Radium-228 in some bivalve molluscs from Gulf of Mannar, India

This paper presents the results of the measurements of beta emitting natural radionuclides 228Ra in water, sediment and some bivalve molluscs of Gulf of Mannar, which is a marine province of the south east coast of India. The dissolved 228Ra concentration in sea water ranged from 4.10 to 5.20 mBq l1 (mean : 4.5 mBql-1) and in sediment samples ranged from 30.70 to 42.50 Bq kg-1 (mean: 36.83 Bq kg-1). The 228Ra concentrations in water and sediments gradually decline from Cape Comorin to Mandapam. The results further indicated the differential accumulation of the radionuclide with enhanced bioaccumulation in shells. The brown mussel Perna indica was identified to accumulate higher concentration of228 Ra in their soft tissues (6.30-7.70 Bq kg-1 wet) and shell (21.06-26.03 Bq kg-1 wet) suggesting that they could serve as a biomonitor of 228Ra radionuclide in the marine environment. (author)