Bioaccumulation of 239+240Pu in benthic organisms crab (Scylla serrata) and arca (Anadara granosa) : a case study from Trombay

The study presents the concentration of (239+240)Pu in various size groups of crab (SCYLLA SERRATA) and arca (ANADARA GRANOSA). Around 96 crabs and 650 arcas were harvested from the Mumbai Harbour Bay. Crabs and arcas were grouped in different size groups as per their widths. The maximum concentration 239+240Pu is observed in case of crab for the lowest size group whereas for arca the same is observed in the highest size group. This difference in the uptake of (239+240)Pu is attributed to the difference in metabolic functions of the two species. Bio-accumulation factor (Bp) values in case of crab flesh ranged between 70 to 1140 kg-1 with a GM value of 180 and in arca the value ranged between 6 to 60 l kg-1 with a GM of 20. The values for shell were higher by factors of 2 to 9 in case of crab and 3 to 22 in case of arca. The smallest size group of crab shows maximum Bp value whereas for arca maximum Bp is observed for maximum size group. (author)