Risk Assessment of Heavy Metals in Food Crops at Abandoned Lead-Zinc Mining Site at Tse-Faga, Logo, Lga, Benue State, Nigeria

摘要

Hundreds of children died in 2010 due to suspected lead poisoning from mining sources in Zamfara State among epidemiological concerns. Evaluating ecological and human health risks of heavy metals levels in sampled food crops harvested near two abandoned Lead-Zinc mining sites at Logo Benue State is crucial. Abelmoschus esculentus , Carica papaya , Manihot esculenta , and Zea mays were sampled, prepared, and analyzed for four heavy metals using the Atomic Absorption Spectrophotometric method. The mean data from the analysis of variance was subjected to ecological and health risk models. Pb means value ranged from Carica papaya Peel 0.46 ± 0.011 mg/kg to 1.30 ± 0.01 mg/kg in Zea mays seed. Zn was highest in Carica papaya flesh 0.50 ± 0.01 mg/kg, and lowest in Manihot esculenta peels and its flesh 0.12 ± 0.000 mg/kg. Hg and Cd were below detectable levels. Zea mays seeds (1.001) had the highest Pd bioaccumulation factor. BAF of zinc and ecological indices were <1. Daily Intake of Metals were all <1, however, Hazard Quotient (HQ) of Pb was ≥1 in Manihot esculenta flesh 1.143 and Zea mays at 1714. Cancer Risks were within permissible range (10~(-4) - 10~(-6)). Health Risk result indicates communities around the mining area may be at risk of lead poisoning therefore due to high contamination of samples, routine checks on heavy metals especially lead is recommended to prevent excessive bioaccumulation in the body.