Health Risk Assessment of Heavy Metals in Vegetable: The Contribution of Illegal Mining and Armed Banditry to Heavy Metal Pollution in Katsina State, Nigeria

Abstract

The health risk to the population from exposure to heavy metals in an area that have witnessed a surge in illegal mining activities, cattle rustling and banditry were evaluated in the current study. Moringa leaves sample from Jabiyawa village, Jibia local Government area, Katsina State, Nigeria was evaluated for the presence of heavy metals using Atomic Absorption Spectrophotometry. The health risks of the evaluated heavy metals in the sample to the population were assessed using the Target Hazard Quotient (THQ) and Health Risk Index (HRI)) to assess the possible non-carcinogenic effect and the Incremental Lifetime Cancer Risk (ILCR) for the cancer risks. The result of the mean concentration values of the evaluated heavy metals Fe, Cu and Pb from the sample falls above the Maximum Allowable Concentrations (MAC) of heavy metals in leafy vegetables. The concentrations of the other metals including Zn, Ni, Mn and Cd evaluated in the sample were within the permissible values The results of the Target Hazard Quotient (THQ) associated with the evaluated heavy metals exposure through consumption of the sample for adults and children were below 1, with exception of the THQ for the heavy metal Cu in the children population that was above 1. The combined health risks for all the metals in the sample for the adults and children population represented as the HRI were above 1. The result of the Incremental Life Cancer Risk (ILCR) for both the adults and children population shows that the heavy metal Ni is beyond the threshold of the safety limit for cancer risk. There is a health risk concern from consumption of the sample as the vegetable may contribute to the disease burden of the population.