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Using NIST Standard Reference Materials to Validate a Method For Using NIST Standard Reference Materials to Validate a Method for the Detailed Analysis of Polycyclic Aromatic Hydrocarbons in Environmental Matrices on a New GC Column Phase Christopher Rattray, Jack Cochran EPA 16 PAH Acenaphthene Acenaphthylene Benzo[a]pyrene Anthracene Benz[a]anthracene Chrysene Benzo[b]fluoranthene Benzo[k]fluoranthene Benzo[ghi]perylene Dibenz[a,h]anthracene Fluoranthene Indeno[1,2,3-cd]pyrene Naphthalene Fluorene Phenanthrene “Although the HPLC conditions described allow for a unique resolution of the specific PAH compounds covered by this Pyrene method, other PAH compounds may interfere.” EPA Method 610 6.2.6 - The extent of interferences that may be encountered using GC/MS techniques has not been fully assessed. Although GC conditions described allow for unique resolution of the specific PAH compounds covered by this method, other PAH compounds may interfere. Method TO-13A 11.6.1.4 - Structural isomers that produce very similar mass spectra should be identified as individual isomers if they have sufficiently different gas chromatographic retention times. Sufficient gas chromatographic resolution is achieved if the height of the valley between two isomer peaks is less than 50% of the average of the two peak heights. Otherwise, structural isomers are identified as isomeric pairs. The resolution should be verified on the mid-point concentration of the initial calibration as well as the laboratory designated continuing calibration verification level if closely eluting isomers are to be reported (e.g., benzo(b)fluoranthene and benzo(k)fluoranthene). Method 8270D Chrysene Triphenylene Rxi-5Sil MS Rxi-5ms m/z = 226.00 m/z = 228.00 Benzofluoranthenes and Benzopyrenes by EPA Method 8270 (split) on the Rxi-5ms m/z = 252.00 2 ng/mL 8270 mix m/z = 252.00 NIST SRM 1941a extract Additional PAH “Critical Peak Couples” Benz[a]anthracene Phenanthrene Benzo[b]fluoranthene Benzo[a]pyrene Triphenylene Per NF ISO 28540, PAHs are considered resolved when the peak valley height relative to the highest peak (X/Y * 100%) is less than 25% Benzo[k]fluoranthene Anthracene Benzo[e]pyrene Chrysene NIST SRM 1941b Extract on the 30m Rxi-PAH Elemental Sulfur m/z 160, 192 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 24.00 Benz[a]anthracene Chrysene m/z = 228.00 triphenylene 9.85 9.90 9.95 10.00 10.05 10.10 10.15 10.20 10.25 10.30 10.35 10.40 10.45 m/z = 252.00 Benzofluoranthenes [B] [K] [J] 13.90 13.95 14.00 14.05 14.10 14.15 14.20 14.25 14.30 14.35 Dibenz[ah]anthracene – suspected coelution m/z = 278.00 18.80 18.90 19.00 19.10 19.20 19.30 19.40 19.50 19.60 naphthalene 2-methylnaphthalene 1-methylnaphthalene biphenyl 2,6-dimethylnaphthalene acenaphthylene acenaphthene 2,3,5-trimethylnaphthalene fluorene phenanthrene anthracene Certified NIST SRM 1941B 1-methylphenanthrene fluoranthene pyrene Experimental benz[a]anthracene triphenylene chrysene benzo[b]fluoranthene benzo[k]fluoranthene benzo[j]fluoranthene Method Performance Summary etfe opud 78% Certified Compounds benzo[a]pyrene 106% Compounds All indeno[123-cd]pyrene SRM 1941b (30 m) dibenz[ah]anthracene benzo[ghi]perylene dibenzo[al]pyrene dibenzo[ae]pyrene Recovery dibenzo[ai]pyrene dibenzo[ah]pyrene GC_EV1394 Detailed PAHs on 60m Rxi-PAH 60 m x 0.25 mm ID X 0.10 µm Rxi-PAH 1 µL injection split 10:1 1.95 mL/min He Oven Program (72 minutes) 110 ⁰C (hold 1.6 min) 24 ⁰C/min to 210 ⁰C 1.9 ⁰C/min to 295 ⁰C 3.7 ⁰C/min to 350 ⁰C (hold 6 min) 5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.00 45.00 50.00 55.00 60.00 Chrysene m/z = 226.00 m/z = 228.00 Triphenylene Cyclopenta[cd]pyrene 27.40 27.50 27.60 27.70 27.80 27.90 28.00 28.10 m/z = 252.00 Benzofluoranthenes B K J A 38.00 38.20 38.40 38.60 38.80 39.00 39.20 39.40 39.60 m/z = 276.00 10000 Indeno[123-cd]pyrene m/z = 278.00 Dibenz[ah]anthracene 9000 8000 7000 6000 5000 Dibenz[ac]anthracene 4000 3000 2000 1000 0 52.60 52.70 52.80 52.90 53.00 53.10 53.20 53.30 SRM 1975 on the 60m Rxi-PAH (72 minutes) 5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.00 45.00 50.00 55.00 60.00 65.00 NIST SRM 1975 Method Performance Summary SRM 1975 (72 min) Recovery Certified Compounds 103% Reference Compounds 142% AllCompounds 122% Certified Experimental Name Amount (µg/g) SRM (µg/g) Recovery indeno[123-cd]pyrene 0.090 0.1596 57% dibenz[ac]anthracene 0.67 0.10507 638% dibenz[ah]anthracene dibenz[al]pyrene 0.068 0.03591 189% coronene 0.90 0.8911 101% m/z = 278.10 m/z = 276.10 Compound interfering with Dibenz[ah]anthracene Dibenz[ah]anthracene Indeno[123-cd]pyrene Dibenz[ac]anthracene Benzo[ghi]perylene Dibenz[aj]anthracene 49.00 50.00 51.00 52.00 53.00 54.00 55.00 56.00 57.00 GC_EV1395 1941b on 60m Rxi-PAH 450000 400000 350000 300000 250000 200000 150000 100000 50000 Elemental Sulfur m/z 160, 192 5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.00 45.00 50.00 55.00 60.00 naphthalene 2-methylnaphthalene biphenyl acenaphthylene acenaphthene fluorene phenanthrene anthracene fluoranthene pyrene benzo[c]phenanthrene benz[a]anthracene Certified triphenylene NIST SRM 1941B chrysene benzo[b]fluoranthene benzo[k]fluoranthene Experimental benzo[j]fluoranthene benzo[a]fluoranthene benzo[e]pyrene benzo[a]pyrene perylene dibenz[aj]anthracene eeec opud 56% Reference Compounds dibenz[ac]anthracene Method Performance Summary etfe opud 78% Certified Compounds indeno[123-cd]pyrene 71% Compounds All dibenz[ah]anthracene SRM 1941b (60 m) benzo[ghi]perylene benzo[b]chrysene picene dibenzo[al]pyrene dibenzo[ae]pyrene Recovery dibenzo[ai]pyrene dibenzo[ah]pyrene 45 Native PAHs + 6 Deuterated Internal Standards PAHs on the Rxi-PAH and 1 Deuterated Extraction Surrogates 60 m x 0.25 mm ID X 0.10 µm Rxi-PAH 1 µL injection split 10:1 1 mL/min He Oven Program (96.2 minutes) 110 ⁰C (hold 1.6 min) 30 ⁰C/min to 175 ⁰C 1.6 ⁰C/min to 265 ⁰C 4.0 ⁰C/min to 350 ⁰C (hold 15 min) 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 m/z = 226.00 PAHs on the Rxi-PAH m/z = 228.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 m/z = 252.00 Benzofluoranthenes on the Rxi-PAH 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 m/z = 276.00 Dibenzo Anthracenes on the Rxi-PAH m/z = 278.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 m/z = 300.00 Dibenzopyrenes on the Rxi-PAH m/z = 302.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 TIC: NIST SRM 1975 GC-MS SIM 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 NIST SRM 1975 Method Performance Summary SRM 1975 (92 minutes) Recovery Certified Compounds 106% Reference Compounds 82% AllCompounds 94% Certified Experimental TIC: NIST SRM 1597a (diluted 50:1) GC-MS SIM 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 naphthalene 2-methylnaphthalene 1-methylnaphthalene biphenyl 2,6-dimethylnaphthalene acenaphthylene acenaphthene fluorene dibenzothiophene Phenanthrene anthracene 1-methylphenanthrene 4H-cyclopenta[def]phenanthrene fluoranthene pyrene benzo[ghi]fluoranthene Certified benzo[c]phenanthrene NIST SRM 1957A benz[a]anthracene cyclopenta[cd]pyrene triphenylene chrysene Experimental benzo[b]fluoranthene benzo[k]fluoranthene benzo[j]fluoranthene benzo[a]fluoranthene benzo[e]pyrene benzo[a]pyrene perylene dibenz[aj]anthracene dibenz[ac]anthracene Method Performance Summary eeec opud 109% Reference Compounds indeno[123-cd]pyrene 112% Certified Compounds dibenz[ah]anthracene 111% Compounds All benzo[b]chrysene SRM 1597a min)(96 picene benzo[ghi]perylene anthanthrene dibenzo[bk]fluoranthene dibenz[al]pyrene dibenz[ae]pyrene Recovery coronene dibenz[ai]pyrene dibenz[ah]pyrene Questions?.
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