ABSTRACT

This study was conducted to assess the human health risk associated with heavy metals in food crops and soils. Heavy metals via the consumption of these food crops were investigated: fruits (Carica papaya, Citrus sineensis, Chrysophyllum african urn), tubers (Dioscorea rotunda/u. Manihot esculenta, Colocasia esculenturn), nuts (Cola acuminate, Cocos nucifrra, Eluc is guineensis) and vegetables (Talinuni triangulare, Vernonia arnygdalina, Tel/aria occideniulis). These samples were collected from an industrialized area — Coca-Cola bottling company in Ninth mile of Enugu state and also from a non- industrialized area in Umudike located at Ikwuano local government area in Abia state. The concentrations of the heavy metals investigated (Mn, Fe, Zn, Cu, Cd, Pb) were determined using an Atomic Absorption Spectroscopy (AAS). The relative abundance of heavy metals across the locations and all samples were in the order Fe>Mn>Zn>Cu>Pb>Cd. The mean concentrations were as follows 2611.47±1.67, 381.80±1.70, 120.12±1.82, 83.20±15.10, 11.06±0.46 and 1.67±0.17 mg/kg dry weight respectively. The results shows that there was statistical significant difference on the concentrations of the six heavy metals investigated at p<O.05 level. The daily intake of the heavy metals from the food samples were below the established oral reference dose for Mn. Ln. Fe and Cd while Pb and Cu from the industrialized area exceeded the oral reference dose. The observed THQ of Pb, Cu, Cd and Zn are generally <1. This observation suggests that consumption of the food crops from the study site may not expose the populace to health risks from intake of individual metals through the food crops. However, THQ values from Mn and Fe were >1 this may be of concern to the exposed population. The estimated average value lot' ingestion cancer slope factor shows that the populace may suffer cancer health risk due to Pb and Cd carcinogenicity. Generally, these food crops may not pose serious health risk to the exposed population.