Analysis of heavy metals in barley dust and health risk assessment in Malt Factory, Ethiopia

Abstract

The recent rapid industrialisation in Ethiopia has become a critical concern from pollution of the environment, including contamination by heavy metals. The purpose of this study was to determine heavy metals in barley dust and evaluate the health risks associated with workers in Gondar Malt Factory, Ethiopia. For this, the concentrations of some potentially toxic heavy metals (Cu, Ni, Cd, Cr, Pb, Zn and Fe) were determined in samples from four different production lines (barley receiving, aspiration, grading, and final product dispatch lines). Prior to metal analysis by flame atomic absorption spectroscopy, a 1 g barley dust was subjected to an optimised wet digestion procedure using 8 mL HNO3, 4 mL HClO4 heated for 4 h at 250°C. The average concentration (mg/kg) of the metals was found to be in the range of 3.3‒4.8 Cu, 4.7‒9 Cd, 9.5‒11.5 Pb, 3063‒3463 Fe, 17.7‒24.7 Ni and 148‒180 Zn. Chromium was below the detection limit of the method in all the samples. The results showed that the barley dust contained significant concentration of the heavy metals. However, the study has found the absence of non-carcinogenic risk, from the analysed heavy metals in the barley dust, through both dermal contact and inhalation routes of exposure. Similarly, no carcinogenic risk was associated with the analysed heavy metals in the barley dust, except for Pb. Hence, proper management control system needs to be implemented to minimise chronic health risks from exposure to Pb.