Baseline radionuclide concentration in selected marine organisms around the coastal areas of Ratnagiri and Sindhudurg districts, west coast of Maharashtra, India.

The present work deals with assessment of baseline radionuclide concentration in marine organisms around selected coasts of Maharashtra, India. This baseline study highlights concentrations of natural and fallout radionuclides in finfish and shellfish species found in the surrounding seawater. Water and fish samples were collected, processed, and analyzed for 238U, 226Ra, 228Ra, 232Th, 40K, and 137Cs by high-resolution gamma spectrometry. 238U, 226Ra, 228Ra, 232Th, 40K, and 137Cs concentrations were found to be in the range of ≤1.5, ≤2.0, ≤0.4, ≤1.5, ≤8.0 to 258, and ≤0.2 Bq/kg, respectively. The seasonal study revealed the maximum concentration in premonsoon season. Activity concentrations were higher in pelagic fish than those in demersal fish. A higher concentration factor was reported in shellfish than in finfish.

Radiological characterisation of synthetic rutile using HPGe gamma spectrometry.

This paper discusses the radiological characterisation of synthetic rutile, which is the source material for the production of titanium. The natural radioactivity due to uranium ((238)U), thorium ((232)Th) series radionuclides and potassium ((40)K) was measured in synthetic rutile samples of a production plant in Tamil Nadu, India. n-type high-purity germanium-coupled gamma spectrometry was used for the analysis. It is observed that thorium is more abundant than any other radionuclide, which is due to the monazite present in the primary sand. The activity index (I) evaluated from the radioactivity concentrations of (226)Ra, (232)Th and (40)K of the analysed samples is found to be well below the recommended levels. This study shows that the use of synthetic rutile from Tamil Nadu, India, for the manufacture of building materials will not pose any increased radiation exposure to the public beyond the dose criterion of the European Union.

Spatial distribution of uranium and thorium in the surface soil around proposed uranium mining site at Lambapur and its vertical profile in the Nagarjuna Sagar Dam.

The understanding and evaluation of the possible interactions of various naturally occurring radionuclides in the world's third largest man-made dam, Nagarjuna Sagar located in Andhra Pradesh, India and built on river Krishna assumed significance with the finding of uranium deposits in locations near the dam. For the present work, surface soil samples from the mineralized area of Lambapur, Mallapuram, Peddagattu and sediment core samples from the Nagarjuna Sagar dam were analyzed for naturally occurring radionuclides namely uranium and thorium using gamma spectrometric technique. Also toxic elements lead and chromium were analysed by the Energy Dispersive X-ray Fluorescence Spectrometer (EDXRF) technique. Surface soil samples show a variation from 25 to 291 Bq/kg (2.02-23.5 mg/kg) for (238)U and 32-311 Bq/kg (7.9-76.9 mg/kg) for (232)Th. U/Th concentration ratio in surface soil samples ranged from 0.19 to 0.31 and was found comparable with the nation wise average of 0.26. The study of sediment core samples reflected higher U/Th concentration ratio of 0.30-0.33 in the bottom section of the core as compared to 0.22-0.25 in the upper section. The concentration ratio in the upper section of the core was similar to the ratio 0.23 found in the western Deccan Basalt region through which the river originates. A higher concentration of lead and chromium was observed in the upper section of the core compared to bottom section indicating the impact of river input on the geochemical character of dam sediment.