Studies of the genotoxicity of technical products of the benzoylcyclohexane-1,3-dione derivative pesticide

Introduction. Currently, a large number of pesticide analogues manufactured past the expiration date of the patent protection of the original active ingredients are imported in the Russian Federation. The toxicological-hygienic examinations based on numerous trials, including mutagenicity (genotoxicity) studies, is necessary to confirm their safety.

Material and methods. The study of the genotoxic activity of three technical products of the pesticide active ingredient, a benzoylcyclohexane-1,3-dione derivative, produced in the various factories was carried out.

Research was performed using the bacterial reverse mutation method (Ames test) and the in vivo mouse bone marrow micronucleus test.

Results. Statistically significant and dose-dependent genotoxic effects of the test samples were observed in the strains of Salmonella typhimurium of TA 97, TA 102, TA 100. However, the increase in the number of revertants in the experiment versus the negative control was less than two in all cases, with the exception of strain TA 97. Weak but biologically significant outcomes were found in TA 97 culture (the increase in the number of revertants in comparison to spontaneous level was ≥ 2. In the micronucleus test only two of the three samples produced a statistically significant increase in the incidence of micronucleated polychromatophilic erythrocytes. One of the samples induced the significant genotoxic effect only at the high dose (2000 mg/kg b.w.), and another one (with the lowest active substance content) at all dose levels. In both cases, a linear dose-effect dependence was found. The cytogenetic effects were low, at the level of the upper limit of the laboratory's historical negative control.

Conclusion. The obtained data indicate that the ability of the tested technical products of the benzoylcyclohexane-1,3-dione derivative to induce the gene and chromosomal damages increases with decreasing concentration of the active ingredient in technical products, probably due to the enhancement of the genotoxic impurity level. Thus, the technical products of analogue pesticides are not always equivalent to the original active substances in terms of their biological activity. That confirms the necessity for toxicological-hygienic testing, in particular genotoxicity assessments of all generic pesticides entering the market.