PESTICIDES OF MODERN CLASSES IN THE WATER AND BOTTOM SEDIMENTS OF TAGANROG BAY

Abstract

. The rivers flowing into Taganrog Bay are almost entirely surrounded by agricultural land, where the use of chemical plant protection products is inevitable. This, in turn, leads to the ingress of active ingredients (AI) of pesticides into the water and bottom sediments of the water bodies of fisheries importance. In the water and bottom sediments of Taganrog Bay, the content of 20 active ingredients of the pesticides of modern classes most widely used in agriculture in the region, the half-life of which can exceed six months, has been investigated using high-performance liquid chromatography (HPLC). As stipulated by the State Assignment, the research was being conducted throughout the year in 2014–2016 and in the spring and summer seasons in 2020. As a result of this investigation, such moderately toxic substances as clopyralid, pencycuron and tebuconazole have been identified as the main contributors to the pollution, while in 2014–2016, the main contaminant was low-toxic imidacloprid. In 2020, the total content of pesticide AIs has increased considerably both in terms of concentration and the number of substances found. However, the concentrations of pesticide AIs in the living environment of the hydrobionts in Taganrog Bay turned out to be lower than the established maximum allowable concentrations (MAC) developed for the water bodies of fisheries importance.