Analysis of Perfluorinated Alkyl Acids Specified in EPA M537 and Beyond in Drinking Water Using Triple Quadrupole LC/MS/MS System.

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1 Analysis of Perfluorinated Alkyl Acids Specified in EPA M537 and Beyond in Drinking Water Using Triple Quadrupole LC/MS/MS System. Brahm Prakash 1 Tairo Ogura 1,Jerry Byrne 1 and William Lipps 2 1.Shimadzu Scientific Instruments, Inc., Columbia MD USA 2.Eurofins Eaton Analytical, Inc., Monrovia CA USA August 9,

2 Per- and Polyfluoroalkyl Ether Acids (PFAS) in Drinking Water Sources and Finished Drinking Water: Brief Environmental Background 6) 2

3 What are Per- and Polyfluoroalkyl Ether Acids (PFAS)Substances 3

4 PFAS Environmental Occurrence Examples 4

5 EPA Method 537: Lowest Concentration Minimum Reporting Level (LCMRL) was Determined from multiple Labs in Initial Method Validation Study for 14 Analytes Analyte LCMRL (ng/l) PFBS 3.7 PFHxA 2.9 PFHpA 3.8 PFHXxS 8 PFOA 5.1 PFNA 5.5 PFOS 6.5 PFDA 3.8 NMeFOSAA 14 NEtFOSAA 14 PFUnA 6.9 PFDoA 3.5 PFTrDA 3.8 PFTA 4.7 5

6 MRLs (minimum reporting levels) from Multiple Labs in Initial Method Validation (2008) - EPA M537 6

7 Health Effects of PFAS Compounds 7

8 Current Updates On PFAS from USEPA Office of Water (OW) 8

9 Analytical Methods: PFAS Current LC-MS/MS Methods Available Method EPA 537 ASTM D7968 (Needs Multi Labs Validation study) ASTM D7979 (Needs Multi Labs Validation study) Analytes 14 targets 3 surrogates 3 ISTDs 21 targets 9 surrogates 21 targets 9 surrogates Sample materials Drinking water Soil Sludge, Influent, Effluent and Wastewater Sample prep SPE Dilution w/ MeOH Extraction w/ H 2 O:MeOH Injection vol. 10 μl injection 30 μl injection 30 μl injection Min Reporting Level 5.1 ng/l (PFOA) 10 ng/l (PFOA) 10 ng/l (PFOA) Shimadzu TQ (Triple Quad LCMS) 8045/ / /8060 9

10 LC-MS/MS Methods Recognized by EPA Method EPA M537 M8327 Analytes Sample materials Sample prep 14 targets 3 surrogates 3 ISTDs Drinking water SPE 37 targets 3 surrogates 3 ISTDs Groundwater, Surfacewater, Influent, Effluent and Wastewater Extraction w/ H 2 O:MeOH EPA SW-846 method Shimadzu has been involved in round robin. Injection vol. 10 μl injection 30 μl injection Min Reporting Level 5.1 ng/l (PFOA) 10 ng/l (PFOA) 10

11 Shimadzu Instrumentation Used to Conduct M537 PFAS Studies LCMS

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13 Standard Stability Study: Glass Vials Vs Polypropylene Vials 10% Methanol 90% water and 30% Methanol 70% water 13

14 Standard Stability Study Glass Vials Vs Polypropylene Vials 50% Methanol 50% water and 90% Methanol 10% water 14

15 Excessive Methanol Effect 3.0 (x10,000) ul 20 ul min 10 ul 30 ul 15

16 PFAS: Floating Effect 16

17 PFAS : Sample Vials Vortex Effect 17

18 PFAS Analysis: Optimized Instrument Method Conditions 18

19 Target List Including Newly Added Compounds To M537 List - Internal Standards and Surrogates Used as per EPA M537 1 PFBA > PFPeA > PFBS > > FTS > > PFHxA > > PFPeS > > PFHpA > > PFHxS > > FTS > > PFOA > > PFHpS > > PFOS > > PFNA > > FTS > > PFNS > > PFDA > > N-MeFOSAA > > N-EtFOSAA > > PFDS > > PFUnA > > PFDoA > > PFTrDA > > PFTA > > MPFHxA_Surr > M2PFOA_IS > MPHOS_IS > MPFDA_Surr > N-MeFOSAA_IS > MN-EtFoSAA_Surr >

20 Isolator or Delay Column To Overcome Background Contamination (x10,000) m in (x10,000) m in 20

21 PFAS Analysis: Chromatograms: Null blank, Laboratory Reagent blank and Extracted blank for EPA M537 Using Shimadzu LCMS

22 PFAS Analysis : Chromatogram for PFASs fortified at 20 ng/ml for EPA M537 Using Shimadzu LCMS

23 PFAS Analysis : Chromatogram for PFASs fortified at 20 ng/ml for EPA M537 Using Shimadzu LCMS (x1,000,000) min 23

24 Chromatogram and Calibration curve Method EPA 537 Using LCMS

25 MDL s M537 Vs Shimadzu LCMS-8045 and LCMS

26 MRL validation for M537- Shimadzu LCMSMS

27 Results from Initial Calibration and repeat injections LCMS-8045: System Stability 27

28 Precision and Accuracy Study Results LCMS-8045 and LCMS

29 Precision and Accuracy Study Results LCMS

30 Summary and Conclusions 30

31 Method Development on PFCs Continues 31