The Role of Trace Elements in the Adaptation of Fish Metabolism under Reduced Pollution: A Case Study of the Subarctic Lake Imandra

The mechanisms of fish adaptation to survival in the historically contaminated Lake Imandra were studied. The role of trace elements in the protective functions of the organism and their importance in the re-adaptation of organisms to improving the habitat was established. The lake whitefish ( Coregonus lavaretus L.) unable to migrate for large distance was chosen as the object of research. The indices of red blood as an indicator of fish homeostasis, as well as the role of white blood cells in the activation of the immune system were examined. The causes of the occurrence of histopathologies of organs and tissues are explained. Data on the accumulation of trace elements in the body of fish from this lake are presented. The principal difference in the bioaccumulation of elements is the intense metabolism of Se. An elevated S to Se ratio indicates a high antioxidant status of fish from the historically contaminated part of the lake, while an increased accumulation of Fe, Cu, and Se can serve as a marker of liver pathologies, and Zn and Co, of kidney pathologies.