Assessment of radionuclide concentration in three crustaceans species of the bay of Bengal

Abstract

The natural (226 Ra, 228 Th, 232 Th and 40 K) and anthropogenic (137 Cs) radionuclides concentrations in three crustaceans species (Penaeus monodon , Metapenaeus monoceros and Panulirus versicolor ), collected from the bay of Bengal, were determined with an aim of assessing any internal radiation hazard due to consumption of the shell fishes and establishing a database for radioactivity levels of the species. Very low level of radioactivity was observed in all the species. The average activity of 226 Ra observed in P. monodon was 1.21 ± 0.27 Bq kg–1 fw; in M. monoceros was 0.70 ± 0.08 Bq kg–1 fw, and in Panulirus versicolor was 1.04 ± 0.09 Bq kg–1 fw. The activity of 232 Th observed in these species was 1.30 ± 0.37, 0.76 ± 0.34 and 1.32 ± 0.70 Bq kg–1 fw, and 228 Th was 0.55 ± 0.26, 0.31 ± 0.14 and 0.74 ± 0.22 Bq kg–1 fw, respectively. The average activity of 40 K observed in these species was 12.56 ± 1.18, 6.38 ± 1.02 and 10.07 ± 1.52 Bq kg–1 fw, respectively. The activity of radiocaesium (137 Cs) was below detection limit. The results indicate that the natural and artificial radionuclides observed in three crustaceans species are safe for human health. A significant relationship was observed between 226 Ra and 232 Th in both the P. monodon (r = 0.839, p ≤ 0.05, df = 4) and the Panulirus versicolor (r = 0.906, p ≤ 0.05, df = 4).