Heavy metal bioaccumulation in Telfairia occidentalis cultivated in cassava mill effluent polluted and unpolluted soils in Aba Nigeria

Heavy metals bioaccumulation in fluted pumpkin ( Telfairia occidentalis ) cultivated in cassava effluent polluted and unpolluted soils was investigated using soil samples collected from five cassava processing sites in Aba, Abia State, Nigeria. Ten experimental units were established using bowls (21 cm diameter) filled with polluted and unpolluted soils. Plants grown in polluted soil were irrigated with cassava effluent, while control plants received water. Growth parameters, including germination time, shoot length, leaf number and yield, were monitored. Concentrations of Fe, As, Pb, Cd, Cu, Zn and Ni in leaves, shoots and fruits were determined using Atomic Absorption Spectrophotometry (AAS). Fluted pumpkins grown in unpolluted soil germinated earlier and exhibited significantly higher shoot length, leaf number and yield compared to those grown in polluted soil. Heavy metal concentrations were consistently higher in plants cultivated in effluent-polluted soil; however, measured values remained within current FAO/WHO permissible limits for vegetables. Given the potential toxicity and persistence of heavy metals in edible plants, continuous monitoring of vegetables cultivated in effluent-impacted soils is therefore recommended to safeguard food quality and public health.