Bioaccumulation of Pb-210 in the Kaveri River ecosystem, India

Data on the concentrations of Pb-210 in water, sediment and biota (plankton, weed, snail, bivalve, prawn and fish) of the Kaveri River ecosystem at Tiruchirappalli in South India are presented. The highest level of Pb-210 activity was observed in the sediment (15.5 Bq kg(-1) dry) and the lowest activity in water (2.7 mBq l(-1)). The root of the aquatic weed, Eichhornia crassipes showed a higher activity (1.17 Bq kg(-1) wet) than its shoot (0.22 Bq kg(-1) wet). Among the biotic components, the shells and bones of animals accumulated higher Pb-210 than their tissues and muscle. Among animals, the freshwater mussel, Lamellidens marginalis was identified to accumulate more Pb-210 in its soft tissues (0.79 Bq kg(-1) wet) and shell (6.55 Bq kg(-1) wet) than prawns (muscle: 0.65 Bq kg(-1) wet; exoskeleton. 1.06 Bq kg(-1) wet) and fish (muscle. 0.24 Bq kg(-1) wet; bone. 1.37 Bq kg(-1) wet). The concentration factors (CFs) of Pb-210 in biotic components ranged from similar to 10(1) to similar to 10(3) with higher CFs observed for shells and bones, It is shown that Pb-210 undergoes a seasonal variation in surface deposition with minimum values in summer and maximum values in winter. The significance of the results of Pb-210 in the abiotic and biotic environment of Kaveri River is discussed. (C) 1997 Elsevier Science Ltd.