Evaluation of kidney histopathological alterations in Crucian Carp, Carassius carassius, from a pesticide and PCB-contaminated freshwater ecosystem, using light microscopy and organ index mathematical model

This study aimed to evaluate the potential toxic effects of chronic sublethal pesticides and polychlorinated biphenyl (PCBs) exposure on feral crucian carp, Carassius carassius, using histopathological alterations as an endpoint. Besides, a mathematical model of organ index was used to evaluate the severity of tissue damages. Circulatory disturbances, inflammation, regressive and progressive changes of tubules, glomerulus and interstitial tissue of kidneys were the most frequent damages observed. Organ index calculation revealed moderate occurrence of damage in kidneys of fish compared to the reference site. Findings highlight the effectiveness of organ index as a measuring kidney’s damage severity and health status of fish. The present work is the first study that determines the levels and effects of pesticides and PCBs in water and fish kidneys in Seferani Lake in Albania. The results suggest that the observed changes in kidney structure of C. carassius, could possibly indicate a prolonged chemical stress caused by pesticides and PCBs suggesting continuous monitoring of the lake to protect human consumer’s health.