Assessments on the potential genotoxic effects of fipronil insecticide on Allium cepa somatic cells

Abstract

The potential genotoxic influences of fipronil insecticide were analyzed by studying mitotic index and phases, chromosomal abnormalities, and micronucleus percentage on the somatic cells of Allium cepa L. The roots were treated with 1, 2.5, 5 and 10 ppm of fipronil insecticide within 6, 12 and 24 h. Mitotic index was clearly diminished by fipronil in each treatment group in comparison with control. The percentages of mitotic stages have been significantly affected. Fipronil markedly enhanced the abnormality cell percentage in almost all of the concentrations and treatment times compared to the control. Chromosomal abnormalities were recorded as disturbed prophase, sticky, chromatid bridges, c-mitosis, and laggards. The micronucleus was found at interphase and its frequency was calculated at each concentration and in the control. Generally, micronucleus formation augmented with increasing concentration of fipronil as compared to control. Consequently, the genotoxic potency of fipronil insecticide with different assessments was evaluated by using the somatic chromosomes of A. cepa, and the use of a defined non-toxic dose was suggested.