The impact of anthropogenic factors, particularly hostilities, on water quality and biochemical indicators of fish is an urgent issue of the environmental monitoring. This study assessed the impact of water contamination on levels of cortisol, thyroxine and glucose in blood plasma of two fish species: common roach (Rutilus rutilus) and silver crucian carp (Carassius gibelio). The studies were carried out in the Desna, Danube and Ros rivers, which were subjected to different degree of anthropogenic load as a result of hostilities. It was stated that with deterioration of water quality, the content of cortisol and thyroxine mainly increases, and the glucose content in blood plasma of both fishes decreases, as manifestations of the stress reactions development. Roach was found to be more sensitive biomarker of pollution, whereas silver crucian carp demonstrated higher tolerance. The results obtained indicate significant changes in physiological state of fishes and confirm the feasibility of biochemical parameters as indicators of the ecological state of the aquatic environment.
Potrokhov et al. (Thu,) studied this question.