Geographic variation of environmental, food, and human hair selenium content in an industrial region of Russia.

The objective of the present study was investigation of the selenium (Se) levels in environmental samples, main consumed food products, as well as human hair in the areas of the Orenburg region. Se levels in the environmental objects (water, soil, wheat), frequently consumed food products (wheat bread, ryebread, beef, pork, chicken, milk, cottage cheese), as well as human hair samples in the western (n = 210), central (n = 195), and eastern (n = 120) areas were assessed using inductively-coupled plasma mass-spectrometry and atomic absorption spectrometry (soil). The obtained data demonstrate that water (87% and 89%), soil (41% and 48%), and wheat (11% and 11%) Se levels Central and Eastern areas were significantly higher than those in the Western area. The level of Se in foods was found to be the highest in the Eastern (wheat bread and beef), Central and Eastern (ryebread and pork), or Central (milk and cottage cheese) areas of the Orenburg region. Hair Se content (0.298 (0.233-0.591) µg/g) as well as dietary Se intake (84.3 (73.7-95.8) µg/day) did not differ significantly between the studied areas. At the same time, regression analysis demonstrated that Se intake with wheat bread (ß = 0.634; p = 0.042) was the strongest predictor of hair Se. The revealed associations between environmental and food Se content and Se status of the population underline the necessity of continuous monitoring of Se intake and exposure in order to prevent potential health effects associated with both deficiency and overload.

Zinc, copper, cadmium, and lead levels in cattle tissues in relation to different metal levels in ground water and soil.

The objective of the present study was to investigate the interaction between environmental (water and soil) levels of zinc, copper, cadmium, and lead levels, as well as their content in Hereford beef cattle tissues in five districts (D1-western area, D2 and D3-central area, D4 and D5-eastern area) of the Orenburg region. Soil metal levels were assessed using atomic emission spectrometry, whereas water and tissue (liver, kidney, muscle, heart) metal content was studied using inductively coupled plasma-mass spectrometry. The obtained data demonstrate that the highest levels Zn in soil and water (p < 0.001), as well as cattle muscle, liver, and kidney (p < 0.05) were observed in D4 and D5 (eastern area), exceeding the maximum permissible concentration levels (MPCL) for drinking water and muscle for all regions. Similar associations were found for Cu levels. The highest soil and water Cd and Pb content were observed in D2 (central area) and D5 (eastern area), respectively. At the same time, cattle tissue Cd and Pb content did not correspond to the respective environmental levels. Correlation analysis demonstrated that water and soil Zn and Cu content directly correlated with muscle, liver, and kidney, but not heart metal content. At the same time, water Cd levels were negatively interrelated with muscle cadmium content but correlated directly with hepatic metal content. Both water and soil Pb levels positively correlated with renal metal levels in cattle. In turn, soil lead content was inversely associated with muscle metal levels. Regression analysis also demonstrated a significant association between environmental and tissue levels of Zn and Cu. The models adjusted for all studied elements demonstrated a significant effect of metal interaction on tissue metal levels. Hypothetically, excessive environmental Zn, and possibly Cu, levels may affect the uptake of heavy metals including Cd and Pb from the environment.

Copper and zinc levels in soil, water, wheat, and hair of inhabitants of three areas of the Orenburg region, Russia.

The objective of the present study was to assess the level of zinc and copper in soil, water, wheat and hair of inhabitants of the western, central, and eastern areas of the Orenburg region. A total of 525 water, soil, and wheat samples, as well as 420 hair samples were assessed using atomic absorption spectrometry (water, soil, wheat) and inductively-coupled plasma mass spectrometry (hair). The highest levels of Zn and Cu in water (4.9(4.2-5.1) and 1.0(0.9-1.1) mg/l), soil (23.8(20.7-27.0) and 2.6(1.9-3.1) mg/kg), and wheat (24.7(20.5-31.0) and 4.8(4.2-5.5) mg/kg) were observed in the eastern area (p < 0.001). Hair zinc levels in inhabitants of the western (184(165-198) µg/g) and eastern (224(211-253) µg/g) areas of the region exceeded the respective values from the central area by 32% and 61% (p < 0.001). In turn, hair Cu levels in the central (16.4(14.3-17.8) µg/g) and eastern (17.9(16.4-19.0) µg/g) areas exceeded the values from the western area by 10% and 20%, respectively. Correlation analysis demonstrated that hair Zn levels were positively correlated with water and soil content, whereas wheat Zn levels were associated with soil and water content. For copper significant direct correlation was observed only between soil and water Cu content. In multiple regression models, only water zinc level was significantly associated with hair Zn content, although the general model accounted for 55% of variability of hair Zn content. Higher zinc and copper exposure in the eastern area is presumably associated with higher activity of metal-processing industry.