Natural radionuclide and toxic metal contents of rock salts from mines in Central Anatolia of Turkey

Abstract

In this study, the natural radionuclide andpotentially toxic heavy metal contents of rock salt samples collected from three different salt mines located in Çankırı city in the Central Anatolia of Turkey were determined using gamma-ray and X-ray fluorescence (XRF) spectrometry.Also, concentrations of radionuclides and heavy metalsin different table salts (sea, lake, and Himalayan) consumed in Turkey were determined to compare with rock salt. The average activity concentration of 226Ra, 232Th and 40K measured in rock salt samples were found as 1.4, 5.6 and 34.0 Bqkg−1, respectively.The average concentration of Ti, Mn, Fe, Ni, Cu, Zn, Zr and Pb in rock salt samples was analysed as 64.8, 12.9, 504.6, 3.6, 1.8, 2.0, 1.6 and 1.4 µgg−1, respectively. The concentration of Cr, Co, As, Cd, and Hg was below the detection limits.Also, the total annual effective dose (AED) and daily intake of potentially toxic heavy metals due to an intake of the radionuclides and heavy metals from rock salt samples wereestimated. The average value of AED was estimated as 8.4 μSv, which is significantly lower than the average annual effective dose of 290 μSv received by the ingestion of natural radionuclides.