DISTRIBUTION OF URANIUM IN URINE, HAIR AND NAILS IN RESIDENTS OF NISKA BANJA TOWN, A HIGH NATURAL BACKGROUND RADIATION AREA OF ERBIA

Quantification of uranium in human urine is a valuable technique for assessing occupant and public exposure to uranium. Human hair and nails can be considered as bio-indicators of the public exposure to certain natural radionuclides and toxic metals over a long period of months or even years. All urine, hair and nail samples were collected from a population of both sex aged from 40 to 87 years in Niška Banja (227 km south of Belgrade) with a high level of natural radioactivity (HLNRA), a suburban municipality of Serbia which located in the quaternary alluvium of River Nišava along the contact of the Koritnik limestone and travertine rock. Air dose rate in indoor environment has been measured. To assess and monitor the public exposure, urine samples for each subject (24 h period) were collected and concentration of uranium was analyzed using alpha-particle spectrometry. After addition of radioactive tracer U-232 and concentrated nitric acid, samples were evaporated to dryness. Residues were wet ashed with nitric acid and H2O2, radiochemical separationof uranium radioisotopes were performed by extraction chromatography using UTEVA resin. Uranium concentration in hair and nail samples from same subjects were analyzed using inductively coupled plasma mass spectrometry. Uranium concentrations in hair, nail and urine varied from 0.2 to77.1 ppb, 2.5 to 44.7 ppb, 54-730 ppb respectively. There was a large variation and may be due to geological origin and anthropogenic activities.9th International Conference on High Level Environmental Radiation Areas-For Understanding Chronic Low-Dose-Rate Radiation Exposure Health Effects and Social Impacts (ICHLERA 2018)