Selenium in soil, grass, and human serum in the Zlatibor mountain area (Serbia): geomedical aspects.

The Zlatibor district in Serbia has lower mortality rates of malignant and cardiovascular diseases (CVD) compared with other regions in Serbia. To better understand the influence of the geochemical environment, we collected and analyzed soil from various bedrocks and the grass growing on them. We also analyzed spring and stream waters, including large water supply accumulations, for major chemical elements and examined the serum of healthy adults in the large area of Zlatibor for selenium (Se) and magnesium (Mg). Our studies included villages, small towns, and the town of Uzice. Our results showed a variable Se content in the soil over different bedrocks. In general, soil in this area has a higher Se content than in other regions of Serbia. The Se content of the grass is influenced by bedrock and soil mineralogy, but mostly by soil pH and the date of collection. For example, in late summer, grass contains twice as much Se than in spring. Mg2+HCO3(-)-type waters occur in the ultramafic massif of Zlatibor in a concentration of 44 to 68 mgMg/L. The serum Se values were higher in the Zlatibor area than in other regions of Serbia (62.6 +/- 14.9 microgSe/L; n = 158). The serum Mg content (22.7 +/- 2.2 mg/L; n = 158) was in the uppermost part of the reference range. Taking into account their biological role, the Se and Mg levels in the human population in the Zlatibor area could influence the lower mortality rates of cancer and CVD in this region compared with other regions in Serbia.

Selenium deficiency in Yugoslavia.

Data on selenium (Se) deficiency in Yugoslavia are presented. The results include Se content of soil, cereal crops, and garlic grown in these soils, and human serum and scalp hair from several towns and regions. All data indicate a serious Se deficiency: soil (n = 140), the mean value of 200 +/- 69.6 micrograms/kg Se; wheat, (58) mean = 20.5 +/- 12.4 micrograms/kg; corn, (79) mean = 13.7 +/- 13.6 micrograms/kg; and garlic, (66) mean = 13.7 +/- 17.1 micrograms/kg Se. Analyses of human tissue show a very low Se status of the Yugoslav population: serum, (n = 875) mean = 50.0 +/- 18.0 micrograms/L and scalp hair, (388) mean = 94 +/- 16 micrograms/kg Se. In some regions, Se contents of grain, garlic, and human serum and hair are approaching those in the low-Se belt in China. It is assumed that very low Se status of a human population could be a risk factor in the development of Balkan Endemic Nephropathy (BEN) and in a high incidence of urinary tract tumors (UTT) in endemic areas.

Selenium deficiency in Yugoslavia and possible effects on health.

New data on Se-deficiency in Yugoslavia are presented. The results include Se contents of soils, cereal crops and garlic grown in the investigated soils, and human serum and scalp hair from several towns and regions in this country. All data indicate a serious Se-deficiency. Analyses of human tissues show a very low Se-status of the Yugoslav population. In some regions, Se contents of garlic, grains and human serum and hair are approaching those in the low-selenium zone in China. It is assumed that the very low Se-status of the human population could be a risk factor for the endemic nephropathy and the urinary tract tumours in endemic areas.