Change search
ReferencesLink to record
Permanent link

Direct link
Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways
Umeå University, Faculty of Science and Technology, Department of Chemistry. Air Quality Processes Research Section, Environment Canada. (Arcum)
Show others and affiliations
2015 (English)In: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 15, no 3, 1411-1420 p.Article in journal (Refereed) Published
Abstract [en]

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.

Place, publisher, year, edition, pages
2015. Vol. 15, no 3, 1411-1420 p.
National Category
Organic Chemistry
URN: urn:nbn:se:umu:diva-101416DOI: 10.5194/acp-15-1411-2015ISI: 000349799500017OAI: diva2:808965
Available from: 2015-04-30 Created: 2015-03-30 Last updated: 2016-05-18Bibliographically approved

Open Access in DiVA

fulltext(1959 kB)60 downloads
File information
File name FULLTEXT01.pdfFile size 1959 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full text

Search in DiVA

By author/editor
Bidleman, Terry Frank
By organisation
Department of Chemistry
In the same journal
Atmospheric Chemistry And Physics
Organic Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 60 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 136 hits
ReferencesLink to record
Permanent link

Direct link