Cytotoxic and genotoxic effects of 4-methylimidazole on Allium cepa root tips

4-Methylimidazole (4-MeI or 4-MEI) is widely used chemical as cleaning and agricultural chemical, drugs, rubber, dyes and pigments. It is also formed in manufacturing process of class III or IV caramel. In this study, Allium cepa root tips were used for cytogenotoxic effects of 4-MeI by using Allium anatelophase and comet assays. Changes in mitotic index (M), mitotic phase frequencies, chromosome aberrations (CAs) and DNA damage were evaluated after Allium bulbs exposed to three different concentrations (25, 50 and 100 ppm) of 4-MeI at four different time intervals (24, 48, 72 and 96 h) for comparison with a negative (distilled water) and positive control (Methyl methane sulfonate, WS-10 ppm). 4-MeI was found cytotoxic by reducing root growth and MI and was also found genotoxic by increasing CAs and DNA damage. Additional molecular toxicological studies are necessary to verify the cyto-genotoxicity of 4-MeI on plants.