Study of distribution of radionuclides in cultivated land in and around chikmagalur, Karnataka, India

Distribution of natural radioactivity in different geological formations and their environmental risk assessment in Malaysia

“…Generally, igneous rocks have the ability to accumulate large incompatible nuclei in different rock-forming minerals and accessory minerals which leads to granitoid felsic igneous rocks having potential for radioactive isotopes like U, Th and 40 K (Younis et al 2022 ). The high abundance of rock-forming minerals in granitoid such as feldspar and micas contributes to a high level of 40 K and a higher proportion of radionuclide-bearing minerals compared to other geological units, and this leads to igneous rocks having significantly higher natural radioactivity (Manjunatha et al 2013 ). In this study, mafic igneous rocks were found to have very low natural radioactivity (0.18 to 0.63 CPS) mainly because of their lack of potassium-bearing minerals and predominantly low or non-radioactive minerals such as pyroxene, olivine and plagioclase feldspars (Schön 2011 ).…”

“…Abdulqader et al ( 2018 ) also observed that the schist sample with higher graphitic content also contains more uranium. However, quartz in metamorphic rocks can show insignificant radioactivity (Manjunatha et al 2013 ). In this study, metamorphic rocks such as argillite and metasandstone, including metasedimentary rocks, were found to contain a considerable amount of radionuclide-bearing minerals and potassium minerals that contributed to medium to high radioactivity (0.4 to 0.71 CPS on average).…”

“…The distribution and the concentration of primordial radionuclides, U, Th and 40 K determine the natural radioactivity of a geological unit, related to the minerals it contains (Chiozzi et al 2007 ). U, Th decay series and 40 K are primary natural sources of ionising radiation in all types of geological units, such as igneous, metamorphic, sedimentary rocks and soils (Manjunatha et al 2013 ; Uyanik et al 2015 ; Lolila and Mazunga 2023 ; Lakshmi et al 2024 ). The potential naturally occurring radioactive elements such as Ca, V, Ge, Se, Rb, Zr, Mo, Cd, In, Te, La, Ne, Sm, Eu, Gd, Lu, Hf, W, Rh, Pt and Bi either have a relatively longer half-life or are less abundant; thus, they are expected to have only minor impact on natural radiation (Asimov 1953 ).…”