Health risk assessment of heavy metals in road dusts in urban parks of Beijing, China

摘要

Due to the continuous urbanization and industrialization in many countries of the world,heavy metals are continuously emitted into the terrestrial environment and pose a great threat on human health.A detailed study was conducted to determine the concentrations of six heavy metals (Cr,Ni,Cu,Zn,Cd and Pb) in road dusts in urban parks of Beijing,and assessed the health risk of these metals for local people.The dust samples were collected from 13 different urban parks in Beijing,China.The health risk was assessed using Hazard Quotient (HQ) and Health Index (HI).The results show that the average concentrations of Cr,Ni,Cu,Zn,Cd,Pb in the dust samples are 69.33,25.97,72.13,219.20 0.64 and 201.82 mg/kg,respectively.The concentrations of Cu,Zn,Cd and Pb were much higher than those in the background value of Chinese soil.The assessment of health risk indicated that there were mainly three exposure pathways for people:ingestion,dermal contact and inhalation.The main exposure pathway of heavy metals to both children and adults is ingestion.The values of HQ and HI are lower than the safe level (=1),indicating no health risk exists in present condition.Meanwhile,the HI value for children is higher than that for adults,indicating that children have higher potential health risk than adults in Beijing parks.