Abstract:
Abstract: Heavy metals could lead to adverse health risks for multiple target organs of humans, and their interactions may affect the cumulative effects of heavy metals. However, the traditional health risk assessment models did not take the influences of these two factors into account, and failed to reflect the accurate risk of heavy metals to the human body. In order to evaluate the non-carcinogenic health risk of the children exposed to heavy metals from a typical agricultural land in Southern China, levels of As, Cd, Cr, Cu, Pb, Ni, Zn and Hg in soil were detected and their pollution degrees were evaluated by single factor pollution index method (Pi) and Nemerow comprehensive pollution index method (Pc). In this study, the bioavailability of heavy metals and the BINWOE method were employed to optimize the non-carcinogenic health risk models. The results showed that the non-carcinogenic health risk index (HI
HRA) of every single metal was less than 1, and thus their non-carcinogenic health risks were all at acceptable levels. However, the superimposed health risk index of heavy metals (HI
HRA) in the 95th quartile was greater than 1, indicating that the non-carcinogenic health risk exist of combined pollution form the multiple heavy metals. BINWOE method was used to assess the composite non-carcinogenic health risk of four heavy metals (As, Cd, Cr, Pb). The total non-carcinogenic health risk index (HI
WOE) of the four metals to target organs was 1.8143, which was 1.35 times of the traditional HI
HRA (1.3440). Furthermore, the non-carcinogenic health risk was 1.2348 by modifications of heavy metal bioavailability, which was still at an unacceptable level. Therefore, our results emphasize the considering the target organs of each heavy metal as well as their interaction in the target organs for assessing the non-carcinogenic health risk of multiple heavy metals.