Search

Measurements of radon activity concentrations have been conducted in public kindergartens, primary, and secondary schools in Kragujevac City. This study represents the first step towards radon mapping of Central Serbia. Passive discriminative radon/thoron detectors (so called UFO) were used for monitoring. The radon calibration coefficient of 0.026 (track/cm2)/(Bq m−3 day) was calculated by exposing the UFO detectors in a Rn chamber monitored by a RAD7 device. The Rn concentration was in the range of 27-145 Bq m−3 in kindergartens and 25-86 Bq m−3 in schools. The value of the arithmetic mean was 59.6 Bq m−3 and the standard deviation was 25.6 Bq m−3. The distribution of the results was well fitted by log-normal function. No significant correlation between measured activity concentrations and periods of building constructions was found. [ABSTRACT FROM AUTHOR]

After NATO bombing of Serbia in 1999, UNEP has identified Kragujevac as one of the four heavily polluted environmental "hot spots". Damaging of industrial and military targets caused the release of substantial amounts of hazardous chemical substances into the environment. This study was conducted in order to access the exposure of residents of Kragujevac city to persistent soil pollutants, twenty years after NATO air campaign. The paper reports the results of measuring radionuclides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, and Hg) in soil samples collected from two depths (0–15 cm and 15–30 cm) at 30 locations along the riverbank of the Lepenica River. The average specific activities of 226Ra, 232Th, 40K and 137Cs were comparable to average worldwide values; excess lifetime cancer risk (ELCR) from natural radionuclides ranged from 1.1·10−4 to 3.3·10−4. The measured concentrations of As, Co, Cr, Cu, and Ni exceeded the limit values in most of the samples. Non-carcinogenic risk (hazard quotient and hazard index) and carcinogenic risk from heavy metals were assessed. Total hazard index was 0.257 and 2.16 for adults and children, respectively. Sum of measured PAHs ranged from 110 to 1026 μg kg−1. Sum of PCBs exceeded the limit value of 20 μg kg−1 in all samples (it ranged from 48.8 to 196.8 μg kg−1), but it was still below the remediation level. The differences between two layers with respect to all measured variables were not statistically significant. Image 1 • Soil in a "hot spot" area was investigated twenty years after NATO bombing. • Significant contamination by PCBs was observed. • As, Co, Cr, Cu, and Ni exceed the limit values. • PAHs follow anthropogenic pattern and have pyrogenic origin. • Activities of 226Ra, 232Th, 4 K and 137Cs are comparable to worldwide averages. [ABSTRACT FROM AUTHOR]