Studies on the distribution of 210Po and 210Pb in the ecosystem of Point Calimere Coast (Palk Strait), India

A systematic study on the natural radionuclides such as 210Po and 210Pb in the environmental matrices of Point Calimere ecosystem has been undertaken to establish a baseline data on the radiation profile of Point Calimere environment. The environmental samples such as water, sediment and biota (seaweeds, crustaceans, molluscs and fish) have been subjected to analyses. It has been observed that the concentration of 210Po and 210Pb in the water samples of Point Calimere to be 0.5 mBq/l and 1.3 mBq/l, respectively. The soft tissues of the organisms accumulated higher 210Po content while shells and bones contained more 210Pb. The bivalve molluscs Meretrix casta have been identified to accumulate higher concentration of 210Po suggesting that they could serve as bio-indicator of radionuclides like 210Po in the Point Calimere ecosystem. The concentration factor of 210Po for the biotic components ranged from approximately 10(3) to 10(6) while for 210Pb it ranged from approximately 10(3) to 10(5).     

Gamma dose measurement in dwellings of Agastheeswaram Taluk of Kanyakumari district, lying 30 km Radius from Kudankulam nuclear power plant site

Most of the building materials contain naturally occurring radioactive elements, the most important of which are potassium ⁴⁰K and the members of two natural radioactive series, which can be represented by the isotopes of thorium ²³²Th and Uranium ²³⁸U. The presence of these radioisotopes in the materials causes external exposure to the people who live in the building. In addition, the disintegration of Uranium ²³⁸U increases the concentration of radon gas ²²²Rn and of its daughters in the house. So a systematic indoor gamma dose measurement has been performed in the dwellings of Agastheeswaram Taluk of Kanyakumari district, which is lying within the 30 km radius from the upcoming Kudankulam nuclear power plant site. The geometric mean of annual absorbed dose from gamma radiation in dwellings has been found to be 278 nGyh⁻¹. The seasonal variation of indoor gamma dose measurements has also been studied. Significant differences have been observed in dwellings built of different materials such as concrete, tiled, etc.