Systemic assessment of pesticide genotoxicity

Изучена генотоксичность более 200 технических продуктов (ТП) пестицидов. Разработан алгоритм оценки эквивалентности ТП оригинальным действующим веществам (ДВ) по критерию «мутагенность». Обоснована необходимость изучения генотоксической активности комбинаций ДВ пестицидов. Установлены ограничения тестов на генотоксичность, обусловленные токсичностью пестицидов разных химических классов. Выявлена зависимость ингибирующего эритропоэз действия триазоловых пестицидов от структуры ДВ. Изучено влияние и предложен общий механизм действия карбендазима на процессы кариокинеза, экструзии ядер и цитокинеза в эритроидных клетках костного мозга млекопитающих. Разработаны критерии экспертной оценки мутагенности пестицидов. The genotoxicity of more than 200 technical grade active ingredients (TGAI) of pesticides has been studied. An algorithm for evaluating the equivalence of TGAIs to the original active ingredients upon the criterion of “mutagenicity” has been developed. The necessity of studying the genotoxic activity of the combinations of pesticide active ingredients was substantiated. Limitations of the genotoxicity tests due to toxicity of pesticides of different chemical classes have been established. The dependence of the erythropoiesis-inhibiting action of triazole pesticides on the structure of the active ingredient was revealed. The effects and the general mechanism of the carbendazim action on the processes of karyokinesis, extrusion of nuclei and cytokinesis in mammalian bone marrow erythroid cells were studied. The criteria for expert evaluation of pesticide mutagenicity have been developed.

Evaluation of the mutagenic potential of propoxur and methyl parathion using polytene chromosomes of Anopheles stephensi

The mutagenicity of two pesticides, propoxur and methyl parathion was evaluated by using polytene chromosomes of Anopheles stephensi. The results were based on the frequency of various structural aberrations encountered in the polytene chromosomes of the larvae treated with LC20 of propoxur and methyl parathion separately. Propoxur induced a total of 67 aberrations as against 15 in the controls while methyl parathion induced 53 aberrations as against 13 in the controls. These aberrations were dominated by inversions, translocations, deletions, ectopic pairing, asynapses, breaks, fusions and induced puffing. The frequency of propoxur induced aberrations was highest in chromosome 3R followed by 2R, 3L, 2L and X-chromosome. Methyl parathion induced highest number of aberrations in 2R followed by 2L, 3R, 3L and X-chromosomes. This study suggests that larval polytene chromosomes are sensitive indicators of pesticide genotoxicity in which both propoxur and methyl parathion are significantly chromotoxic for the genome of a mosquito taken as an experimental insect.