ASSESSMENT OF ENVIRONMENTAL RADIOACTIVITY AND HEALTH HAZARD AT STARA PLANINA REGION

The aim of the study was to evaluate the potential risks of radiation near abandoned uranium mines, tailing dumps, or uranium deposits on Mountain Stara Planina, Serbia. For risk assessment several parameters were determined: radium equivalent activity, Ra-eq, external hazard index, H-ex, gamma radiation absorbed dose rate, D, annual effective dose on background outdoor gamma exposure, AED(outdoor), and excess lifetime cancer risk, ELCR. Obtained results showed that all the samples, except one, have the Ra-eq value up to two times higher than the reference limit. The Ra-eq of the sample from the Mezdreja mine tailings was increased by almost eight times. The value of H-ex followed the same pattern as Ra-eq. All the investigated localities have increased D values, while all the samples have shown the moderately low AED(outdoor), except Mezdreja mine tailings that have 5.5-2.8 times higher dose relative to the world's average. ELCR at the Mezdreja mine tailings is 4.58 times higher than the world's average of 1.45.10(-3). In the con text of human activity in the area of Stara Planina such as different kinds of tour ism, livestock breeding, dairy products, and herbal manufacturing, etc. there is a need for detailed analysis in order to evaluate potential human exposure and health impacts.