Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways
Air samples collected during 1994-2000 at the Canadian Arctic air monitoring station Alert (82 degrees 30'N, 62 degrees 20'W) were analysed by enantiospecific gas chromatography-mass spectrometry for alpha-hexachlorocyclohexane (alpha-HCH), trans-chlordane (TC) and cis-chlordane (CC). Resu...
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Umeå universitet, Kemiska institutionen
2015
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ftumeauniv:oai:DiVA.org:umu-101416 2023-10-09T21:48:41+02:00 Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways Bidleman, Terry Frank Jantunen, L. M. Hung, H. Ma, J. Stern, G. A. Rosenberg, B. Racine, J. 2015 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-101416 https://doi.org/10.5194/acp-15-1411-2015 eng eng Umeå universitet, Kemiska institutionen Air Quality Processes Research Section, Environment Canada Atmospheric Chemistry And Physics, 1680-7316, 2015, 15:3, s. 1411-1420 http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-101416 doi:10.5194/acp-15-1411-2015 ISI:000349799500017 Scopus 2-s2.0-84922646712 info:eu-repo/semantics/openAccess Organic Chemistry Organisk kemi Article in journal info:eu-repo/semantics/article text 2015 ftumeauniv https://doi.org/10.5194/acp-15-1411-2015 2023-09-22T13:57:46Z Air samples collected during 1994-2000 at the Canadian Arctic air monitoring station Alert (82 degrees 30'N, 62 degrees 20'W) were analysed by enantiospecific gas chromatography-mass spectrometry for alpha-hexachlorocyclohexane (alpha-HCH), trans-chlordane (TC) and cis-chlordane (CC). Results were expressed as enantiomer fractions (EF = peak areas of (+)/[(+) + (-)] enantiomers), where EFs = 0.5, <0.5 and >0.5 indicate racemic composition, and preferential depletion of (+) and (-) enantiomers, respectively. Long-term average EFs were close to racemic values for alpha-HCH (0.504 +/- 0.004, n = 197) and CC (0.505 +/- 0.004, n = 162), and deviated farther from racemic for TC (0.470 +/- 0.013, n = 165). Digital filtration analysis revealed annual cycles of lower alpha-HCH EFs in summer-fall and higher EFs in winter-spring. These cycles suggest volatilization of partially degraded alpha-HCH with EF < 0.5 from open water and advection to Alert during the warm season, and background transport of alpha-HCH with EF > 0.5 during the cold season. The contribution of sea-volatilized alpha-HCH was only 11% at Alert, vs. 32% at Resolute Bay (74.68 degrees N, 94.90 degrees W) in 1999. EFs of TC also followed annual cycles of lower and higher values in the warm and cold seasons. These were in phase with low and high cycles of the TC / CC ratio (expressed as F-TC = TC/(TC + CC)), which suggests greater contribution of microbially "weathered" TC in summer-fall versus winter-spring. CC was closer to racemic than TC and displayed seasonal cycles only in 1997-1998. EF profiles are likely to change with rising contribution of secondary emission sources, weathering of residues in the environment, and loss of ice cover in the Arctic. Enantiomer-specific analysis could provide added forensic capability to air monitoring programs. Article in Journal/Newspaper Arctic Resolute Bay Umeå University: Publications (DiVA) Arctic Resolute Bay ENVELOPE(-94.842,-94.842,74.677,74.677) Atmospheric Chemistry and Physics 15 3 1411 1420 |
institution |
Open Polar |
collection |
Umeå University: Publications (DiVA) |
op_collection_id |
ftumeauniv |
language |
English |
topic |
Organic Chemistry Organisk kemi |
spellingShingle |
Organic Chemistry Organisk kemi Bidleman, Terry Frank Jantunen, L. M. Hung, H. Ma, J. Stern, G. A. Rosenberg, B. Racine, J. Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways |
topic_facet |
Organic Chemistry Organisk kemi |
description |
Air samples collected during 1994-2000 at the Canadian Arctic air monitoring station Alert (82 degrees 30'N, 62 degrees 20'W) were analysed by enantiospecific gas chromatography-mass spectrometry for alpha-hexachlorocyclohexane (alpha-HCH), trans-chlordane (TC) and cis-chlordane (CC). Results were expressed as enantiomer fractions (EF = peak areas of (+)/[(+) + (-)] enantiomers), where EFs = 0.5, <0.5 and >0.5 indicate racemic composition, and preferential depletion of (+) and (-) enantiomers, respectively. Long-term average EFs were close to racemic values for alpha-HCH (0.504 +/- 0.004, n = 197) and CC (0.505 +/- 0.004, n = 162), and deviated farther from racemic for TC (0.470 +/- 0.013, n = 165). Digital filtration analysis revealed annual cycles of lower alpha-HCH EFs in summer-fall and higher EFs in winter-spring. These cycles suggest volatilization of partially degraded alpha-HCH with EF < 0.5 from open water and advection to Alert during the warm season, and background transport of alpha-HCH with EF > 0.5 during the cold season. The contribution of sea-volatilized alpha-HCH was only 11% at Alert, vs. 32% at Resolute Bay (74.68 degrees N, 94.90 degrees W) in 1999. EFs of TC also followed annual cycles of lower and higher values in the warm and cold seasons. These were in phase with low and high cycles of the TC / CC ratio (expressed as F-TC = TC/(TC + CC)), which suggests greater contribution of microbially "weathered" TC in summer-fall versus winter-spring. CC was closer to racemic than TC and displayed seasonal cycles only in 1997-1998. EF profiles are likely to change with rising contribution of secondary emission sources, weathering of residues in the environment, and loss of ice cover in the Arctic. Enantiomer-specific analysis could provide added forensic capability to air monitoring programs. |
format |
Article in Journal/Newspaper |
author |
Bidleman, Terry Frank Jantunen, L. M. Hung, H. Ma, J. Stern, G. A. Rosenberg, B. Racine, J. |
author_facet |
Bidleman, Terry Frank Jantunen, L. M. Hung, H. Ma, J. Stern, G. A. Rosenberg, B. Racine, J. |
author_sort |
Bidleman, Terry Frank |
title |
Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways |
title_short |
Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways |
title_full |
Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways |
title_fullStr |
Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways |
title_full_unstemmed |
Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways |
title_sort |
annual cycles of organochlorine pesticide enantiomers in arctic air suggest changing sources and pathways |
publisher |
Umeå universitet, Kemiska institutionen |
publishDate |
2015 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-101416 https://doi.org/10.5194/acp-15-1411-2015 |
long_lat |
ENVELOPE(-94.842,-94.842,74.677,74.677) |
geographic |
Arctic Resolute Bay |
geographic_facet |
Arctic Resolute Bay |
genre |
Arctic Resolute Bay |
genre_facet |
Arctic Resolute Bay |
op_relation |
Atmospheric Chemistry And Physics, 1680-7316, 2015, 15:3, s. 1411-1420 http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-101416 doi:10.5194/acp-15-1411-2015 ISI:000349799500017 Scopus 2-s2.0-84922646712 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/acp-15-1411-2015 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
15 |
container_issue |
3 |
container_start_page |
1411 |
op_container_end_page |
1420 |
_version_ |
1779311770057310208 |