Impact of season and location on the natural radioactivity in marine macroalgae (Gracilaria edulis) of coastal Tamil Nadu, India

Abstract

Gracilaria edulis, an edible red marine macro algae from three high background radiation areas (Arockiapuram, Kadiapattinam and Kurumpanai) on the southwest coast of Tamil Nadu, and one low background radiation area (Mandapam) on the southeast coast of Tamil Nadu, in India, were studied for variations in average gross alpha and beta radiation activities. Significant variations in average gross beta activities were observed while alpha activities showed only marginal variation. The average gross alpha activity was recorded high (61.51 Bq kg−1) during the post southwest monsoon season, while it recorded lowest (25.48 Bq kg−1) during the post northeast monsoon season. Average gross beta activity varied between seasons with the lowest level (211.55 Bq Kg−1) during post southwest monsoon season and the highest (413.33 Bq kg−1) during post northeast monsoon season. Among the four locations, the gross alpha activity was high (70.95 ± 26.74 Bq Kg−1) in Arockiapuram and low (18.74 ± 6.32 Bq Kg−1) in Mandapam, while the gross beta activity was high (442.25 ± 168.53 Bq Kg−1) in Kurumpanai and low (158.63 ± 34.37 Bq Kg−1) in Mandapam. Average gross alpha activity in G. edulis was found significantly varying in terms of locations, while average gross beta activity for the same species recorded significant seasonal variation.