Toxicological characteristics of active ingredient of chlorosulfuron

Introduction. Herbicides have been one of the most effective weed control agents for many decades. They account for more than half of all registered pesticides. In the modern list of herbicides, more than a quarter of all active substances are compounds belonging to the class of sulfonylurea derivatives. Taking into account the specific aspects of the use of pesticides, the requirements for their toxicological and hygienic assessment are increasing every year. Among the promising drugs for the control of annual and some perennial weeds in the cultivation of grain crops, new combined products containing chlorosulfuron are being identified.Aim of the study. To establish the degree of damaging effect with prolonged administration, under the chronic action of drugs based on chlorsulfuron on the body.Materials and methods. In the acute experiment, outbred sexually mature white male rats weighing 220-240 g were used. Each experimental group consisted of twenty animals (10 to determine hematological and biochemical indices and 10 to determine physiological indices). The statistical group included 6 animals. Chlorsulfuron was administered with a metal probe in a 30% solution into the stomach. Doses of 0.5, 5.0, 25, and 50 mg/kg b.w. The toxic effect was judged by changes in integral, hematological, biochemical and physiological indices. A morphofunctional assessment of the long-term effects of chlorsulfuron on the body in warm-blooded animals was carried out. At the end of chronic exposure to chlorsulfuron, 13 organs of rats were collected during necropsy, histological preparations were prepared, and morphological, morphometric, and stereometric analysis of micropreparations was carried out.Limitations. When choosing toxicometric parameters for chlorsulfuronic acid, the intragroup number of rats is 6–8 individuals, depending on the tasks being solved, which is a sufficient reference sample.Conclusion. In a chronic 12-month experiment on conventional white male rats, at all times of the study on animals of the experimental groups that received a.i. chlorsulfuron in doses of 0.5 and 5 mg/kg b.w. Five times a week, no statistically significant changes were detected for all studied causes, hematological and biochemical indices. Statistically significant changes in the studied parameters detected in animals of the experimental groups receiving chlorsulfuron in doses of 25 and 50 mg/kg b.w.Compliance with ethical standards. Study approved of the Ethics Committee of the Federal Research Center of Hygiene named after F.F. Erisman (Protocol of the Ethics Commission No. 01/22 dated 27.20.2022). The study was conducted in accordance with the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS N 123), Directive of the European Parliament and of the Council of the European Union 2010/63/EC of 22.09.2010 on the protection of animals used for scientific purposes.Contribution: Bagreev A.Y. – design of the study, collection and processing of material, writing the text; Rakitskiy V.N. — research concept and design, editing; Bagreeva D.I. – processing of material, writing the text; Vostrikova M.V. — collection and processing of material. All co-authors – approval of the final version of the article, responsibility for the integrity of all parts of the article.Conflict of interest. The authors declare no conflict of interest.Funding. The study had no sponsorship.Received: February 18, 2025 / Revised: March 14 , 2025 / Accepted: March 26, 2025 / Published: June 27, 2025

toxicological studies, chlorsulfuron, sulfonylurea derivatives