A Histological Examination of the Sublethal Effects of Methyl Parathion on the Liver, Gills and Gonads of Alburnus Tarichi (Güldenstädt, 1814)

Abstract

Pesticides are chemicals used to control a wide variety of animals and plants. Methyl parathion (MP) is an organic phosphorus insecticide used in agriculture against animal organisms that damage the crop. Pesticides can reach water resources in different ways. May affect non-target organisms such as fish to varying degrees. Since fish is a valuable nutrient in human nutrition, its sustainability is very important. For this reason, sublethal effects of MP on Alburnus tarichi, which is economically important for the Lake Van basin, were studied. This study was carried out to determine the pathological effects of MP on the gonad, gill and liver tissues of Alburnus tarichi. Fish weighing 3‒7 g were used in the study. The semi-static test method was applied. Fish were exposed to 4.28 mg L-1 MP. The bioassay was carried out at 17.9 °C for 30 days. At the end of the test, gonad, gill and liver tissues were removed from the dissected fish for pathological evaluations. In the examinations made, cells with eosinophilic and fat accumulation in the liver, local necrosis and enlarged vessels, and yellow colored structures were determined. Thickened primary lamella, folded secondary lamella and epithelial layer separations were observed in the gills. No pathology was found in ovarian cells. Degeneration in the germ cells in the mitotic phase, interstitial tissue containing eosinophilic cell groups, enlarged follicle lumen and bleeding were observed in the testes that were not in the mitotic phase. As a result, MP is a chronic toxic substance according to histological criteria for Alburnus tarichi. MP should be used in agriculture in a controlled and careful way. © (2023). All Rights Reserved.