241Pu concentration in southern Baltic Sea ecosystem

Pu-241 concentrations were calculated indirectly in different compartments of the southern Baltic ecosystem by the activity measurements of Am-241 isotope from the increase of the beta-emitting Pu-241 at 16-18 years after the Chernobyl accident. Enhanced levels of Pu-241 were observed in all analyzed samples. Maximum values (0.408 and 0.367 mBq.g(-1) d.w.) of the estimated Pu-241 concentrations were found in sediments of Internal Puck Bay and Gdanask Bay, respectively, and in the suspended matter from water of Gdanask Bay (77.8 mBq.g(-1) d.w.). The highest Pu-241/Pu239+240 activity ratio was found in the suspended matter (1500) and water (140). The Pu-241 activity of the air dust was very high in April 1986, 3643 +/- 34.3 mBq.g(-1) d.w., and the Pu-241/Pu239+240 activity ratio was 56, but the highest Pu-241/Pu239+240 activity ratio of the air dust was measured in August. Then the Pu-241 concentration in air dust decreased quickly to values similar to those before the Chernobyl accident. This study provides new data for the Pu-241 concentrations in various compartments of the Baltic Sea ecosystem.