Environ. Sci. Technol. 2010, 44, 6608–6613
An Asia-Specific Source of Dechlorane Plus: Concentration, Isomer Profiles, and Other Related Compounds D E - G A O W A N G , * ,† M E N G Y A N G , † HONG QI,‡ ED SVERKO,§ WAN-LI MA,‡ Y I - F A N L I , * ,†,‡,§ M E H R A N A L A E E , § ERIC J. REINER,| AND LI SHEN| International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), Dalian Maritime University, Dalian, P. R. China, IJRC-PTS, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, P. R. China, Science and Technology Branch, Environment Canada, Toronto/ Burlington, Ontario, Canada, and Ontario Ministry of the Environment, Toronto, Ontario, Canada
Received April 16, 2010. Revised manuscript received June 22, 2010. Accepted July 9, 2010.
The distribution of dechloranes, a group of chlorinated flame retardants, were investigated in air, soil, and sediment around a newly discovered Dechlorane Plus (DP) production facility in China (Anpon). To date, the only known DP manufacturing plant is located in Niagara Falls, NY (OxyChem). Dechloranes including DP, Dechlorane (Mirex), and the recently discovered Dechlorane 602 (Dec 602) were detected in air, soil, and sediment, while Dechlorane 603 and Dechlorane 604 were below detection limit in all matrices. DP air concentrations near the facility ranged from 7737 to 26 734 pg m-3, the greatest reported thus far. Soil concentrations in the same area for DP, Dechlorane, and Dec 602 were 1490 ( 3580 ng g-1, 81.6 ( 96.5 ng g-1, and 7.24 ( 13.2 ng g-1 dry weight, respectively. Interestingly, lower concentrations of DP (4.93 ( 4.34 ng g-1), Dechlorane (30.2 ( 19.9 ng g-1), and Dec 602 (2.14 ( 2.23 ng g-1) were found in sediment from a nearby canal. Spatial trends of Dechlorane and Dec 602 in soil were similar to DP, implying that the DP manufacturing plant may also be a source of these other flame retardants. DP soil concentrations surrounding the facility decreased by an order of magnitude within 7.5 km. The syn-DP fractional abundance (fsyn) value (0.40) for the commercial DP product manufactured at Anpon was slightly higher than that (0.20-0.36) produced by OxyChem. The fsyn value in most air samples was largely similar to the Chinese commercial DP mixture, while most soil and sediment abundances were lower, suggesting a stereoselective depletion of syn-DP. * Address correspondence to either author. D.-G.W. phone: 86411-8472-8489; fax: 86-411-8472-8489; e-mail:
[email protected]. Y.-F.L. phone: 1-416-739-4892; fax: 1-416-739-4288; e-mail:
[email protected]. † International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), Dalian Maritime University. ‡ IJRC-PTS, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology. § Science and Technology Branch, Environment Canada. | Ontario Ministry of the Environment. 6608
9
ENVIRONMENTAL SCIENCE & TECHNOLOGY / VOL. 44, NO. 17, 2010
Introduction The occurrence of flame retardants (FRs) in the environment originating from production facilities has received considerable attention in recent years (1–3). Fugitive release of FRs during the manufacturing process has resulted in their deposition into the environment and exposure to local residents (2, 4). Much of the attention paid to the fate and effects of FRs has focused on the brominated class, such as polybrominated diphenyl ethers (PBDEs). Indeed, the three main PBDE commercial products were recently restricted and/or banned by the Stockholm Convention due to their persistence, toxicity, and bioaccumulation potential (5–7). While regulators focus on these brominated FRs, other nonbrominated FRs continue to currently go unabated. A series of chlorinated FRs known as dechloranes, most notably Dechlorane Plus (DP), are known to have been produced or patented. The earliest of the dechloranes simply named Dechlorane, or Mirex, was produced in the 1960s and banned a decade later due to its toxicity to humans and aquatic organisms (8). Dechlorane was partially replaced by DP (9). Other Dechloranes, Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603), and Dechlorane 604 (Dec 604), also patented by Hooker Chemical (now known as OxyChem) in the late 1960s and 1970s, were also used in a number of applications (10). These derivatives containing the basic biocyclo[2,2,1]heptene structures are hexachlorocyclopentadiene DielsAlder diadducts, which were used in commercial polymer products such as electrical wires and cables, plastic roofing materials, and connectors used in computers and televisions. Although these chemicals have been manufactured in the last four decades, very few reports exist on their environmental occurrence. In particular DP, with an annual production rate estimated to be as high as 5000 tons (11), has only been detected in air, sediment, and fish from the Laurentian Great Lakes in 2006 (12). Since then, DP was measured in various environmental matrices across the Northern Hemisphere, including air (11, 12), water (13–15), indoor dust (16), sediment (17–20), and biota (17, 21–25) (Figure 1). However, Dec 602, 603, and 604 were reported first in sediment and fish from the Laurentian Great Lakes in 2009 (10, 17). Several sources have been identified as contributing to the distribution of DP in the environment. First, urban/ industrial regions were ascribed as the main emission source of DP for these regions. Generally, two potential sources could be included: (i) industrial use of DP technical mixture for infusion into consumable products; and (ii) use and disposal of consumable products containing DP. Kang et al. measured DP in fish collected from Korea reporting that DP urban concentrations were approximately 25 times greater than those measured in rural areas (21), for which industrial emission played a vital role. Ren et al. measured DP concentrations in urban and rural air (China), with a mean value approximately 5 times higher in urban centers than those measured in rural areas. As well, a correlation was found between DP concentration and urban population, which implied sources were related to the urban activities of the use and disposal of consumable products containing DP (11). Another source is the practice of open burning of electronic waste (e-waste) cables and other electronic components located in various and unspecified locations throughout China (11). Luo et al. reported elevated DP concentrations in water (0.80 ng L-1), sediment (7590 ng g-1 dry weight), and biota (736 ng g-1 lipid) collected from e-waste 10.1021/es101224y
2010 American Chemical Society
Published on Web 08/03/2010
FIGURE 1. Locations of DP found to date. Air (11, 12), water (13–15), indoor dust (16), sediment (17–20), and biota (17, 21–25): Ren et al., 2008 (11); Hoh et al., 2006 (12); Qi et al., 2010 (13); Ma et al., 2010 (14); Luo et al., 2008 (15); Zhu et al., 2007 (16); Shen et al., 2009 (17); Qiu et al., 2007 (18); Sverko et al., 2008 (19); de la Torre et al., 2009 (20); Kang et al., 2009 (21); Gauthier et al., 2009 (22); Tomy et al., 2007 (23); Ren et al., 2010 (24); Qiu and Hites, 2008 (25). sites (15, 26). Ren et al. also found relatively greater DP serum concentrations in residents living at an e-waste dismantling site compared to those from outside of the area (24). Manufacturing can also be a source of DP to the environment. Hoh et al. reported the highest concentration of DP in air observed at a sampling location nearest the manufacturing facility (OxyChem) in Niagara Falls, NY (12). Furthermore, Qiu and Hites, when analyzing North American tree bark, noted concentrations in samples collected nearest OxyChem contained the greatest level of DP (25). Sverko et al. found that the amount of DP in sediment from Lake Ontario was 60-fold greater than that of Lake Erie (19). This is important because the manufacturer is located downstream of Lake Erie on the Niagara River which flows into Lake Ontario; the main source of DP to Lake Ontario. Gauthier et al. reported on a decreasing trend of DP concentrations in gull eggs with increasing distance from the same manufacturer (22). These reports suggest that the manufacturing facility plays an important role to the contribution of DP in the Great Lakes region. In their tree bark study, Qiu and Hites also measured relatively high concentrations in China and Korea suspecting there may be an Asian source of DP to the environment (25). In fact, we discovered a DP manufacturing plant, Jiangsu Anpon Electrochemical Company, in Huai’an, China operating since 2003 (http://www.anpon.com/English/Main.asp). Annual DP production amounts are estimated to be 300-1000 tons, totaling 2100-7000 tons to date. This new information shows that the DP burden to the Chinese environment is also supplemented by local DP manufacturing. Although it appears that DP concentrations in the North American Great Lakes are beginning to decrease (10, 12, 18, 19, 22, 27), it seems reasonable to believe that DP levels in China will continue to increase with greater volumes of e-waste recycling and DP manufacturing stemming from the growing Chinese economy and population. To the best of our knowledge, no information has been reported on the environmental levels of DP (and Dechloranes) in the vicinity of the Chinese manufacturing facility. In this paper, we describe DP concentrations from several air and sediment samples taken near the facility as well as spatial concentrations in soil, in the vicinity of and further afield from the Anpon plant.
Materials and Methods Chemical and Reagents. All solvents used were of pesticide grade purity (J.T. Baker, USA). Silica gel (100-200 mesh) was purchased from Merck (Germany). Analytical grade syn- and anti-DP (CAS 13560-89-9) were purchased from Wellington Laboratories (Guelph, ON). Commercial grade DP was obtained from Jiangsu Anpon Electrochemical Company (Huai’an, China). Dechlorane (Mirex, CAS 2385-85-5) was purchased from Cambridge Isotope Laboratories Inc. (Andover, MA). Dec 602 (95%, CAS 31107-44-5), Dec 603 (98%, CAS 13560-92-4), and Dec 604 (98%, CAS 34571-16-9) were purchased from Toronto Research Chemical Inc. (Toronto, ON). Molecular structures of these chemicals are shown in Figure S1, Supporting Information. Dechlorane, Dec 602, 603, and 604, syn-DP, and anti-DP were diluted in highpurity isooctane to five levels used as calibration standard solutions. Polychlorinated biphenyls 155 (CB 155) and octachloronaphthalene (OCN) purchased from Accustandard Inc. (New Haven, CT) were used as the surrogate and internal standards for all compounds. Sampling. A total of 3 air, 18 soil, and 2 sediment samples were collected concurrently from Huai’an in the Chinese province of Jiangsu in October 2009. The city of Huai’an is situated in eastern China (E 120°58′-123°31′, N 38°43′-40°10′) and locations of the sampling stations are shown in Figure 2. Three air samples were collected on three consecutive days October 10-13, 2009 with a high-volume air sampler (Laoshan Electronic Inc., Qingdao) using a rate of ∼0.8 m3 min-1 for 24 h on an outdoor building near the facility. Sampling volume was approximately 1150 m3. Air was drawn through a glass fiber filter (GFF, 20 cm ×25 cm) to collect particles and then through a cartridge containing two polyurethane foam (PUF) plugs (length 5.0 cm, diameter 9.5 cm) to collect compounds present in vapor phase. After sampling, the GFF was wrapped with prebaked aluminum foil, and PUF plugs were placed in acetone-rinsed glass flasks. A total of 15 surficial soil (0-5 cm) samples were collected from around the manufacturing facility (see Figure 2); details of the sampling method have been presented elsewhere (28). To investigate the leaching behavior of DP, samples were collected at depths 0-5, 30-40, 60-70, and 90-100 cm at W1 site close to the facility. The sediment sample was collected at 0-5 and 15-20 cm from a core in the BeijingHangzhou Grand Canal near the facility. Locations of all VOL. 44, NO. 17, 2010 / ENVIRONMENTAL SCIENCE & TECHNOLOGY
9
6609
FIGURE 2. Sampling sites in Huai’an (E 120°58′-123°31′, N 38°43′-40°10′), China. Three air samples were collected on three consecutive days October 10-13, 2009 on an outdoor building (sampling height ) 20 m) at the south facility. Fifteen surficial soil samples (E-East; W-West; S-South; N-North) were collected from around the manufacturing facility. Vertical depth soil samples were collected at different depths: 0-5, 30-40, 60-70, and 90-100 cm at W1 site. The sediment sample was collected at 0-5 and 15-20 cm from a core in the Beijing-Hangzhou Grand Canal near the facility. samples are summarized in Table 1. Soil and sediment samples were placed in prewashed glass jars and stored at -20 °C until extraction at the International Joint Research Center for Persistent Toxic Substances (IJRC-PTS). Extraction and Analyses. Samples were extracted and analyzed according to the methods established by the National Laboratory for Environmental Testing (NLET), Environment Canada (29, 30). Once spiked with CB 155 (50 ng/sample), all air, soil, and sediment samples were Soxhlet extracted. GFF and PUF samples were extracted with 120 mL of DCM and 550 mL of hexane/acetone (1:1, v/v) for 24 h, respectively. Extracts were purified using fully activated neutral silica (7 g) capped with 2 g of anhydrous sodium sulfate. The column was prewashed with 60 mL of DCM/ hexane (1:1, v/v). Once the 2-mL extracts were loaded onto the column, target compounds were collected using a 70mL mixture of DCM/hexane (1:1, v/v). Soil and sediment (wet weight 10 g) samples were extracted for 24 h with a 350-mL (1:1, v/v) mixture of hexane/acetone, which was then dried with anhydrous sodium sulfate and concentrated to 1 mL. The extracts were cleaned up using a column filled with 5 g of anhydrous sodium sulfate and 10 g of activated neutral silica gel. Following a prewash with 30 mL of hexane and 30 mL of DCM, the sample was added and eluted using 60 mL of a mix of DCM/hexane (1:1, v/v). The eluant was rotaryevaporated to approximately 4 mL, solvent-exchanged into isooctane, and reduced to gray. (A) Total DP, (B) Dechlorane, (C) Dec 602. play a significant role in soil. DP is degraded under aerobic conditions but not under anaerobic conditions (32). So biodegradation would not happen at deep soil layer and fsyn would not change with soil depth. Dec 602 concentrations showed maximal values (5.62 ng g-1 dw) at the surface, like DP, decreasing down to 0.267 ng g-1 at 90-100 cm. On the other hand, Dechlorane concentrations were detected at a shallower depth of 40 cm. This is surprising as the diffuse nature of Dechlorane in surface soil would indicate an old signature; counterintuitive to the observed relative depth profile of the more recently introduced Dec 602. One explanation may be the preferential adsorption tendencies of Dechlorane over Dec 602. More studies are needed to fully understand this process. Our results suggest that the manufacturing facility in Jiangsu, China is a significant source of DP to the surrounding area. Concentrations of DP in air near the facility were severalfold greater than those reported in Chinese urban centers and a North American region where the known DP manufacturing plant OxyChem is located. Although we were unable to uncover any production records for Dechlorane and Dec 602 at the Anpon facility, soil measurements indicate some activity to their production and/or use exists.
Acknowledgments This study was supported by the China National Natural Science Foundation Program (Grant 20807008) and the Fundamental Research Funds for the Central Universities (DLMU-2009QN059).
(14)
(15)
Supporting Information Available Structure (Figure S1) of Dechloranes; three day back trajectories based on the National Oceanic and Atmospheric Administration (NOAA) HYSPLIT model in air sampling period (Figure S2); concentration relationship between DP with Dec 602 and Dechlorane in soil (Figure S3); DP concentration in soil as a function of distance from the manufacturing plant (Figure S4); vertical distribution of Dechloranes in soil at one site close to the facility (Figure S5). This material is available free of charge via the Internet at http://pubs.acs.org.
(16) (17)
(18) (19)
Literature Cited (1) Ruan, T.; Wang, Y. W.; Wang, C.; Wang, P.; Fu, J. J.; Yin, Y. G.; Qu, G. B.; Wang, T.; Jiang, G. B. Identification and evaluation of a novel heterocyclic brominated flame retardant tris(2,3dibromopropyl) isocyanurate in environmental matrices near a manufacturing plant in southern China. Environ. Sci. Technol. 2009, 43 (9), 3080–3086. (2) Jin, J.; Wang, Y.; Yang, C.; Hu, J.; Liu, W.; Cui, J.; Tang, X. Polybrominated diphenyl ethers in the serum and breast milk of the resident population from production area, China. Environ. Int. 2009, 35 (7), 1048–1052. (3) Sverko, E.; Reiner, E. J.; Tomy, G. T.; McCrindle, R.; Shen, L.; Arsenault, G.; Zaruk, D.; MacPherson, K. A.; Marvin, C. H.; Helm, P. A.; McCarry, B. E. Compounds structurally related to dechlorane plus in sediment and biota from Lake Ontario (Canada). Environ. Sci. Technol. 2010, 44 (2), 574–579. (4) Jin, J.; Liu, W.; Wang, Y.; Tang, X. Y. Levels and distribution of polybrominated diphenyl ethers in plant, shellfish and sediment samples from Laizhou Bay in China. Chemosphere 2008, 71 (6), 1043–1050. (5) de Wit, C. A.; Alaee, M.; Muir, D. C. G. Levels and trends of brominated flame retardants in the Arctic. Chemosphere 2006, 64 (2), 209–233. (6) Law, R. J.; Alaee, M.; Allchin, C. R.; Boon, J. P.; Lebeuf, M.; Lepom, P.; Stern, G. A. Levels and trends of polybrominated diphenylethers and other brominated flame retardants in wildlife. Environ. Int. 2003, 29 (6), 757–770. (7) Alaee, M.; Arias, P.; Sjo¨din, A.; Bergman, Å. An overview of commercially used brominated flame retardants, their applications, their use patterns in different countries/regions and possible modes of release. Environ. Int. 2003, 29 (6), 683–689. (8) Kaiser, K. The rise and fall of mirex. Environ. Sci. Technol. 1978, 12 (5), 520–528. (9) International Programme on Chemical Safety. Environmental Health Criteria 44, Mirex. http://www.inchem.org/documents/ ehc/ehc44.htm (Accessed June 2009). (10) Shen, L.; Reiner, E. J.; MacPherson, K. A.; Kolic, T. M.; Sverko, E.; Helm, P. A.; Bhavsar, S. P.; Brindle, I. D.; Marvin, C. H. Identification and screening analysis of halogenated norbornene flame retardants in the Laurentian Great Lakes: Dechloranes 602, 603, and 604. Environ. Sci. Technol. 2010, 44 (2), 760–766. (11) Ren, N.; Sverko, E.; Li, Y.-F.; Zhang, Z.; Harner, T.; Wang, D.; Wan, X.; McCarry, B. E. Levels and isomer profiles of dechlorane plus in Chinese air. Environ. Sci. Technol. 2008, 42 (17), 6476– 6480. (12) Hoh, E.; Zhu, L.; Hites, R. A. Dechlorane plus, a chlorinated flame retardant, in the Great Lakes. Environ. Sci. Technol. 2006, 40 (4), 1184–1189. (13) Qi, H.; Liu, L.; Jia, H.; Li, Y.-F.; Ren, N.-Q.; You, H.; Shi, X.; Fan, L.; Ding, Y. Dechlorane plus in surficial water and sediment in
(20) (21) (22)
(23)
(24)
(25) (26)
(27)
(28)
(29)
(30)
(31) (32)
a Northeastern Chinese River. Environ. Sci. Technol. 2010, 44 (7), 2305–2308. Ma, W.-L.; Liu, L.-Y.; Qi, H.; Sun, D.-Z.; Shen, J.-M.; Wang, D.G.; Li, Y.-F. Dechlorane Plus in multimedia in northeastern Chinese urban region. Environ. Int. 2010, in press, DOI: 10.1016/ j.envint.2010.07.002. Luo, X.-J.; Wu, J.-P.; Zhang, Y.; Wang, J.; Chen, S.-J.; Mai, B.-X. Bioaccumulation of dechlorane plus in aquatic food web from an electronic waste recycling site, south China. Organohalogen Compd. 2009, 71, 3060–3065. Zhu, J.; Feng, Y.-l.; Shoeib, M. Detection of dechlorane plus in residential indoor dust in the city of Ottawa, Canada. Environ. Sci. Technol. 2007, 41 (22), 7694–7698. Shen, L.; Reiner, E.; Mac, P.; Kolic, T.; Helm, P.; Sverko, E.; Bhavsar, S.; Brindle, I.; Marvin, C. New halogenated norbornene flame retardants in the Laurentian Great Lakes: Dechloranes 602, 603 and 604. Organohalogen Compd. 2009, 71, 2309–2314. Qiu, X.; Marvin, C. H.; Hites, R. A. Dechlorane plus and other flame retardants in a sediment core from Lake Ontario. Environ. Sci. Technol. 2007, 41 (17), 6014–6019. Sverko, E.; Tomy, G. T.; Marvin, C. H.; Zaruk, D.; Reiner, E.; Helm, P. A.; Hill, B.; McCarry, B. E. Dechlorane plus levels in sediment of the lower Great Lakes. Environ. Sci. Technol. 2008, 42 (2), 361–366. ´ . Detection de la Torre, A.; Sverko, E.; Alaee, M.; Martı´nez, M. A of an “emerging” flame retardant, dechlorane plus, in Spanish sewage sludge. Organohalogen Compd. 2009, 71, 2113–2117. Kang, J.; Kim, J.; Chang, Y.-S. Dechlorane plus in fish from urbanindustrial rivers. Organohalogen Compd. 2009, 71, 1356–1359. Gauthier, L. T.; Letcher, R. J. Isomers of Dechlorane Plus flame retardant in the eggs of herring gulls (Larus argentatus) from the Laurentian Great Lakes of North America: Temporal changes and spatial distribution. Chemosphere 2009, 75 (1), 115–120. Tomy, G. T.; Pleskach, K.; Ismail, N.; Whittle, D. M.; Helm, P. A.; Sverko, E.; Zaruk, D.; Marvin, C. H. Isomers of dechlorane plus in Lake Winnipeg and Lake Ontario food webs. Environ. Sci. Technol. 2007, 41 (7), 2249–2254. Ren, G.; Yu, Z.; Ma, S.; Li, H.; Peng, P.; Sheng, G.; Fu, J. Determination of Dechlorane Plus in serum from electronics dismantling workers in south China. Environ. Sci. Technol. 2010, 43 (24), 9453–9457. Qiu, X.; Hites, R. A. Dechlorane plus and other flame retardants in tree bark from the northeastern United States. Environ. Sci. Technol. 2008, 42 (1), 31–36. Wu, J.-P.; Zhang, Y.; Luo, X.-J.; Wang, J.; Chen, S.-J.; Guan, Y.-T.; Mai, B.-X. Isomer-specific bioaccumulation and trophic transfer of dechlorane plus in the freshwater food web from a highly contaminated site, south China. Environ. Sci. Technol. 2010, 44 (2), 606–611. Ismail, N.; Gewurtz, S. B.; Pleskach, K.; Whittle, D. M.; Helm, P. A.; Marvin, C. H.; Tomy, G. T. Brominated and chlorinated flame retardants in Lake Ontario, Canada, Lake Trout (Salvelinus Namaycush) between 1979 and 2004 and possible influences of food-web changes. Environ. Toxicol. Chem. 2009, 28 (5), 910– 920. Wang, D.-G.; Yang, M.; Jia, H.-l.; Zhou, L.; Li, Y.-F. Polycyclic aromatic hydrocarbons in urban street dust and surface soil: Comparisons of concentration, distribution and source. Arch. Environ. Contam. Toxicol. 2009, 56 (2), 173–180. Su, Y.; Hung, H.; Sverko, E.; Fellin, P.; Li, H. Multi-year measurements of polybrominated diphenyl ethers (PBDEs) in the arctic atmosphere. Atmos. Environ. 2007, 41 (38), 8725– 8735. Marvin, C. H.; Sverko, E.; Charlton, M. N.; Theissen, P. A. L.; Painter, S. Contaminants associated with suspended sediments in Lakes Erie and Ontario,1997-2000. J. Great Lakes Res. 2004, 30 (2), 277–286. Zitko, V. The uptake and excretion of mirex and dechloranes by juvenile Atlantic salmon. Chemosphere 1980, 9 (2), 73–78. OxyChem Dechlorane Plus Handbook. http://www.oxy.com/ Our_Businesses/chemicals/Documents/dechlorane_plus/ dechlorane_plus.pdf (Accessed Jun 2010).
ES101224Y
VOL. 44, NO. 17, 2010 / ENVIRONMENTAL SCIENCE & TECHNOLOGY
9
6613
