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Volumn 43, Issue 17, 2009, Pages 6507-6514

Polyfluorinated compounds in the atmosphere of the Atlantic and Southern Oceans: Evidence for a global distribution

Author keywords

[No Author keywords available]

Indexed keywords

AIR SAMPLES; ANALYTES; ANTARCTIC REGIONS; ANTARCTICA; ATLANTIC OCEAN; BALTIC SEA; CENTRAL EUROPE; DATA SETS; FLUOROTELOMER ALCOHOLS; GAS-PHASE CONCENTRATION; GASPHASE; GERMANY; GLASS FIBER FILTERS; GLOBAL DISTRIBUTION; HPLC-MS/MS; LONG RANGE TRANSPORT; MARINE REGION; NON-VOLATILE; NORTHERN HEMISPHERES; REMOTE REGIONS; RESEARCH VESSELS; RESIDENCE TIME; SOURCE REGION; SOUTHERN OCEAN;

EID: 69549110666     PISSN: 0013936X     EISSN: 15205851     Source Type: Journal    
DOI: 10.1021/es9010465     Document Type: Article
Times cited : (185)

References (55)
  • 1
    • 36049021902 scopus 로고    scopus 로고
    • Perfluoroalkyl acids: A review of monitoring and toxicological findings
    • DOI 10.1093/toxsci/kfm128
    • Lau, C.; Anitole, K.; Hodes, C.; Lai, D.; Pfahles-Hutchens, A.; Seed, J. Perfluoroalkyl acids: A review of monitoring and toxicological findings. Toxicol. Sci. 2007, 99, 366-394. (Pubitemid 351753056)
    • (2007) Toxicological Sciences , vol.99 , Issue.2 , pp. 366-394
    • Lau, C.1    Anitole, K.2    Hodes, C.3    Lai, D.4    Pfahles-Hutchens, A.5    Seed, J.6
  • 2
    • 39649084641 scopus 로고    scopus 로고
    • Are PFCAs bioaccumulative? A critical review and comparison with regulatory lipophilic compounds
    • Conder, J. M.; Hoke, R. A.; De Wolf, W.; Russell, M. H.; Buck, R. C. Are PFCAs bioaccumulative? A critical review and comparison with regulatory lipophilic compounds. Environ. Sci. Technol. 2008, 42, 995-1003.
    • (2008) Environ. Sci. Technol. , vol.42 , pp. 995-1003
    • Conder, J.M.1    Hoke, R.A.2    De Wolf, W.3    Russell, M.H.4    Buck, R.C.5
  • 3
    • 34247120708 scopus 로고    scopus 로고
    • Serum concentrations of 11 polyfluoroalkyl compounds in the US population: Data from the National Health and Nutrition Examination Survey (NHANES) 1999-2000
    • Calafat, A. M.; Kuklenyik, Z.; Reidy, J. A.; Caudill, S. P.; Tully, J. S.; Needham, L. L. Serum concentrations of 11 polyfluoroalkyl compounds in the US population: Data from the National Health and Nutrition Examination Survey (NHANES) 1999-2000. Environ. Sci. Technol. 2007, 41, 2237-2242.
    • (2007) Environ. Sci. Technol. , vol.41 , pp. 2237-2242
    • Calafat, A.M.1    Kuklenyik, Z.2    Reidy, J.A.3    Caudill, S.P.4    Tully, J.S.5    Needham, L.L.6
  • 4
    • 33845727205 scopus 로고    scopus 로고
    • Perfluorooctanesulfonate and related fluorochemicals in albatrosses, elephant seals, penguins, and Polar Skuas from the Southern Ocean
    • Tao, L.; Kannan, K.; Kajiwara, N.; Costa, M. M.; Fillmann, G.; Takahashi, S.; Tanabe, S. Perfluorooctanesulfonate and related fluorochemicals in albatrosses, elephant seals, penguins, and Polar Skuas from the Southern Ocean. Environ. Sci. Technol. 2006, 40, 7642-7648.
    • (2006) Environ. Sci. Technol. , vol.40 , pp. 7642-7648
    • Tao, L.1    Kannan, K.2    Kajiwara, N.3    Costa, M.M.4    Fillmann, G.5    Takahashi, S.6    Tanabe, S.7
  • 5
    • 33144459828 scopus 로고    scopus 로고
    • Temporal trends of perfluoroalkyl contaminants in polar bears (Ursus maritimus) from two locations in the North American Arctic, 1972-2002
    • Smithwick, M.; Norstrom, R. J.; Mabury, S. A.; Solomon, K.; Evans, T. J.; Stirling, I.; Taylor, M. K.; Muir, D. C. G. Temporal trends of perfluoroalkyl contaminants in polar bears (Ursus maritimus) from two locations in the North American Arctic, 1972-2002. Environ. Sci. Technol. 2006, 40, 1139-1143.
    • (2006) Environ. Sci. Technol. , vol.40 , pp. 1139-1143
    • Smithwick, M.1    Norstrom, R.J.2    Mabury, S.A.3    Solomon, K.4    Evans, T.J.5    Stirling, I.6    Taylor, M.K.7    Muir, D.C.G.8
  • 6
    • 37649021611 scopus 로고    scopus 로고
    • Perfluorinated acids as novel chemical tracers of global circulation of ocean waters
    • Yamashita, N.; Taniyasu, S.; Petrick, G.; Wei, S.; Gamo, T.; Lam, P. K. S.; Kannan, K. Perfluorinated acids as novel chemical tracers of global circulation of ocean waters. Chemosphere 2008, 70, 1247-1255.
    • (2008) Chemosphere , vol.70 , pp. 1247-1255
    • Yamashita, N.1    Taniyasu, S.2    Petrick, G.3    Wei, S.4    Gamo, T.5    Lam, P.K.S.6    Kannan, K.7
  • 7
    • 35948942266 scopus 로고    scopus 로고
    • Riverine discharge of perfluorinated carboxylates from the European continent
    • DOI 10.1021/es071471p
    • McLachlan, M. S.; Holmstrom, K. E.; Reth, M.; Berger, U. Riverine discharge of perfluorinated carboxylates from the European continent. Environ. Sci. Technol. 2007, 41, 7260-7265. (Pubitemid 350071632)
    • (2007) Environmental Science and Technology , vol.41 , Issue.21 , pp. 7260-7265
    • Mclachlan, M.S.1    Holmstrom, K.E.2    Reth, M.3    Berger, U.4
  • 10
    • 62749133986 scopus 로고    scopus 로고
    • A First Global Production, Emission, and Environmental Inventory for Perfluorooctane Sulfonate
    • Paul, A. G.; Jones, K. C.; Sweetman, A. J. A First Global Production, Emission, And Environmental Inventory For Perfluorooctane Sulfonate. Environ. Sci. Technol. 2009, 43, 386-392.
    • (2009) Environ. Sci. Technol. , vol.43 , pp. 386-392
    • Paul, A.G.1    Jones, K.C.2    Sweetman, A.J.3
  • 11
    • 34447263264 scopus 로고    scopus 로고
    • A global mass balance analysis of the source of perfluorocarboxylic acids in the Arctic Ocean
    • DOI 10.1021/es070124c
    • Wania, F. A global mass balance analysis of the source of perfluorocarboxylic acids in the Arctic ocean. Environ. Sci. Technol. 2007, 41, 4529-4535. (Pubitemid 47047384)
    • (2007) Environmental Science and Technology , vol.41 , Issue.13 , pp. 4529-4535
    • Wania, F.1
  • 13
    • 0442311068 scopus 로고    scopus 로고
    • Atmospheric chemistry of perfluorinated carboxylic acids: Reaction with OH radicals and atmospheric lifetimes
    • Hurley, M. D.; Andersen, M. P. S.; Wallington, T. J.; Ellis, D. A.; Martin, J. W.; Mabury, S. A. Atmospheric chemistry of perfluorinated carboxylic acids: Reaction with OH radicals and atmospheric lifetimes. J. Phys. Chem. A 2004, 108, 615-620.
    • (2004) J. Phys. Chem. A , vol.108 , pp. 615-620
    • Hurley, M.D.1    Andersen, M.P.S.2    Wallington, T.J.3    Ellis, D.A.4    Martin, J.W.5    Mabury, S.A.6
  • 15
    • 33644869626 scopus 로고    scopus 로고
    • Significant residual fluorinated alcohols present in various fluorinated materials
    • Dinglasan-Panlilio, M. J. A.; Mabury, S. A. Significant residual fluorinated alcohols present in various fluorinated materials. Environ. Sci. Technol. 2006, 40, 1447-1453.
    • (2006) Environ. Sci. Technol. , vol.40 , pp. 1447-1453
    • Dinglasan-Panlilio, M.J.A.1    Mabury, S.A.2
  • 16
    • 33847213889 scopus 로고    scopus 로고
    • Quantitation of gas-phase perfluoroalkyl surfactants and fluorotelomer alcohols released from nonstick cookware and microwave popcorn bags
    • DOI 10.1021/es062377w
    • Sinclair, E.; Kim, S. K.; Akinleye, H. B.; Kannan, K. Quantitation of gas-phase perfluoroalkyl surfactants and fluorotelomer alcohols released from nonstick cookware and microwave popcorn bags. Environ. Sci. Technol. 2007, 41, 1180-1185. (Pubitemid 46302669)
    • (2007) Environmental Science and Technology , vol.41 , Issue.4 , pp. 1180-1185
    • Sinclair, E.1    Kim, S.K.2    Akinleye, H.B.3    Kannan, K.4
  • 17
    • 33645229102 scopus 로고    scopus 로고
    • Atmospheric chemistry of N-methyl perfluorobutane sulfonamidoethanol, C4F9SO2N(CH3)CH2CH2OH: Kinetics and mechanism of reaction with OH
    • D'Eon, J. C.; Hurley, M. D.; Wallington, T. J.; Mabury, S. A. Atmospheric chemistry of N-methyl perfluorobutane sulfonamidoethanol, C4F9SO2N(CH3) CH2CH2OH: Kinetics and mechanism of reaction with OH. Environ. Sci. Technol. 2006, 40, 1862-1868.
    • (2006) Environ. Sci. Technol. , vol.40 , pp. 1862-1868
    • D'Eon, J.C.1    Hurley, M.D.2    Wallington, T.J.3    Mabury, S.A.4
  • 20
    • 32344444989 scopus 로고    scopus 로고
    • Atmospheric chemistry of perfluoroalkanesulfonamides: Kinetic and product studies of the OH radical and Cl atom initiated oxidation of N-ethyl perfluorobutanesulfonamide
    • Martin, J. W.; Ellis, D. A.; Mabury, S. A.; Hurley, M. D.; Wallington, T. J. Atmospheric chemistry of perfluoroalkanesulfonamides: Kinetic and product studies of the OH radical and Cl atom initiated oxidation of N-ethyl perfluorobutanesulfonamide. Environ. Sci. Technol. 2006, 40, 864-872.
    • (2006) Environ. Sci. Technol. , vol.40 , pp. 864-872
    • Martin, J.W.1    Ellis, D.A.2    Mabury, S.A.3    Hurley, M.D.4    Wallington, T.J.5
  • 21
    • 51449084659 scopus 로고    scopus 로고
    • Current levels of airborne polyfluorinated telomers in Japan
    • Oono, S.; Harada, K. H.; Mahmoud, M. A. M.; Inoue, K.; Koizumi, A. Current levels of airborne polyfluorinated telomers in Japan. Chemosphere 2008, 73, 932-937.
    • (2008) Chemosphere , vol.73 , pp. 932-937
    • Oono, S.1    Harada, K.H.2    Mahmoud, M.A.M.3    Inoue, K.4    Koizumi, A.5
  • 22
    • 33845801634 scopus 로고    scopus 로고
    • Perfluorinated chemicals in the Arctic atmosphere
    • Shoeib, M.; Harner, T.; Vlahos, P. Perfluorinated chemicals in the Arctic atmosphere. Environ. Sci. Technol. 2006, 40, 7577-7583.
    • (2006) Environ. Sci. Technol. , vol.40 , pp. 7577-7583
    • Shoeib, M.1    Harner, T.2    Vlahos, P.3
  • 23
    • 34248149528 scopus 로고    scopus 로고
    • Latitudinal gradient of airborne polyfluorinated alkyl substances in the marine atmosphere between Germany and South Africa (53degrees N-33degrees S)
    • DOI 10.1021/es062389h
    • Jahnke, A.; Berger, U.; Ebinghaus, R.; Temme, C. Latitudinal gradient of airborne polyfluorinated alkyl substances in the marine atmosphere between Germany and South Africa (53 degrees N-33 degrees S). Environ. Sci. Technol. 2007, 41, 3055-3061. (Pubitemid 46713359)
    • (2007) Environmental Science and Technology , vol.41 , Issue.9 , pp. 3055-3061
    • Jahnke, A.1    Berger, U.2    Ebinghaus, R.3    Temme, C.4
  • 25
    • 66249113543 scopus 로고    scopus 로고
    • Annual time-series of air concentrations of polyfluorinated compounds (PFC)
    • Dreyer, A.; Matthias, V.; Temme, C.; Ebinghaus, R. Annual time-series of air concentrations of polyfluorinated compounds (PFC). Environ. Sci. Technol. 2009, 43, 4029-4036.
    • (2009) Environ. Sci. Technol. , vol.43 , pp. 4029-4036
    • Dreyer, A.1    Matthias, V.2    Temme, C.3    Ebinghaus, R.4
  • 30
    • 41649116717 scopus 로고    scopus 로고
    • Altitudinal transect of atmospheric and aqueous fluorinated organic compounds in western Canada
    • Loewen, M.; Wania, F.; Wang, F. Y.; Tomy, G. Altitudinal transect of atmospheric and aqueous fluorinated organic compounds in western Canada. Environ. Sci. Technol. 2008, 42, 2374-2379.
    • (2008) Environ. Sci. Technol. , vol.42 , pp. 2374-2379
    • Loewen, M.1    Wania, F.2    Wang, F.Y.3    Tomy, G.4
  • 31
    • 18344388873 scopus 로고    scopus 로고
    • Fluorotelomer carboxylic acids and PFOS in rainwater from an urban center in Canada
    • DOI 10.1021/es048635b
    • Loewen, M.; Halldorson, T.; Wang, F. Y.; Tomy, G. Fluorotelomer carboxylic acids and PFOS in rainwater from an urban center in Canada. Environ. Sci. Technol. 2005, 39, 2944-2951. (Pubitemid 40638230)
    • (2005) Environmental Science and Technology , vol.39 , Issue.9 , pp. 2944-2951
    • Loewen, M.1    Halldorson, T.2    Wang, F.3    Tomy, G.4
  • 32
    • 33845301231 scopus 로고    scopus 로고
    • Poly and perfluorinated carboxylates in north American precipitation
    • Scott, B. F.; Spencer, C.; Mabury, S. A.; Muir, D. C. G. Poly and perfluorinated carboxylates in north American precipitation. Environ. Sci. Technol. 2006, 40, 7167-7174.
    • (2006) Environ. Sci. Technol. , vol.40 , pp. 7167-7174
    • Scott, B.F.1    Spencer, C.2    Mabury, S.A.3    Muir, D.C.G.4
  • 33
    • 34250858388 scopus 로고    scopus 로고
    • Perfluoroalkyl contaminants in the canadian arctic: Evidence of atmospheric transport and local contamination
    • Stock, N. L.; Furdui, V. I.; Muir, D. C. G.; Mabury, S. A. Perfluoroalkyl contaminants in the canadian arctic: Evidence of atmospheric transport and local contamination. Environ. Sci. Technol. 2007, 41, 3529-3536.
    • (2007) Environ. Sci. Technol. , vol.41 , pp. 3529-3536
    • Stock, N.L.1    Furdui, V.I.2    Muir, D.C.G.3    Mabury, S.A.4
  • 34
    • 59349120525 scopus 로고    scopus 로고
    • Polyfluorinated Compounds in Ambient Air from ship- and land-based measurements in northern Germany
    • Dreyer, A.; Ebinghaus, R. Polyfluorinated Compounds in Ambient Air from ship- and land-based measurements in northern Germany. Atmos. Environ. 2009, 43, 1527-1535.
    • (2009) Atmos. Environ. , vol.43 , pp. 1527-1535
    • Dreyer, A.1    Ebinghaus, R.2
  • 35
    • 37549051689 scopus 로고    scopus 로고
    • Optimized method avoiding solvent-induced response enhancement in the analysis of volatile and semi-volatile polyfluorinated alkylated compounds using gas chromatography-mass spectrometry
    • DOI 10.1016/j.chroma.2007.11.050, PII S0021967307020006
    • Dreyer, A.; Temme, C.; Sturm, R.; Ebinghaus, R. Optimized method avoiding solvent-induced response enhancement in the analysis of volatile and semi-volatile polyfluorinated alkylated compounds using gas chromatography-mass spectrometry. J. Chromatogr., A 2008, 1178, 199-205. (Pubitemid 50015051)
    • (2008) Journal of Chromatography a , vol.1178 , Issue.1-2 , pp. 199-205
    • Dreyer, A.1    Temme, C.2    Sturm, R.3    Ebinghaus, R.4
  • 37
    • 0001018481 scopus 로고
    • Residence time and variability of tropospheric trace gases
    • Junge, C. E. Residence time and variability of tropospheric trace gases. Tellus 1974, 26, 477-488.
    • (1974) Tellus , vol.26 , pp. 477-488
    • Junge, C.E.1
  • 38
    • 0024731195 scopus 로고
    • Seasonal variation in the atmospheric concentration of polychlorinated biphenyl congeners
    • Manchester-Neesvig, J. B.; Andren, A. W. Seasonal variation in the atmospheric concentration of polychlorinated biphenyl congeners. Environ. Sci. Technol. 1989, 23, 1138-1148. (Pubitemid 19226564)
    • (1989) Environmental Science and Technology , vol.23 , Issue.9 , pp. 1138-1148
    • Manchester-Neesvig, J.B.1    Andren, A.W.2
  • 39
    • 51349117607 scopus 로고    scopus 로고
    • Irreversible sorption of trace concentrations of perfluorocarboxylic acids to fiber filters used for air sampling
    • Arp, H. P. H.; Goss, K. U. Irreversible sorption of trace concentrations of perfluorocarboxylic acids to fiber filters used for air sampling. Atmos. Environ. 2008, 42, 6869-6872.
    • (2008) Atmos. Environ. , vol.42 , pp. 6869-6872
    • Arp, H.P.H.1    Goss, K.U.2
  • 41
    • 38849132920 scopus 로고    scopus 로고
    • Sorbent-impregnated polyurethane foam disk for passive air sampling of volatile fluorinated chemicals
    • Shoeib, M.; Harner, T.; Lee, S. C.; Lane, D.; Zhu, J. P. Sorbent-impregnated polyurethane foam disk for passive air sampling of volatile fluorinated chemicals. Anal. Chem. 2008, 80, 675-682.
    • (2008) Anal. Chem. , vol.80 , pp. 675-682
    • Shoeib, M.1    Harner, T.2    Lee, S.C.3    Lane, D.4    Zhu, J.P.5
  • 42
    • 69549122721 scopus 로고    scopus 로고
    • Poly- and perfluorinated compounds in household consumer products
    • submitted
    • Fiedler, S.; Pfister, G.; Schramm, K.-W. Poly- and perfluorinated compounds in household consumer products. Chemosphere, submitted.
    • Chemosphere
    • Fiedler, S.1    Pfister, G.2    Schramm, K.-W.3
  • 44
    • 33846781594 scopus 로고    scopus 로고
    • Urban versus remote air concentrations of fluorotelomer alcohols and other polyfluorinated alkyl substances in Germany
    • DOI 10.1021/es0619861
    • Jahnke, A.; Ahrens, L.; Ebinghaus, R.; Temme, C. Urban versus remote air concentrations of fluorotelomer alcohols and other polyfluorinated alkyl substances in Germany. Environ. Sci. Technol. 2007, 41, 745-752. (Pubitemid 46208505)
    • (2007) Environmental Science and Technology , vol.41 , Issue.3 , pp. 745-752
    • Jahnke, A.1    Ahrens, L.2    Ebinghaus, R.3    Temme, C.4
  • 46
    • 0036468374 scopus 로고    scopus 로고
    • Collection of airborne fluorinated organics and analysis by gas chromatography/chemical ionization mass spectrometry
    • DOI 10.1021/ac015630d
    • Martin, J. W.; Muir, D. C. G.; Moody, C. A.; Ellis, D. A.; Kwan, W. C.; Solomon, K. R.; Mabury, S. A. Collection of airborne fluorinated organicsandanalysisbygas chromatography/chemical ionization mass spectrometry. Anal. Chem. 2002, 74, 584-590. (Pubitemid 34131508)
    • (2002) Analytical Chemistry , vol.74 , Issue.3 , pp. 584-590
    • Martin, J.W.1    Muir, D.C.G.2    Moody, C.A.3    Ellis, D.A.4    Wai, C.K.5    Solomon, K.R.6    Mabury, S.A.7
  • 47
    • 54749137394 scopus 로고    scopus 로고
    • Passive Air Sampling of Polychlorinated Biphenyls and Organochlorine Pesticides at the Korean Arctic and Antarctic Research Stations: Implications for Long-Range Transport and Local Pollution
    • Choi, S.-D.; Baek, S.-Y.; Chang, Y.-S.; Wania, F.; Ikonomou, M. G.; Yoon, Y.-J.; Park, B.-K.; Hong, S. Passive Air Sampling of Polychlorinated Biphenyls and Organochlorine Pesticides at the Korean Arctic and Antarctic Research Stations: Implications for Long-Range Transport and Local Pollution. Environ. Sci. Technol. 2008, 42, 7125-7131.
    • (2008) Environ. Sci. Technol. , vol.42 , pp. 7125-7131
    • Choi, S.-D.1    Baek, S.-Y.2    Chang, Y.-S.3    Wania, F.4    Ikonomou, M.G.5    Yoon, Y.-J.6    Park, B.-K.7    Hong, S.8
  • 48
    • 21244447619 scopus 로고    scopus 로고
    • PCBs and chlorinated pesticides (DDTs, HCHs, and HCB) in the atmosphere of the southwest Atlantic and Antarctic oceans
    • Montone, R. C.; Taniguchi, S.; Boian, C.; Weber, R. R. PCBs and chlorinated pesticides (DDTs, HCHs, and HCB) in the atmosphere of the southwest Atlantic and Antarctic oceans. Mar. Pollut. Bull. 2005, 50, 778-782.
    • (2005) Mar. Pollut. Bull. , vol.50 , pp. 778-782
    • Montone, R.C.1    Taniguchi, S.2    Boian, C.3    Weber, R.R.4
  • 51
    • 2342533253 scopus 로고    scopus 로고
    • Evidence for dynamic air-water coupling and cycling of persistent organic pollutants over the open Atlantic Ocean
    • Jaward, F. M.; Barber, J. L.; Booij, K.; Dachs, J.; Lohmann, R.; Jones, K. C. Evidence for dynamic air-water coupling and cycling of persistent organic pollutants over the open Atlantic Ocean. Environ. Sci. Technol. 2004, 38, 2617-2625.
    • (2004) Environ. Sci. Technol. , vol.38 , pp. 2617-2625
    • Jaward, F.M.1    Barber, J.L.2    Booij, K.3    Dachs, J.4    Lohmann, R.5    Jones, K.C.6
  • 54
    • 0032541122 scopus 로고    scopus 로고
    • 3Br estimated from the junge spatial variability relation
    • Colman, J. J.; Blake, D. R.; Rowland, F. S. Atmospheric residence time of CH3Br estimated from the Junge spatial variability relation. Science (Washington, D. C.) 1998, 281, 392-396. (Pubitemid 128665442)
    • (1998) Science , vol.281 , Issue.5375 , pp. 392-396
    • Colman, J.J.1    Blake, D.R.2    Rowland, F.S.3
  • 55
    • 63849153817 scopus 로고    scopus 로고
    • Atmospheric Chemistry of 4:2 Fluorotelomer Acrylate [C4F9CH2CH2OC(O)CH= CH2]: Kinetics, Mechanisms, and Products of Chlorine-Atom- And OH-Radical-Initiated Oxidation
    • Butt, C. M.; Young, C. J.; Mabury, S. A.; Hurley, M. D.; Wallington, T. J. Atmospheric Chemistry of 4:2 Fluorotelomer Acrylate [C4F9CH2CH2OC(O)CH=CH2]: Kinetics, Mechanisms, and Products of Chlorine-Atom- and OH-Radical-Initiated Oxidation. J. Phys. Chem. A 2009, 113, 3155-3161.
    • (2009) J. Phys. Chem. A , vol.113 , pp. 3155-3161
    • Butt, C.M.1    Young, C.J.2    Mabury, S.A.3    Hurley, M.D.4    Wallington, T.J.5


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