SUPPORTING INFORMATION

Transcription

1 SUPPORTING INFORMATION Aging of Organochlorine Pesticides and Polychlorinated Biphenyls in Muck Soil: Volatilization, Bioaccessibility and Degradation Fiona Wong, Terry F. Bidleman *, Centre for Atmospheric Research Experiments, Science and Technology Branch, Environment Canada, 6248 Eighth Line, Egbert, Ontario, L0L 1N0, Canada Department of Chemistry, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario, M1C 1A4, Canada * Corresponding author terry.bidleman@ec.gc.ca, phone: ; fax: List of SI: Text SI-1 Soil extraction, bioaccessibility, bacterial activity, quantitative analysis and quality control Page S3 Figure SI-1 Air concentration (ng m -3 ) as a function of flow rate (L min -1 ) for muck soil. S5 Figure SI-2 Figure SI-3 Figure SI-4 Figure SI-5 Plateau log K SA of spiked OCs and selected PCBs. Plateau Log K SA for Indoor (IN) ranged from Day 195 to 550, Outdoor (OUT) Day 390 to 730 and Sterile (ST) Day 210 to 550. HPCD extractability of selected OCs and PCBs for Indoor (IN), Outdoor (OUT) and Sterile (ST) soils. Plateau log K SA of native OCs, spike OCs and PCBs vs. log K OA for Indoor, Outdoor and Sterile soils. Plateau log K SA of Indoor soils equals to mean log K SA from Day 195 to 550; Outdoor - from Day 390 to 730; Sterile - from Day 210 to 550. Solid line = log K SA predicted by the modified Karickhoff model. Ln C SOIL of 13 C 6 -α-hch, ENDO I, PCB 8 and 28 over the aging time for Indoor, Outdoor and Sterile soils. Day 60 to 230, 390 to 620 are the winter periods for the Outdoor soils. S6 S7 S8 S9 S1

2 Table SI-1 Mean blanks and limits of detection (LOD) of PCBs in air. S10 Table SI-2 Soil bacteria colony forming units (CFU) for the Indoor, Outdoor and Sterile soils. S11 Table SI-3 Log K SA for the Indoor soils. Plateau is mean log K SA from 195 to 550d. S12 Table SI-4 Log K SA for the Outdoor soils. Plateau is mean log K SA from 390 to 730 d. S13 Table SI-5 Log K SA for the Sterile soils. Plateau is mean log K SA from 210 to 550 d. S14 Table SI-6 Relative K SA of OCs (Spiked/Native). S15 Table SI-7 Indoor plateau log K SA for native OCs compared to literature values obtained from Meijer et al., (2003). Soil from the same farm was used in the Meijer study. S16 Table SI-8 HPCD extractability% for the Indoor soils. S17 Table SI-9 HPCD extractability% for the Outdoor soils. S18 Table SI-10 HPCD extractability% for the Sterile soils. Table SI-11 Half-lives of 13 C 6 -α-hch, endosulfans and PCB 8, 18, 28, 32 for Indoor and Outdoor soils. ns = No significant degradation or degradation does not follow first order kinetics. S19 S20 S2

3 Text SI-1 Soil extraction, bioaccessibility, bacterial activity, quantitative analysis and quality control Soil extraction. C SOIL (ng g -1 dry weight) was obtained by an exhaustive extraction method, using 200 ml DCM, as fraction 1 (F1), in a Soxhlet apparatus for 22 h followed by cleanup with neutral alumina. Sequential Soxhlet extraction of the soil by 50:50 hexane/acetone (F2) and methanol (F3) was performed ensure DCM yields the total extractable fraction. The average 100xF2/F1 and 100 F3/F1 were 11% and 2% respectively, so DCM removed most of the extractable chemicals. Sodium sulfate was extracted as blanks (n=27). Details of the cleanup procedure using alumina chromatography are given in Wong and Bidleman (1). Bioaccessibility and bacterial activity. Bioaccessibility was measured by a mild chemical extraction method described in ref (1). Briefly, 1 g of soil was mixed with 10 ml of 400 mm hydroxypropyl-β-cyclodextrane (HPCD) solution. The HPCD was shaken, centrifuged and extracted with methanol. The HPCD-methanol solution was extracted with hexane to recover the chemicals followed by blown down to 1 ml and solvent exchanged to isooctane for analysis. Estimation of soil bacterial numbers in terms of colony forming units (CFUs) was performed by plate counts following the method described in ref (1). Quantitative analysis. 13 C 12 -PCB105 was added to the extracts as an internal standard. Quantitative analysis was performed by capillary gas chromatography - mass spectrometry (Agilent 6890 GC 5973 MSD) in electron capture negative ion mode (ECNI) for OCs and electron impact mode (EI) for PCBs. Analysis was done on a 60-m DB-5 column (0.25 mm i.d., 0.25 µm film, Agilent Technologies), with helium as the carrier gas. GC oven temperature program, ions monitored and settings on the MSD are detailed in ref (1). Enantiomers of 13 C 6 -α-hch were separated using the β-dexcst (BDXcst, proprietary composition, 30 m 0.25 mm i.d., 0.25 µm film thickness, Restek, Bellefonte, P.A, U.S.) as the primary column and BGB-172 column (BGB, 20% tert-butyldimethylsilylated β-cyclodextrin in OV-1701, 30 m x 0.25 mm i.d., 0.25 µm film thickness, BGB Analytik AG, Switzerland) as the secondary column for confirmation purpose. Instrument operating conditions are reported in Kurt-Karakus et al. (2). Results of enantiomer separations were expressed as enantiomer fraction (EF), defined as the peak areas of the (+)/[(+) + ( )] enantiomers. EF = indicates the S3

4 chemical is racemic, whereas EF indicates nonracemic. Data presented are an average of the primary and confirmation results. Quality Control. Limit of detection (LOD) was defined as mean blank + 3 times the standard deviation. If a chemical was not found in the blanks, LOD was defined as instrumental detection limit (IDL), which was estimated by injecting standards of the target analytes until a ~3:1 signal: noise ratio was obtained. There were no target analytes found in the soil blanks and HPCD blanks. Limit of detection for the OCs in soil were 0.16 to 1.6 ng g -1 ; and for PCBs ranged from 0.4 to 2.0 ng g -1 with 1 ml of sample extract and 1 g of soil. No OCs were found in the air blanks (n = 19) but trace levels were found of PCBs 8, 18, 32, 28, 52, 44, 66, 95, 101, 118 and 149. Their blank values ranged from 0.01 to 0.63 ng m -3 and are listed in Table SI-1. The percentage recovery of surrogates in air, soil and HPCD solutions were: 2 H 6 -γ-hch 86±10%, 85±10%, 84±10%; 13 C 10 -HEPX 104±15%, 93±20%, 123±20%; 13 C 12 -PCB-32 90±8%, 84±2%, 86±8%; 13 C 12 -PCB-77 99±9%, 106±11%, 105±10%; 13 C 12 -PCB ±9%, 102±21%, 94±10%; and 13 C 12 -PCB ±10%, 100±19%, 99±15%. Homogeneity of the soil was determined by extracting 5 sub-samples of the soil with DCM after 2 d of spiking. The relative standard deviations (%RSD) of chemical concentrations averaged 16%. The %RSD of K SA (25 sets of triplicate measurements) ranged from 7 to 23% (mean 15%) for native and spiked OCs, and from 6 to 16% (mean 10 %) for PCBs. In enantiomer analysis, ion ratios for each enantiomer peak were required to fall within the 95% confidence interval of standards for a satisfactory analysis; otherwise, the result was rejected. Standard EFs for 13 C 6 -α-hch were 0.501±0.002 (n = 19). Literature Cited. 1. Wong, F.; Bidleman, T. F. Using hydroxypropyl-beta-cyclodextrin as a mild extractant for organochlorine pesticides and polychlorinated biphenyls in muck soils. Environ. Pollut. 2010, 158, Kurt-Karakus, P. B.; Bidleman, T. F.; Jones, K. C. Chiral organochlorine pesticides signatures in global background soils. Environ. Sci. Technol. 2005, 39, ; corrections Ibid. 2006, S4

5 Figure SI-1. Air concentration (ng m -3 ) as a function of flow rate (L min -1 ) for muck soil. TC and Endo I H6 -γ-hch and p,p -DDT TC Endo I 2 H 6 -γ-hch p,p -DDT Flow Rate (L min -1 ) CC p,p -DDE and o,p -DDT CC p,p -DDE o,p -DDT Flow Rate (L min -1 ) S5

6 Figure SI-2. Plateau log K SA of spiked OCs and selected PCBs. Plateau Log K SA for Indoor (IN) ranged from Day 195 to 550, Outdoor (OUT) Day 390 to 730 and Sterile (ST) Day 210 to INDOOR OUTDOOR STERILE Plateau Log K SA C 6 -α-hch 13 C 10 -TC 13 C 10 -TN 13 C 12 -p,p'-ddt PCB 18 PCB 44 PCB 52 PCB 95 PCB 101 PCB 149 PCB 153 S6

7 Figure SI-3. HPCD extractability of selected OCs and PCBs for Indoor (IN), Outdoor (OUT) and Sterile (ST) soils. 45% TN IN 13 C 10 -TN 45% TN 13 C 10 -TN TN 13 C 10 -TN 45% OUT ST 35% 35% 35% 25% 25% 25% 15% % % % TC 13 C 10 -TC 55% TC 13 C 10 -TC TC 13 C 10 -TC 55% 45% 45% 45% HPCD extractability % 35% 35% 35% IN 25% 25% % 50% p,p'-ddt IN 13 C 12 -p,p'-ddt 60% 50% OUT OUT ST 25% p,p'-ddt 13 C 12 -p,p'-ddt p,p'-ddt 13 C 12 -p,p'-ddt 60% 50% ST 40% 30% 20% PCB 18 PCB 52 PCB 95 PCB % IN 60% 50% 40% 30% 20% % 30% 20% PCB 18 PCB 52 PCB 95 PCB % OUT 50% 40% 30% 20% % 30% 20% PCB 18 PCB 52 PCB 95 PCB % ST 60% 50% 40% 30% 20% Time (d) S7

8 Figure SI-4. Plateau log K SA of native OCs, spike OCs and PCBs vs. log K OA for Indoor, Outdoor and Sterile soils. Plateau log K SA of Indoor soils equals to mean log K SA from Day 195 to 550; Outdoor - from Day 390 to 730; Sterile - from Day 210 to 550. Solid line = log K SA predicted by the modified Karickhoff model. Spiked PCBs Native OCs Spiked 13 C-OCs Modified Karickhoff model 10 Indoor 10 Outdoor 10 Sterile log K SA log K OA S8

9 Figure SI-5. Ln C SOIL of 13 C 6 -α-hch, ENDO I, PCB 8 and 28 over the aging time for Indoor, Outdoor and Sterile soils. Day 60 to 230, 390 to 620 are the winter periods for the Outdoor soils C 6 -α-hch PCB Indoor -1 Indoor Ln C SOIL Outdoor Sterile Endo I Outdoor -2 Sterile PCB Indoor Outdoor Sterile Indoor Outdoor Sterile Time (d) S9

10 Table SI-1. Mean blanks and limits of detection (LOD) of PCBs in air. Mean Blank (ng/m 3 ) STDEV LOD 1 (ng/m 3 ) N 2 PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB LOD = Mean blank + 3*STDEV 2 N = 19 S10

11 Table SI-2. Soil bacteria colony forming units (CFU) for the Indoor, Outdoor and Sterile soils. Day Indoor Day Outdoor Day Sterile 2 2.7E E E E E E E E E E E E E E E E E E+05 S11

12 Table SI-3. Log K SA for the Indoor soils. Plateau is mean log K SA from 195 to 550d. INDOOR Plateau Plat STD TC CC TN Endo I Endo II ESUL o,p' -DDE p,p' -DDE o,p' -DDD p,p' -DDD nd o,p' -DDT p,p' -DDT C 6 -α-hch C 10 -TC C 10 -TN C 12 -p,p' -DDT PCB nd nd nd nd nd nd nd nd PCB PCB nd nd nd nd nd nd nd PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB S12

13 Table SI-4. Log K SA for the Outdoor soils. Plateau is mean log K SA from 390 to 730 d. OUTDOOR Plateau Plat STD TC CC TN Endo I Endo II ESUL o,p' -DDE p,p' -DDE o,p' -DDD nd p,p' -DDD o,p' -DDT p,p' -DDT C 6 -α-hch C 10 -TC C 10 -TN C 12 -p,p' -DDT PCB nd PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB nd S13

14 Table SI-5. Log K SA for the Sterile soils. Plateau is mean log K SA from 210 to 550 d. STERILE Plateau Plat STD TC CC TN Endo I Endo II ESUL o,p' -DDE p,p' -DDE o,p' -DDD p,p' -DDD o,p' -DDT p,p' -DDT C 6 -α-hch C 10 -TC C 10 -TN C 12 -p,p' -DDT PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB nd S14

15 Table SI-6. Relative K SA of OCs (Spiked/Native). Indoor TC TN p,p'-ddt Outdoor TC TN p,p'-ddt Sterile TC TN p,p'-ddt Ksa Spike/Native Indoor TC TN p,p'-ddt Ksa Spike/Native Sterile TC TN p,p'-ddt Time (d) Outdoor Time (d) Ksa Spike/Native TC TN p,p'-ddt Time (d) S15

16 Table SI-7. Indoor plateau log K SA for native OCs compared to literature values obtained from Meijer et al., (2003). Soil from the same farm was used in the Meijer study. log K SA This Study Meijer et al., 2003 TN o,p'-dde p,p'-dde o,p'-ddd p,p'-ddd o,p'-ddt S16

17 Table SI-8. HPCD extractability% for the Indoor soils (1). INDOOR TC CC TN Endo I Endo II ESUL o,p' -DDE p,p' -DDE o,p' -DDD p,p' -DDD o,p' -DDT p,p' -DDT C 6 -α-hch C 10 -TC C 10 -TN C 12 -p,p' -DDT PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB Literature Cited. 1. Wong, F.; Bidleman, T. F. Using hydroxypropyl-beta-cyclodextrin as a mild extractant for organochlorine pesticides and polychlorinated biphenyls in muck soils. Environ. Pollut. 2010, 158, S17

18 Table SI-9. HPCD extractability% for the Outdoor soils. OUTDOOR TC CC TN Endo I Endo II ESUL o,p' -DDE p,p' -DDE o,p' -DDD p,p' -DDD o,p' -DDT p,p' -DDT C 6 -α-hch C 10 -TC C 10 -TN C 12 -p,p' -DDT PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB S18

19 Table SI-10. HPCD extractability% for the Sterile soils. STERILE TC CC TN Endo I Endo II ESUL o,p' -DDE p,p' -DDE o,p' -DDD p,p' -DDD o,p' -DDT p,p' -DDT C 6 -α-hch C 10 -TC C 10 -TN C 12 -p,p' -DDT PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB PCB S19

20 Table SI-11. Half-lives of 13 C 6 -α-hch, endosulfans and PCB 8, 18, 28, 32 for Indoor and Outdoor soils. ns = No significant degradation or degradation does not follow first order kinetics. Indoor Half-lives (d) Outdoor Half-lives (d) 13 C 6 -α-hch Overall, 0 to 550 d 250 Overall, 0 to 730 d 230 (+) 0 to 550 d 155 (+) 0 to 730 d 205 ( ) 0 to 550 d 360 ( ) 0 to 730 d 255 Endo I 0 to 45 d to 730 d to 550 d 260 Endo II 0 to 550 d to 730 d ns ESUL 0 to 550 d to 730 d ns PCB 8 0 to 10 d 11 0 to 730 d to 550 d 230 PCB 18 0 to 550 d ns 0 to 730 d 2190 PCB 28 0 to 45 d 39 0 to 730 d to 550 d 270 PCB 32 0 to 550 d to 730 d 1260 S20