Chromosomal aberrations induced by cassava industrial effluent using Allium Cepa assay

This study assessed the heavy metal compositions and chromosome aberrations induced by cassava industrial effluent using Allium cepa meristem assay. Effluent collected at the point of discharge from the cassava processing factory located at Lokoja, Kogi State Nigeria was analyzed for quantity of Cadmium  (Cd), Chromium (Cr), Copper (Cu), Manganese (Mn), Iron (Fe), Nickel Ni, Cobalt (Co) and Lead (Pb) using Atomic Absorption Spectrophotometer method. Onion (Allium cepa) roots were allowed to grow in beakers containing different concentrations of cassava industrial effluent (i.e. 25%, 50%, 75% and 100%) and the control for 24 hours. Harvesting of the tips for chromosome observations was carried out between 8:00 to 9:00am West Africa Time. Data pooled under X400 magnification of the light microscope for mitotic phases and chromosome aberrations were analyzed using Analysis of Variance (ANOVA) while means with significant difference across concentrations were separated using Duncan Multiple Range Test (DMRT). The results revealed that only Cadmium (Cd) and Lead (Pb) concentrations in the effluent were higher than the minimum values recommended by World Health Organization. The effluent also produce binucleate cells, variant chromosomes, C-mitosis, vacuolated cells, tripolar anaphase and anaphase bridge which suggests the mutagenic and cytotoxic activities of the industrial effluent. The decrease in the Mitotic Indices (MI) of effluent-treated root cells compared to the control indicates mito-depressive ability of the effluent at every concentration. Regular monitoring of industries for compliance to treatment of effluent before releasing them into the environment is recommended.