Title: | Time trends of selected persistent organic pollutants in lake sediments from Greenland |
Author(s): | Malmquist C; Bindler R; Renberg I; van Bavel B; Karlsson E; Anderson NJ; Tysklind M; |
Address: | "Environmental Change Assessment, Department of Ecology and Environmental Science, Umea University, SE-901 87 Umea, Sweden. Carola.Malmquist@eg.umu.se" |
ISSN/ISBN: | 0013-936X (Print) 0013-936X (Linking) |
Abstract: | "Sediments from seven lakes in West Greenland were used as natural archives to study past and present levels of PCBs (polychlorinated biphenyls, tri- to decachlorinated), tetra-BDE #47 (2,2',4,4'-bromodiphenyl ether), chlordane (cis- and trans-octachlordane) and HxCBz (hexachlorobenzene). The concentrations found are lower than or comparable to concentrations found in sediments from other Arctic regions and one to 2 orders of magnitude lower than concentrations typically found in sediments at lower latitudes. The observed temporal trends (direct and indirect dating) show a decreasing total PCB concentration. Even though local contamination sources exist, the POP deposition in the studied area is most likely a result from long-range transport. The hypothesis about 'cold condensation' suggests a latitudinal fractionation to occur between different volatile compounds during the transport toward the pole. In this study a time delay in the deposition for the low-chlorinated PCBs (tri- and tetrachlorinated), compared to their emission histories and compared to higher chlorinated PCBs, was indicated. Although very low tetra-BDE #47 concentrations are observed in this study, there are indications for an increasing concentration in recent sediment layers that may reflect increasing environmental concentrations at lower latitudes. The investigated pesticides are still in use at lower latitudes, however neither chlordane nor HxCBz show any distinct temporal trend of increasing or decreasing concentration toward the sediment surface" |
Keywords: | "Chlordan/*analysis Environmental Monitoring Environmental Pollutants/*analysis Fungicides, Industrial/*analysis Geologic Sediments/*chemistry Greenland Hexachlorobenzene/*analysis Insecticides/*analysis Polychlorinated Biphenyls/*analysis Temperature Time;" |
Notes: | "MedlineMalmquist, Carola Bindler, Richard Renberg, Ingemar van Bavel, Bert Karlsson, Edvard Anderson, N John Tysklind, Mats eng Research Support, Non-U.S. Gov't 2003/10/24 Environ Sci Technol. 2003 Oct 1; 37(19):4319-24. doi: 10.1021/es020250a" |