoroethenyl)oxy]methyl]-1,2,2,2-tetrafluoroethoxy]-1,1,2,2-tetrafluoro- | Nafion by-product 1 | 29311-67-9 | <RL | 1 |
Perfluoro(3,5,7,9,11-pentaoxadodecanoic) acid | PFO5DoDA | 39492-91-6 | <RL | 2 |
Ethanesulfonic acid, 2-[1-[difluoro(1,2,2,2-tetrafluoroethoxy)methyl]-1,2,2,2-tetrafluoroethoxy]-1,1,2,2-tetrafluoro- | Nafion by-product 2 | 749836-20-2 | <RL | 1 |
9-chlorohexadecafluoro-3-oxanonane-1-sulfonate | F-53B (Major) | 73606-19-6 | <RL | 1 |
11-chloroeicosafluoro-3-oxanonane-1-sulfonate | F-53B (Minor) | 83329-89-9 | <RL | 1 |
Perfluoroalkylsulfonic Acids (PFSAs) | ||||
Perfluorobutanesulfonic acid | PFBS | 375-73-5 | <RL | 1 |
Perfluoropentanesulfonic acid | PFPeS | 2706-91-4 | <RL | 1 |
Perfluorohexanesulfonic acid | PFHxS | 355-46-4 | <RL | 2 |
Perfluoroheptanesulfonic acid | PFHpS | 375-92-8 | <RL | 1 |
Perfluorooctanesulfonic acid | PFOS | 1763-23-1 | <RL | 1 |
Perfluorononanesulfonic acid | PFNS | 68259-12-1 | <RL | 1 |
Perfluorodecanesulfonic acid | PFDS | 2806-15-7 | <RL | 10 |
Perfluorododecanesulfonic acid | PFDoS | 79780-39-5 | <RL | 10 |
Zwitterions | ||||
N-(3-dimethylaminopropan-1-yl)perfluoro-1-hexane-sulfonamide | N-AP-FHxSA | 50598-28-2 | <RL | 5 |
N-[3-(perfluoro-1-hexanesulfonamido)propan-1-yl]-N,N,N-trimethylammonium | N-TAmP-FHxSA | 38850-51-0 | <RL | 1 |
N-(carboxymethyl)-N,N-dimethyl-N-[3-(1H,1H,2H,2H-perfluoro-1-octanesulfonamido)propan-1-yl]ammonium | N-CMAmP-6:2FOSA (6:2 FTAB) | 34455-29-3 | <RL | 2 |