Bioaccummulation and health risk assessment of some potentially toxic elements in crops from farms round granite quarry sites in ibadan southwestern nigeria

Abstract

Potentially toxic elements (PTEs) in food crops have significant apprehension in the environment because of their impending human health risks. This study thus assessed PTEs concentrations in soils and crops from farmlands around quarry sites, quantifies their level of uptake by the crops and their potential health risks to human. Collection of Soil and crop (Dioscorea alata, Colocasia esculenta and Manihot esculenta ) samples were done and analysed for Fe, Mn, Pb, Zn, Cu, Cr, Co, Ni and Cd using suitable instrumentation methods Data were evaluated using accumulation factor (AF), calculated daily intakes (CDI), target hazard quotent (THQ) and hazard index (HI). Farmlands soils that are closer to studied sites had higher PTEs concentrations than those that are farther away. Mean PTEs concentrations in the crops were in the order of Dioscorea alata > Colocasia esculenta > Manihot esculenta. Mean values of AF are less than one indicating low potential PTEs accumulation in the crops. The mean CDI in mg/kg/day of PTEs in crops for children and adults were 0.0001 -0.060 while THQ values are in order Pb> Mn>Cu> Cd>Ni> Co>Fe >Zn>Cr. Hazard index (HI) is greater than one in all the crops from the farmlands closer to quarry sites, indicating risk upon consumption. Thus, necessary remediation methods should be taken to reduce the effect of these PTEs on the environment.