For children, HQs and HIs of six metals are almost all lower than the safe level (=1), indicating no
risks from these metals. On the whole, HI value decreased in the order of Cr >Pb >Cu>Ni>Zn>Cd. Pb
and Cr exhibited higher values close to safe level, while Zn and Cd are lowest. However, there are several
places where the concentration and values of Pb are much higher than the safe level for some reason. So
Pb should be paid more attention for the high HI value (HI=0.741) as well. Pb should be mostly
concerned regarding the potential occurrence of health impacts [33]. Pb in the urban environment had a
widespread influence on children health, and a main source of blood Pb for children is ingestion of
contaminated dust or soils[34]. Shenzhen, a densely populated city in China, has detected excessive the
blood Pb level in two-thirds of the city’s children, reflecting what many believe is a problem throughout
China’s industrialized cities[35]. At the same time, the Cr also should be focus on. Although the
concentration of Cr is almost equal to the background values, the potential health risk is quite high for
children(HI=0.805), the potential effects in the road dust should arouse more concern.