Illegal Mining and Armed Banditry in Katsina State, Nigeria: What is their Contribution to the Heavy Metal Pollution of a Popularly Consumed Vegetable?

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. Cabbage leaves sample from Makiya 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 value of the evaluated heavy metal Pb from the sample falls above the Maximum Allowable Concentrations (MAC) of heavy metals in leafy vegetables. The concentrations of the other metals including Fe, Cu, Zn, Ni, Mn and Cd evaluated in the sample were within the permissible values The result of the Target Hazard Quotient (THQ) associated with the evaluated heavy metals exposure through consumption of the sample for adults and children were all below 1. The combined health risks for all the metals in the sample for the adults and children population represented as the HRI were below 1, the result of the Incremental Life Cancer Risk (ILCR) for both the adults and children population shows that all the heavy metals have ILCR that falls within the safety limit for cancer risk. Because of the above permissible Pb concentration in the analysed cabbage leaves sample, it can be deduced that the vegetable is not safe for consumption.