A 50-years record of DDT and HCH in lake sediment in King George Island, Antarctic

The Antarctic continent does not have stream–river drainage systems, Antarctic lakes are thus the main sinks for water and solutes from the surrounding environment. Depending on their origin, the presence of a perennial ice cover, exposed rocks and soils in the watershed, seabirds and distance from the sea, the water may show very different characteristics – from almost distilled to salt-rich brine which does not freeze in winter.
This dataset regards the accumulation flux profiles and temporal trends of organochlorine pesticides such as DDT and HCH in two lake cores from King George Island, West Antarctica. In the lake core sediments with glacier melt water input, the accumulation flux of DDT shows an abnormal peak around the 1980s in addition to the expected one in the 1960s. In the lake core sediments without glacier melt water input, the accumulation flux of DDT shows a gradual decline trend after the peak in 1960s. This striking difference in the DDT flux profiles between the two lake cores is most likely caused by the regional climate warming and the resulted discharge of the DDT stored in the Antarctic ice cap into the lakes in the Antarctic glacier frontier, as already reported in 1996 for PCBs.