Abstract: The genotoxic effects of refined petroleum products (Petrol, Kerosene) and locally made soft drink (Zobo) were assessed with the Allium test. The roots were treated with 10, 25 and 50% of these chemicals for 1, 3 and 6 h. These substances exerted depressive effects on mitosis, including reduced mitotic indices and accumulation of mitotic phases. Chromosomal aberrations which include anaphase bridges were observed in petrol and zobo, laggards and vagrant chromosomes observed in zobo while sticky chromosomes were observed in petrol, kerosene and zobo. C-metaphases were observed in kerosene and zobo whereas binucleate cells were observed in petrol and kerosene. Micronuclei were observed in zobo and petrol while ghost cells were observed in root tips treated with the various concentrations of the zobo. These chromosomal aberrations occurred at various duration of treatment time. This suggests that these chemicals are clastogens depending on the exposure time. Therefore, minimal consumption, contact and reduction in the duration of exposure is advised.