Assessment of the Toxicity Potentials of Spent Laptop Battery Wastes on Essential Soil Microbes and Plant Bioindicators

Aims: The study was undertaken to assess the toxicity potentials of spent laptop battery wastes on essential soil microbes and plant bio-indicators. Study Design: Five treatments and the controls designs were set up in triplicates and incubated at 25 ± 2°C for 21 days. The five treatments and controls set ups were designated as 6.25%, 12.5%, 25%, 50%, 100% and CTRL. Place and Duration of Study: Department of Microbiology, Chukwuemeka Odumegwu Ojukwu University (COOU), Uli Anambra State, Nigeria during May, 2019 - July, 2019. Methodology: The microbial growth inhibition was analysed using standard method of spread plate technique while growth indices and percentage seedling emergence were adopted for the seed growth inhibition. Results: The result revealed that fungal population was the most sensitive followed by bacterial population and then actinomycetes population in terms of toxic responses to the spent laptop battery samples soil contamination. The order of toxicity of the spent battery samples on the growth indices and percentage seedling emergence of P. vulgaris and S. bicolor were: Product B-bean (-18.89%) > Product A-sorghum (-32.22%) > Product A-bean (- 38.63%) > Product B- sorghum (- 45.77%) revealing that both P. vulgaris and S. bicolor are very good bio-monitoring models for spent product A and B battery pollution assessment. Conclusion: Thus, strict and stringent measures on release of these electronic wastes in the environment are recommended.