Evaluation of Health Risks in Cairo due to Deposited Dust Contaminated with Heavy Metals

Abstract

Heavy metals in deposited dust at five urban districts in Cairo, Egypt, during 2015 were studied. Risk assessment modeling was applied to evaluate health risks of these metals for adults and children. The results show that contamination levels of metals were in the order of Ni > Cr > Ba > Cu > Zn > Cd > Pb > Co, suggesting a very high degree of contamination of deposited dust in Cairo.The daily doses exposure was ranked in the order Dingestion > Ddermal contact > Dinhalation for children and adults (carcinogenic risk), while in the case of adult noncarcinogenic risk the ranking order was Ddermal contact > Dinhalation > Dingestion at all sampling sites. The highest contribution to hazard indices in children was from hazard quotients (HQing), compared with low or negligible contribution of HQing in the case of adults. The carcinogenic risk was assessed for adults and children via three exposure routes with order of Ringestion > Rdermal contact > Rinhalation. Finally, cancer risk values for heavy metals in Cairo are within the safe levels.