Agricultural wastes generated from pilled cassava tubers contribute significantly to pollution of the environment. In this study, we investigated the potential genotoxic effects of the effluents obtained from the processing of cassava tubers into three popular Nigerian cassava meals; garri, lafun and akpu using the modified Allium cepa assay. A series of 10 onion bulbs were cultivated in 0.001, 0.01, 0.1, 1.0 and 10% concentrations (effluents, v/v) of each of the test samples (garri, lafun and akpu). At 48 h, root tips from the treated bulbs were processed for cytological studies by the acetocarmine or orcein-orcein squash technique. At 72 h, their cytotoxic effects on the onion root tips showed strong growth retardation in high concentrations of all the effluents with EC50 values of 1.5, 2.5 and 3.5% for garri, lafun and akpu effluents, respectively while total phytotoxic effects was induced by the undiluted effluents. The physico-chemical properties of the effluents revealed the presence of significant amounts of cyanide and heavy metals. Root length inhibition, breakages and malformations were characterized by the presence of crochet hooks and c-tumors at low effluent concentrations (10-1, 10-2 and 10-3%). There was a rapid decrease in mitotic index with increasing effluent concentration. Effluents-induced chromosome aberrations in the root tip cells were statistically significant (p<0.05). The present findings indicate that the substances contained in the cassava effluents may be toxic to living organisms and may pollute the environment.