Assessment of human health risk concerning edible plants contamination with toxic elements around functional and derelict mines

Abstract

Edible plants samples were analysed for non-carcinogenic and carcinogenic human health risks. The elements nickel (Ni), cadmium (Cd), arsenic (As), lead (Pb), chromium (Cr) and mercury (Hg) analysed using atomic absorption spectrophotometer (AAS). The recovery, limit of detection (LOD) and limit of quantification (LOQ) ranged from 75 to 89 %, 0.001–0.003 and 0.003–0.01, respectively. The mean value of Hg (0.34 mg/kg) exceeded the limit of 0.05 mg/kg recommended by World Health Organization (WHO). The estimated daily intake (EDI) of Cd in adults ranged from 7.93 × 10−7 to 1.43 × 10−4 and that of Hg from 0.07 to 1.27 and Cd (0.08 × 10−4) in children. These are below the oral reference doses (RfD). Hazard Quotient (HQ) of Hg in children was 1.92. The elements Hg and As obtained the highest total hazard (THI) index of 2.02 in mango1 and oil palm. Arsenic possessed the highest cancer risk of 4.5 × 10−4 in children and 1.9 × 10−4 in adults. Cancer risk (CR) ranged from low to moderate (10−6-10−4), which is below the limit of 10−3. The total carcinogenic risk (TCR) of the edible plants were above the limit of 10−6. The study identified minimal As and Hg pollution and carcinogenic risks in edible plants.