The human biomonitoring study in Serbia: Background levels for arsenic, cadmium, lead, thorium and uranium in the whole blood of adult Serbian population
The purpose of this study was to establish reference values (RVs) for the occupationally- and environmentally-important toxic elements in the whole blood of adult Serbian population for the first time. Contaminated drinking water with arsenic, high share of smokers in the country, removing tetraethyl lead from the gasoline and war attack at the end of the twentieth century were some of the reasons to provide background information for arsenic (As), cadmium (Cd), lead (Pb), thorium (Th), and uranium (U) in the blood of the Serbian population. The whole blood samples were collected from the healthy respondents living in the Belgrade and surrounding areas of the capital (n = 305; w/m ratio = 154/151; mean age: 41 ± 2). The concentrations of toxic metals were determined by inductively coupled plasma-mass spectrometry (ICP-MS). Reference values were estimated as the lower limit (LL) and upper limit (UL) of the 95% confidence interval (CI), together with the selected percentiles (P2.5-P97.5). The obtained geometric mean (GM) for As, Cd, Pb, Th, and U were: 0.50 ng/g, 0.32 ng/g, 20.94 ng/g, 0.30 ng/g, and 0.06 ng/g, respectively. The influences of age, sex and lifestyle on results were considered. Women have significantly higher levels of Cd and Th than men. The increased level of Th was observed in the aged group below 40 years, while smokers had significantly higher levels of Pb and double higher level of Cd in the blood than non-smokers (p < 0.05). In comparison with other population groups worldwide, the Serbian population had significantly higher levels of Th and U (up to 100 times higher). These findings could contribute to better understanding of the molecular basis for the development of various health hazards, including the increased incidence of cancer among the Serbian population which need be confirmed by clinical studies.