Michael A. Nwachukwu

Assessment of heavy metal pollution in soil and their implications within and around mechanic villages

Analysis of nine composite soil samples, each made of three replicate core samples and their respective background samples collected from Okigwe, Nekede and Orji automobile mechanic villages were conducted. Metal concentrations (mg/kg) above the background levels in the top 100 cm soil profile ranges as follows: 748-70,606 (± 10114.3) for iron; 99-1090 +- 251.3 for lead; 186-600 ± 180 for manganese; 102–1001± 201.9 for copper; 8–23 ± 12.9 for cadmium; 4–27 ± 6.0 for chromium; and 3–10 ± 2.2 for nickel. The order of abundance is: iron > lead > manganese > copper> cadmium > chromium > nickel, with Okigwe > Nekede > Orji. Pollution indexes show that the metals have similar pollution trends in the three layers (L1–L3), with L1 (0–10 cm) > L2 (10–20 cm) > L3 (90–100 cm) in Okigwe, L3 >L1>L2 in Nekede, and L3 >L2 >L1 in Orji. In effect, the shaly Okigwe soil is more polluted in the top layer while the sandy Nekede and Orji are more polluted in the lower layers. Despite this order, metal bioavailability may be less in the Okigwe soil due to its high clay-silt content (47 %–64 %). Pollution factor for Okigwe is 0.8, Nekede is 0.7 and Orji is 0.5. Nekede is under severe to excessive pollution while Orji and Okigwe are under moderate to excessive pollution, with weathered depths 7.4m at Orji and Nekede and 4m at Okigwe as most implicated in the pollution process. Above provides the bases for introducing the innovative concepts of environmentally friendly mechanic village.

Review and assessment of mechanic village potentials for small scale used engine oil recycling business

Mechanic village should be adapted in developing countries rather than the city-wide auto mechanic workshop practice. This is suggested because developing countries are yet to enforce environmentally friendly automobile workshops and mechanic practice. If all automobile repair works in different cities are confined to mechanic villages, collection, preservation, recycling and reuse of spent oil will become effective. The goal is to stop the habit of disposing spent automobile oil on the ground, which results in excessive trace metal pollution of topsoil and insecurity of food products in the affected areas. Beside environmental quality, business and employment opportunities will improve. Small-scale refining or reprocessing of used oil in mechanic villages is lucrative and recycling plants are affordable and available. Cost benefit analysis indicate strong environmental benefits and annual turnover in excess of

Global capacity, potentials and trends of solid waste research and management

2,234,375.00. Key words : Changed oil, reprocessing, re-refining, cost benefit analysis, auto repair, Nigeria.

Integrated study for automobile wastes management and environmentally friendly mechanic villages in the Imo River basin, Nigeria

In this study, United States, China, India, United Kingdom, Nigeria, Egypt, Brazil, Italy, Germany, Taiwan, Australia, Canada and Mexico were selected to represent the global community. This enabled an overview of solid waste management worldwide and between developed and developing countries. These are countries that feature most in the International Conference on Solid Waste Technology and Management (ICSW) over the past 20 years. A total of 1452 articles directly on solid waste management and technology were reviewed and credited to their original country of research. Results show significant solid waste research potentials globally, with the United States leading by 373 articles, followed by India with 230 articles. The rest of the countries are ranked in the order of: UK > Taiwan > Brazil > Nigeria > Italy > Japan > China > Canada > Germany >Mexico > Egypt > Australia. Global capacity in solid waste management options is in the order of: Waste characterisation-management > waste biotech/composting > waste to landfill > waste recovery/reduction > waste in construction > waste recycling > waste treatment–reuse–storage > waste to energy > waste dumping > waste education/public participation/policy. It is observed that the solid waste research potential is not a measure of solid waste management capacity. The results show more significant research impacts on solid waste management in developed countries than in developing countries where economy, technology and society factors are not strong. This article is targeted to motivate similar study in each country, using solid waste research articles from other streamed databases to measure research impacts on solid waste management.