Cytogenotoxic effects of electronic waste leachate in Allium cepa

Information on the potentials of electronic waste (e-waste) leachate to induce genotoxicity in eukaryotic cells is scarce. In this study, we investigated the potential of raw and simulated e-waste leachates to induce cytotoxicity and DNA damage in Allium cepa. Roots of onion bulbs were grown in five concentrations: 1, 5, 10, 25 and 50% (v/v; leachate/tap water) of each of the leachate sample, tap water (negative control) and 0.25 ppm lead nitrate (positive control). Cytogenetic and root length inhibition analyses were evaluated at 48 and 72 hours respectively. There was concentration-dependent significant (p < 0.05) inhibition of root growth and cell proliferation compared to the negative control. The leachates also induced morphological modifications of the roots and cytological aberrations such as anaphase bridge, sticky chromosomes and binucleate cells. Fe, Cd, Mn, Cu, Ni, Cr As, Zn and Pb analysed in the samples were believed to play significant role in the observed cytogenotoxicity in A. cepa. These observations indicate that e-waste leachate contained substances capable of inducing cytotoxicity and somatic mutations in A. cepa. This is of environmental and public health importance in Nigeria and other developing nations whose populations are at risk of e-waste exposure.