Geochemometrics of primordial radionuclides and their potential radiological risk in coastal sediments of Southeast Coast of India

Abstract

In recent years, the contamination of the earth's materials with radioactive elements as naturally occurring radioactive material has been a source of concern. This study is aimed at the environmental radioactivity of beach sediments and the gamma dose levels along the south-eastern coastal region of the Indian subcontinent, from the Palar River mouth (Kadalur Kuppam) to the Pulicat Lake or Pazhaverkadu coast. Furthermore, to analyze the gamma dosage level, as well as the spatial variation of the activity concentrations of 238U, 232Th, and 4 K, as well as the acid-leachable trace elements Ni, Pb, Mn, Zn, Cu, Co, Fe, and Cr in coastal sediments. In addition, radiological risk and hazard indices are assessed in the study domain. The MiniTRACE CSDF survey meter was used to determine the ambient gamma dose level and the activity concentration of primordial radionuclides (238U, 232Th, and 4 K) was quantified using gamma-ray spectroscopy with a NaI (Tl) detector, as well as trace elements studied in atomic absorption spectroscopy. The primordial radionuclides activity concentration (238U, 232Th, and 4 K) in collected coastal sediments of the proposed region were found in the range of ≤3–1953, ≤3–1180, and 41–753 Bq/kg, respectively. The annual effective dose rate was found in the order of 4 K > 232Th > 238U. Based on the geochemometric approach, the data collected for various radiological parameters were combined with radiological risk indices, and trace element concentrations were compared on a regional and global scale. The current study could provide a new research pathway in the areas of coastal monitoring, environmental health, and radiation safety measures.