Ecological Impact and Human Health Risk Assessment of Pumpkin and Spinach Cultivated Around Non-Mining Axes of Ebonyi State

Abstract

The study evaluated human health risks associated with the consumption of pumpkin and spinach cultivated around non-mining areas of the Asu River Group. Eighteen samples were collected and analyzed for As, Pb, and Cd, obtaining fifty-four results. The samples were washed with deionized water, air-dried and oven dries at 105°C for 48 hours, and analyzed using Varian (USA) Atomic Absorption Spectrophotometer. The concentration of Pb, As, and Cd in the vegetable trend follows; Ebonyi south (ES)<Ebonyi central (EC)<Ebonyi north (EN); EN<ES<EC and ES<EC<EN respectively. The Cd, As, and Pb contents were below WHO/FAO, (2007) and EU, (2006) specific limits. The daily intake of metals (DIM), health risk index (HRI), and targeted health quotient (THQ) were computed. The DIM of Pb, As, and Cd was below their respective oral reference dose (RfD) of 0.004, 0.003, and 0.001mg/kg/day. Pb, As, and Cd HRI values for adults, teenagers, and children are in the following order Adult<Teenagers<Children for all samples across the study area. The Pb abundance follows ES<EN<EC in both pumpkin and spinach, and Cd follows EN<EC<EN and EN<ES<EC for pumpkin and spinach respectively. Arsenic HRI in order of EN<EC<EN and EN< ES<EC for pumpkin and spinach respectively. On average, the HRI of Pb, As, and Cd ranges from 0.00312 to 0.0663, 0.00411 to 0.238, and 0.009 to 0.331 mg/kg/bw/day for the vegetables. The HRI and THQ for adults and teenagers were all <1 for As, and Pb while Cd THQ>1 in pumpkin from ES.