210Po content in sea water and its accumulation in southern Baltic plankton

This paper presents the results of an investigation from 1980 to 1985 on the content of ²¹⁰Po in sea water and its accumulation in southern Baltic plankton. The mean value of the ²¹⁰Po concentration in sea water has been determined to be about 0.5 mBq dm^-3, with the proportion of the dissolved forms being ca 80%. It has been proved that ²¹⁰Po is accumulated by plankton organisms. The mean ²¹⁰Po concentration factors calculated on the basis of its content in plankton fall within the range from 5×10³ to 4.2×10⁴ and increase as follows: phytoplankton210Po concentration in mesozooplankton collected at the Slupsk Trough and the Gdask Basin have been observed. The above differences have been related to intense blue-green alga blooming in the Gdask Basin.