Cs-137 in biota and sediment samples from Turkish coast of the Black Sea, 1997-1998

During the periods of 1997-1998, macroalgae, sea snail, mussel, fish and se diment samples were collected from different stations at Turkish Black ;Sea coast in order to determine activity levels of Cs-137 radionuclide. Cs-137 activity in the tested algae species and in soft parts of mussel and sea s nail, were found to be below the lower limit of detection. On the other han d, the Cs-137 concentration in muscle tissue of the sea snail samples were found from 6 +/- 2 to 19 +/- 7 Bq.kg(-1) dry weight. The range of the Cs-13 7 concentration in anchovy fish muscles were found between 4 +/- 2 - 10 +/- 5 Bq.kg(-1) dry weight. The Cs-137 concentration in the whiting fish muscl e was found below the lower limit of detection. However, this activity foun d in shad fish muscle to be 25 +/- 10 Bq.kg(-1) dry weight. The concentrati ons of the Cs-137 activity in the sediment samples proved that the eastern region of the Black Sea was affected by Chernobyl at a very high degree com pared with the western part. The measured U-238, Th-232 and K-40 concentrat ions in sediment samples are within the range of the cited values in the pr evious works at the Turkish Black Sea coast.