The potentials of hospital incinerator bottom ash leachate (HIBAL) to induce cyto-genotoxicity in Allium cepa and reproductive anomalies in the mouse were investigated. The leachate obtained from simulation of the bottom ash was analyzed for some physico-chemical parameters. The A. cepa, mouse sperm morphology and histopathological tests were carried out at concentrations ranging from 1% to 50% of the leachate sample. In A. cepa, HIBAL caused significant (p < 0.05) inhibition of root growth and induction of chromosomal aberrations. In the animal assays, there was 100% mortality at the 50% concentrations. The leachate caused insignificant (p > 0.05) concentration-dependent induction of various types of sperm morphology. There was accumulation of fluid in the seminiferous tubule lumen and necrosis of stem cells in the testes. These effects were believed to be provoked by the somatic and germ cell genotoxins, particularly the heavy metals in the leachate. Our finding is of environmental and public health significance.