Lead contamination of subarctic lakes and its response to reduced atmospheric fallout:Can the recovery process be counteracted by the ongoing Climate change?

• Published in: Environmental Science & Technology
• Main Authors: Jonatan, Klaminder, Dan, Hammarlund, Ulla, Kokfelt, Vonk And, Jorien E., Christian, Bigler
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2010
• Subjects: permafrost; Subarctic
• Online Access: https://research.vu.nl/en/publications/1f8acfbc-942c-416e-9439-93b0437bc4ce; https://doi.org/10.1021/es903025z; http://hdl.handle.net/1871.1/1f8acfbc-942c-416e-9439-93b0437bc4ce; http://www.scopus.com/inward/record.url?scp=77950411959&partnerID=8YFLogxK; http://www.scopus.com/inward/citedby.url?scp=77950411959&partnerID=8YFLogxK

Can a climate-triggered export of old contaminants from the soil alter the lead (Pb) contaminant burden of subarctic lakes? To address this question, we reconstructed the pollution history of three high latitude lakes situated in a region where a recent climatic shift has occurred. Dated sediment records were used as archives of past Pb inputs to the lakes, where the difference in the 206 Pb/ 207 Pb ratio between atmospheric contaminants ( 206 Pb/ 207 Pb ratio <1.16) and geogenic Pb in the catchment soil ( 206 Pb/ 207 Pb ratio > 1.22) were used to trace fluxes of Pb contaminants. Lead contaminants were found in sediments deposited since Roman times. A significant export of Pb from the soil contaminant pool is indicated in two of the lakes surrounded by near-shore permafrost soils. Here, levels of Pb contaminants and 206 Pb/ 207 Pb ratios of sediments deposited after the 1970s appear not to have been strongly affected by the ≥ 90% reduction in atmospheric deposition rates and increasing 206 Pb/ 207 Pb ratios of atmospheric Pb since the 1990s. We concluded that soil processes stimulated by the ongoing climate change at high latitudes might work counteractive to efforts to reduce contaminant levels in subarctic lakes.