A study of metal and metalloid contaminant availability in Antarctic marine sediments

• Published in: Chemosphere (Oxford) Vol. 67; no. 10; pp. 1967 - 1974
• Main Authors: Larner, Bronwyn L., Seen, Andrew J., Palmer, Anne S., Snape, Ian
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.05.2007; Elsevier
• Subjects: Antarctic Regions; Applied sciences; Arsenic - analysis; AVS; BCR sequential extraction; Biological and physicochemical properties of pollutants. Interaction in the soil; Brown Bay; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental Monitoring - methods; Exact sciences and technology; Geologic Sediments - chemistry; Metal and metalloid contaminants; Metals - analysis; Partial extraction; Pollution; Pollution, environment geology; Soil and sediments pollution; Thala; Trace Elements - analysis; Water Pollutants, Chemical - analysis; Antarctica; Southern Ocean; Antarctic Regions; Antarctica, Wilkes Land, Casey Stn; Partial extraction; Brown Bay; Metal and metalloid contaminants; BCR sequential extraction; AVS; Marine sediments; Pollutant behavior; Geochemistry; Coastal zone; Heavy metal; Trace element; Sulfides; Pollution; Limiting factor; Bay; Speciation
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2006.11.059

Previous studies of impacted sites near Casey Station, Antarctica, have revealed elevated concentrations of metals and metalloids, particularly Cd, Cu, Fe, Pb, Sn and Zn in marine sediments. However, attempts to understand the availability and mobility of contaminant elements have not provided a true understanding of speciation. The current work shows, for the first time, that sediments in Brown Bay, an embayment adjacent to the Thala Valley waste disposal site, have elevated concentrations of sulfide, well in excess of that required to bind contaminant metals such as Cd, Cu, Pb and Zn. Furthermore, sediment characterisation using the BCR sequential extraction scheme has shown metal partitioning consistent with sulfides being the controlling factor in metal availability, thus explaining the low porewater concentrations of these metals. The speciation of Sn in Brown Bay, however, is still unclear with the BCR sequential extraction scheme partitioning Sn predominantly into the residual fraction despite Sn being readily extracted by dilute HCl.