Industrial wastes play a major role in the environmental pollutants at least inmajor cities. The objective of the present work was to study the cytotoxic effects of common industrial effluent from PETL, Hyderabad on Allium sativum. As these effluents inhibited the growth of the roots which may be due to the inhibition of the mitotic cell divisions taking place in the root tips, the present investigation was focused to study the cytotoxicity in the root tip cells of Allium sativum.Mitosis division frequency, chromosomal aberrations, micronuclei formation and mitotic index were also considered for evaluation of cytotoxicity. The results showed a clear decline in the mitotic index with the increase in effluent concentration and the duration of treatment. The results also demonstrated othermitotic abnormalities like change in nuclear morphology, nuclear death, perforation, formation of micronuclei, fragmentation of chromosomes, bridge formations, nuclear bursting, and polyploidy.