Hazard assessment and cytogenotoxic effect of different concentrations of mercury chloride sterilant using the Allium cepa assay

Abstract

The Allium cepa assay represents a crucial in vivo model for evaluating the cytotoxicity and genotoxicity of substances. This study investigated the cytogenotoxicity of mercury chloride (HgCl2), a laboratory disinfectant and catalyst, using the Allium cepa assay. Mitotic slides were prepared from onion root tip cells grown on media supplemented with different concentrations of HgCl2 (0%, 0.2%, 0.4%, 0.6%, 0.8%, and 1.0%). The slides were observed to evaluate cytogenotoxicity based on the assessment of the mitotic index, mitotic inhibition, clastogenic effect, and root length. The results showed that the concentrations used are harmful to the cell, leading to adverse impacts on the mitotic index, mitotic inhibition, root growth, and chromosome structure. Different chromosomal aberrations, such as bridge formation, fragmentation fragments, wandering chromosomes, stickiness, binucleate cells, and micronucleus formation, were detected depending on the concentration. Although lower concentrations (0.2–0.4%) had fewer effects on the cells, they still had a significant cytogenotoxic effect (p < 0.05) compared to that of the control (0.0%). The higher the concentration, the greater the effects on clastogenic changes. The abnormalities in both mitotic spread and root growth indicate that mercury chloride is cytotoxic even at low concentrations and can cause mito-depressive effects at higher concentrations. The results of this investigation can be used as a guide to guarantee sufficient safety precautions for people and organs during the regular use of HgCl2.