Current Research Bulletin

Cassava (Manihot esculenta) is a staple crop for peasant farmers in Nigeria and other tropical African countries. Cassava milling engines release heavy metals from dewatering machines, grates, and lubricating grease, contributing to environmental pollution. These metals persist in the soil and accumulate in living organisms. This study analyzed heavy metal contamination near cassava processing mills in Aba, Abia State, Nigeria. Fifteen samples, including cassava wastewater, wastewater-contaminated soil, and pristine soil, were collected from five locations in Aba. Heavy metal presence was determined using Atomic Absorption Spectrophotometer (AAS). Metal concentrations in wastewater followed the order: Fe > Mn > Ni > Cu > Zn > As > Pb > Cd. In contaminated soil, the order was: Fe > Mn > Zn > Cu > Pb > As > Ni > Cd, while in pristine soil, it was: Fe > Zn > Mn > As > Ni > Pb > Cu > Cd. Iron levels were highest in all samples, with manganese, nickel, copper, zinc, arsenic, and lead at lower levels, and cadmium being the least. Heavy metal levels in contaminated soil were significantly higher than in pristine soil, indicating anthropogenic pollution. This accumulation is concerning due to its negative impact on the environment and human health.

Aba, Abia State, Heavy metal, Manihot esculenta, Wastewater

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