Application Note 323. Meets the requirements of U.S. EPA Method 3545

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1 Appliction Note 323 Extrction of Polychlorinted Dienzo-p-dioxins nd Polychlorinted Dienzofurns from Environmentl Smples Using Accelerted Solvent Extrction (ASE) Meets the requirements of U.S. EPA Method 3545 Introduction Regultory gencies re concerned with the high toxicity of polychlorinted dienzo-p-dioxins (PCDDs) nd polychlorinted dienzofurns (PCDFs); gret efforts re expended to monitor their presence in environmentl smples. The low concentrtions t which these compounds re regulted nd the strength of their inding to certin mtrices pose specil chllenges to nlyticl chemists. The most commonly used extrction procedure is Soxhlet extrction. It is time-consuming (typiclly 18 to 36 h) nd requires lrge volumes of solvent (250 to 500 ml). An lterntive method is wrrnted. Accelerted Solvent Extrction (ASE ) is equivlent to U.S. EPA Methods 3540, 3541, nd 8150 for the extrction of orgnochlorine pesticides (OCPs), orgnophosphorus pesticides (OPPs), semivoltiles or se, neutrl, cids (BNA), chlorinted hericides, polycyclic romtic hydro crons (PAHs), nd polychlorinted iphenyls (PCBs). ASE complies with U.S. EPA Method 3545 for these com pounds. ASE is technique tht uses liquid solvents t elevted tempertures nd pressures. These conditions llow extrctions to tke plce in short periods of time with smll solvent volumes s compred to conventionl techniques such s soniction nd Soxhlet extrction. For exmple, 10 grm smple cn typiclly e extrcted y ASE in less thn 15 min with less thn 15 ml of solvent s compred to severl hours nd severl hundred milliliters of solvent with Soxhlet. ASE hs een pplied to the extrction of PCDDs nd PCDFs from ground chimney rick, urn dust, fly sh, nd sediment smples; the results re reported here. EQUIPMENT Dionex ASE 200 Accelerted Solvent Extrctor* Gs chromtogrph (GC) equipped with mss spec trom eter (MS) (low resolution or high resolution MS-MS) Low pressure LC system for smple clenup Preprtive HPLC for smple clenup *ASE 150 nd 350 cn e used for equivlent results. solvents Toluene, pesticide grde Acetic cid, regent grde Hydrochloric cid, regent grde All solvents re ville from Fisher Scientific. smple informtion Two smple sets were investigted: one from Germny tht included chimney rick, urn dust, nd fly sh, nd second from Cnd tht included four sediment smples. A sediment smple (EC-2) contining high ng/kg levels (ppt) of PCDDs nd PCDFs ws otined from the Ntionl Wter Reserch Institute (867 Lkeshore Rod, P.O. Box 5050, Burlington, Ontrio, L7R 4A6, Cnd). A low-level sediment smple (HS-2) ws otined from the Ntionl Reserch Council Institute for Mrine Biosciences (1411 Oxford Street, Hlifx, Nov Scoti, B3H 3Z1, Cnd). Both smples re eing investigted s potentil stndrd reference mterils nd were used s received. Two other sediment smples (Prrots By nd Hmilton Hror) were extrcted. Both hve high levels of coextrctle mterils.

2 EXTRACTION CONDITIONS Tle 1 lists the conditions used for the extrction of the chimney rick nd urn dust y Soxhlet nd ASE. Tle 1. Extrction Conditions for Chimney Brick nd Urn Dust Condition Soxhlet ASE* Smple Size 4 10 g 4 10 g Solvent Toluene, 250 ml Toluene, 15 ml Temperture <111 C 150 C Pressure Atmospheric 1500 psi** Time 18 h 5 min het-up, 5 min sttic Anlyticl GC-MS GC-MS *Duplicte extrctions were performed on ech smple nd re totled in the results. **Pressure studies show tht 1500 psi is the optimum extrction pressure for ll ASE pplictions. The procedure for the extrction of fly sh ws slightly different thn the procedure for the other mtrices. Before solvent extrction, the smples were treted with 6 M HCl for 30 min nd then rinsed thoroughly with distilled wter. The extrctions y oth Soxhlet nd ASE were then per formed s listed in Tle 1. One dditionl set of ex trc tions ws performed on fresh fly sh smples. Insted of pretretment with HCl, (5% (v/v) glcil cetic cid ws dded to the toluene for the ASE extrction. All other conditions were held constnt. The extrction conditions for the sediment smples were chnged slightly from those used for the chimney rick nd urn dust. Insted of doing two seprte extrctions on ech smple nd comining the results, the method ws chnged to hve doule sttic extrction period. With this method, the complete extrction time ws out 17 min, nd with the doule extrctions, the totl time ws close to 22 min. All other conditions were identicl to those listed in Tle 1. QUANTITATION Smple Clenup Clenup of the chimney rick, urn dust, nd fly sh smple extrcts ws performed y using chromtogrphic column pcked with multiple lyers of silic gel nd lum in, in ccordnce with the Germn method VDI Extrcts from the sediment smples were clened up using dul stge open column chromtogrphy procedure consisting of modified silic nd lumin sttionry phses. Smples were further clened up using n utomted HPLC cron-sed method to remove diphenylether interferences. Complete detils of the nlyticl procedure re ville elsewhere. 1 Anlysis y GC/MS nd GC/MS/MS Extrcts of the chimney dust, urn dust, nd fly sh smples were nlyzed y GC-LRMS The column used for the chromtogrphy ws 60 m 0.25 mm i.d µm film thickness Dioxin column. Sediment smple extrcts were nlyzed y GC/MS/ MS or GC/HRMS. All extrcts were seprted using 60 m 0.25 mm i.d mm film thickness fused-silic cpillry column. Stndrds An internl stndrd solution contining 10 reference compounds including 13 C 12 - CDD ws used for the chimney dust, urn dust, nd fly sh smples. No clenup stndrd ws used. Smples were reconstituted with recov ery stndrd solution (100 µl) contining 13 C 12-1,2,3,4-T 4 CDD t 25 ng/ml. For the sediment smples, stndrd PCDD/PCDF mixtures were prepred from stock solutions otined from either Cmridge Isotope Lortories, Inc. or Wellington Lortories. The internl quntittion stndrd contined C 12-2,3,7,8-sustituted PCDDs nd PCDFs. The com pounds used re those congeners listed in the dt tles. Following extrction, the smples were spiked with clenup stndrd ( 37 C l4 - CDD) in order to differ entite etween losses occurring t the extrction nd clenup stges. Prior to injection, the smples were recon stituted with recovery stndrd solution (10 µl) contin ing 13 C 12-1,2,3,4-T 4 CDD nd 13 C 12 - CDD t 100 pg/µl in nonne. RESULTS AND DISCUSSION Ground Chim ney Brick nd Urn Dust Tles 2 nd 3 show the results from the ground chim ney rick nd urn dust s selected congeners nd s the totl of the isomers. The toxicity equivlent is clcu lted y dding the weighted fctors of ech isomer s toxicity. 2 Extrction of Polychlorinted Dienzo-p-dioxins nd Polychlorinted Dienzofurns from Environmentl Smples Using Accelerted Solvent Extrction (ASE)

3 One is clculted ccording to formul from the North Atlntic Trety Orgniztion (NATO) nd the other is from the Germn helth orgniztion BgVV. As cn e seen, ASE shows equivlency to the Soxhlet method for recovery of these compounds. Fly Ash The results from the extrctions of the fly sh re listed in Tle 4. The units for this smple re µg/kg ecuse the smple ws so highly contminted. ASE results re equiv lent to those from Soxhlet extrctions when the HCl/wter pretretment ws used. Tle 5 shows the dt from the fly sh extrctions when Tle 2. Averge Vlues (ng/kg) from Ground Chimney Brick Comprison of Soxhlet vs. ASE Group Totls Soxhlet (n=1) ASE (n=2) CDD CDD CDD CDD CDD CDF CDF CDF CDF CDF Congeners Soxhlet (n=1) ASE (n=2) CDD CDD CDD CDD CDD CDD CDF ,2,3,7,8(+1,2,3,4,8)-P 5 CDF CDF ,2,3,4,7,8(+1,2,3,4,7,9)-H 6 CDF CDF CDF CDF CDF CDF Toxicity equivlent (NATO) Toxicity equivlent (BgVV) Vlues re corrected for recovery of 13 C-leled surrogtes. Sum of two extrctions of ech smple. Tle 3. Averge Vlues (ng/kg) from Urn Dust Comprison of Soxhlet vs. ASE Group Totls Soxhlet (n=1) ASE (n=2) CDD CDD CDD CDD CDD CDF CDF CDF CDF CDF n.d. (10) n.d. (10) Congeners Soxhlet (n=1) ASE (n=2) CDD CDD CDD CDD CDD n.d. (8) n.d. (8) CDD CDF ,2,3,7,8(+1,2,3,4,8)-P 5 CDF CDF ,2,3,4,7,8(+1,2,3,4,7,9)-H 6 CDF CDF CDF CDF n.d. (2) n.d. (2) CDF CDF n.d. (3) n.d. (3) Toxicity equivlent (NATO) Toxicity equivlent (BgVV) Vlues re corrected for recovery of 13 C-leled surrogtes. n.d.=not detected. Detection limit, in ppt, given in prentheses. Sum of two extrctions of ech smple. Appliction Note 323 3

4 cetic cid ws dded to the toluene for the extrctions y ASE. The results with the cetic cid re little lower thn with the HCl pretretment, ut the recovery is still close to 96% of tht of Soxhlet, mking ASE essentilly identicl to Soxhlet for these compounds. Tle 4. Averge Vlues (µg/kg) from Fly Ash Comprison of Soxhlet vs. ASE (HCl Pretretment) Group Totls Soxhlet (n=1) ASE (n=2) º CDD CDD CDD CDD CDD CDF CDF CDF CDF CDF Congeners Soxhlet (n=1) ASE (n=2) CDD CDD CDD CDD CDD CDD CDF ,2,3,7,8(+1,2,3,4,8)-P 5 CDF CDF ,2,3,4,7,8(+1,2,3,4,7,9)-H 6 CDF CDF CDF CDF CDF CDF Toxicity equivlent (NATO) Toxicity equivlent (BgVV) Vlues re corrected for recovery of 13 C-leled surrogtes. Pretretment with HCl for 30 min followed y wter rinse. Sum of two extrctions of ech smple. High-Level Sediment Smples A comprison of verge results for the Soxhlet nd ASE methods for the high-level sediment smple (EC-2) is presented in Tle 6. The dt compre very fvorly. Discrepncies were found to exist mostly with the group totl dt. For exmple, despite hving found more isomers in the T 4 CDF nd P 5 CDF congener groups with ASE, the totl vlues were lower thn the Soxhletsed dt. Tle 5. Averge Vlues (µg/kg) from Fly Ash Comprison of Soxhlet vs. ASE Group Totls Soxhlet (n=1) ASE c (n=2) CDD CDD CDD CDD CDD CDF CDF CDF CDF CDF Congeners Soxhlet (n=1) ASE c (n=2) CDD CDD CDD CDD CDD CDD CDF ,2,3,7,8(+1,2,3,4,8)-P 5 CDF CDF ,2,3,4,7,8(+1,2,3,4,7,9)-H 6 CDF CDF CDF CDF CDF CDF Toxicity equivlent (NATO) Toxicity equivlent (BgVV) Vlues re corrected for recovery of 13 C-leled surrogtes. Pretretment with HCl for 30 min followed y wter rinse for Soxhlet smples. No HCl pretretment, nd toluene/cetic cid solvent used for ASE smples. c Sum of two extrctions of ech smple. 4 Extrction of Polychlorinted Dienzo-p-dioxins nd Polychlorinted Dienzofurns from Environmentl Smples Using Accelerted Solvent Extrction (ASE)

5 These differences my e ttriutle to smple heterogeneity. The surrogte recoveries for the two tech niques (verged over the entire dt set) were 78% with Soxhlet nd 70% using ASE. Losses rising from the clenup processes were predictly the sme (54% verge clenup stndrd recovery for the Soxhlet dt nd 63% for the ASE dt). The comprison of the recovery of the specific congeners s shown in Tle 6 is very good. The dt for smple HS-2 show similr trends (Tle 7). The specific congeners re once gin in excellent greement for the two techniques, ut the group results y ASE re lower thn those y Soxhlet. Averge surrogte recoveries were 75% using Soxhlet nd 73% using ASE. Clenup stndrd recoveries were 56% (Soxhlet) nd 66% (ASE). Tle 6. Averge Vlues (ng/kg) from EC-2 Comprison of Soxhlet vs. ASE Group Totls Soxhlet Extrction (n=10) Accelerted Solvent Extrction (n=2) Vlue % RSD Isomers Vlue % RSD Isomers CDD CDD CDD CDD CDD CDF CDF CDF CDF CDF Congeners Vlue % RSD % Recovery Vlue % RSD % Recovery CDD CDD CDD CDD CDD CDD CDF CDF CDF CDF CDF CDF CDF CDF CDF Vlues re corrected for recovery of 13 C-leled surrogtes. Refers to recovery of corresponding 13 C-leled surrogte. Mximum possile concentrtion due to potentil chromtogrphic overlp. Appliction Note 323 5

6 Highly Contminted Sediment Smples The ASE technique ws lso evluted with two sediment smples contining high levels of coextrctles nd oil (Tle 8). Aliquots of these smples were tken from lrger continer s qun tit tively s possile ut were not nerly s homogeneous s the rigorously prepred reference mterils. Recoveries were outside of control limits (25 to 150%) for T 4 CDF nd P 5 CDF Hmilton Hror ASE dt, Tle 7. Averge Vlues (ng/kg) from HS-2 Comprison of Soxhlet vs. ASE Group Totls Soxhlet Extrction (n=4) Accelerted Solvent Extrction (n=2) Vlue % RSD Isomers Vlue % RSD Isomers CDD CDD CDD CDD CDD CDF CDF CDF CDF CDF Congeners Vlue % RSD % Recovery Vlue % RSD % Recovery CDD n.d. (1) 62 n.d. (1) 71 CDD n.d. (1) 75 CDD CDD CDD CDD CDF CDF CDF CDF CDF CDF CDF n.d. (1) 83 n.d. (1) CDF CDF n.d.=not detected. Detection limit, in ppt, given in prentheses. Vlues not used for sttisticl clcultions. Vlues re corrected for recovery of 13 C-leled surrogtes. Refers to recovery of corresponding 13 C-leled surrogte. Mximum possile concentrtion due to potentil chromtogrphic overlp. 6 Extrction of Polychlorinted Dienzo-p-dioxins nd Polychlorinted Dienzofurns from Environmentl Smples Using Accelerted Solvent Extrction (ASE)

7 which likely ccounts for the differences in these dt points when compred to the Soxhlet extrction. Similr differences in the group totl dt were oserved for the Prrots By smples (e.g., T 4 CDF), ut no recoveryrelted prolems were oserved in this cse. Generlly, the dt compre fvorly etween ASE nd Soxhlet for the recovery of PCDDs nd PCDFs from these hevily contminted sediments. Recommended ASE Conditions for PCDDs nd PCDFs Bsed on the results of these experiments, the conditions listed in Tle 9 re recommended for the extrction of polychlorinted dienzo-p-dioxins nd polychlorinted dienzofurns. The conditions my hve to e djusted slightly to optimize extrction efficiency depending on the smple. Incresing the temperture would e the first prmeter to chnge; incresing the extrction time would e next. Tle 8. Averge Vlues (ng/kg) from Highly Contminted Sources Comprison of Soxhlet vs. ASE Group Totls Hmilton Hror Prrots By Soxhlet ASE Soxhlet ASE CDD CDD CDD CDD CDD CDF CDF CDF CDF CDF Congeners CDD CDD CDD CDD CDD CDD CDF CDF n.d. (20) 9.8 CDF CDF CDF n.d. (20) 15 CDF CDF n.d. (2) n.d. (1) CDF CDF Vlues re corrected for recovery of isotopiclly leled surrogte stndrds. n.d.=not detected. Detection limit, in ppt, given in prentheses. Superscripts indicte the numer of isomers detected. Recoveries outside the rnge 25% to 150%; results re not to e used for regultory complince purposes. Mximum possile concentrtion due to potentil chromtogrphic overlp. Appliction Note 323 7

8 CONCLUSIONS The dt show tht ASE is essentilly equivlent to clssicl extrction procedures such s Soxhlet for the extrction of PCDDs nd PCDFs from environmentl mtrices. As n extrction technique, ASE shows gret promise ecuse it cn e pplied to wide vriety of compound clsses. In ddition to eing equivlent to Soxhlet, ASE cn e performed in frction of the time ( totl of 22 min compred to 18 h) nd with much less solvent (15 ml compred to 250 ml). Tle 9. Recommended Conditions for ASE Extrction of PCDDs nd PCDFs Solvent Toluene or toluene/cetic cid (5%, v/v) if HCl pretretment currently used Temperture C Pressure 13.8 MP (2000 psi) Sttic Time 5 15 min Flush Volume 60 70% Purge Time s Numer of Sttic Cycles 2 or 3 ACKNOWLEDGMENTS The contriutions of Dvid S. Wddell, Terez Gorn, nd Vin Khurn from the Ontrio Ministry of Environment nd Energy, Ontrio, Cnd, nd of Dr. Scheutwinkel nd Dr. Mttult from Dr. Scheutwinkel GmH, Berlin, Germny re cknowledged. REFERENCES 1. The Determintion of Polychlorinted Dienzop-dioxins nd Dienzofurns in Soil nd Sediment y GC-MS ; Method E3151B; Ontrio Ministry of Environment nd Energy: ASE is registered trdemrk of Dionex Corportion. TSQ is registered trdemrk of Finnign Corportion. Speed Simplicity Solutions Dionex Corportion North Americ Europe Asi Pcific 1228 Titn Wy U.S./Cnd (847) Austri (43) Benelux (31) ; (32) P.O. Box 3603 Denmrk (45) Frnce (33) Germny (49) South Americ Sunnyvle, CA Irelnd (353) Itly (39) Sweden (46) Brzil (55) Switzerlnd (41) United Kingdom (44) (408) Austrli (61) Chin (852) Indi (91) Jpn (81) Kore (82) Singpore (65) Tiwn (886) LPN PDF 4/ Dionex Corportion