Flux of 210Pb, 137Cs, 239+240Pu, 238Pu, and 241Am in the Antarctic Peninsula area

210Pb, 137Cs, 239+240Pu, 238Pu, and 241Am were analysed in lichen, moss grass and soil samples, as well as in lake sediments, from the South Shetland Islands, the Antarctic, in order to evaluate the flux and deposition of these elements. 210Pb and 210Po and 137Cs were analysed in water, macroalgae and investigated in the Antarctic foodchain. Average inventory of the analysed radionuclides in 1988 is 210Pb (excess): 280±110 Bq m-2 (n=15), 137Cs: 155±95 Bq m-2 (n=19), 239+240Pu: 4.6±2.6 Bq m-2 (n=19), 238Pu: 0.95±0.5 Bq m-2 (n=19) and 241Am: 1.6±1.0 Bq m-2 (n=19). From the unsupported 210Pb it is calculated an annual deposition of 9±3 Bq m-2. The ratios 238Pu/239+240Pu and 241Am/239+240Pu of 0.21±0.04 and 0.35±0.08 respectively agrees well with expected values in this area. A significant difference in 137Cs/239+240Pu ratios between lichens and moss/grass/soil is observed. From one of the three studied lakes it is possible to perform 210Pb dating with reasonably accuracy showing an average annual accumulation of 45 g m-2. Activity concentrations of 137Cs in seals, penguins and fish from the Antarctic Peninsula area were about 0.2-0.9 Bq kg-1 dry weight, 0.1-1 Bq kg-1 and 3-4 Bq kg-1 respectively. The average activity concentration in water was 0.2±0.1 mBq 1-1. Activity concentration of 210Po were surprisingly high in liver and kidney of seals ranging from 50-250 Bq kg-1 and 30-200 Bq kg-1 respectively with a 210Po/210Pb ratio of 50-200. (LN) (20 refs.)