Long-Term Dynamics of Heavy Metal Concentrations in the Food and Liver of Shrews (g. Sorex) during High and Reduced Emissions Periods from the Copper Smelter

Abstract: The long-term changes in the contents of heavy metals (Cu, Zn, Cd, Рb) in the food and liver of four shrew species of the g. Sorex, in the vicinity of the the Middle Ural Copper Smelter (MUCS) during periods of its high (1990–1997), reduced (1998–2009), and almost ceased (2010–2019) emissions. The minimum concentrations of all elements in the animal organism were noted in unpolluted areas (background zone), the maximum concentrations of Cu, Zn, and Cd were in the immediate vicinity of the plant (impact zone), Cd—at moderate pollution (buffer zone). The species specificity of the accumulation of the considered elements in the liver was determined by the composition of diets and was expressed in increased accumulation of Cu and Cd in the liver of S. araneus and increased accumulation of Pb in the liver of S. caecutiens. A multiple reduction in industrial emissions did not lead to an equivalent decrease in the content of heavy metals (HMs) either in the feed or in the body of shrews. Over 30 years, directed changes in HM concentrations in the liver were noted only in S. caecutiens: in the impact zone (1–3 km from the plant), the content of Zn did not change, the concentrations of Cd and Pb decreased by 1.2–1.5 times, while the concentration of Cu, on the contrary, increased by 1.5 times. In the buffer zone (4–10 km) Cu, Zn, and Pb concentrations remain unchanged, while the concentrations of Cd decreased by 1.5 times; in the background area (20–34 km), the content of essential elements (Cu, Zn) was maintained at the same level, while the concentration of toxic elements (Cd and Pb) decreased by 4–5 times.