Assessment of the potential environmental and ecological risks associated with traffic induced heavy metal contamination in country parks of Hong Kong

Abstract

Hong Kong is a densely populated area with a limited area, so most country parks are adjacent to busy traffic roads and town activities. The soil in country parks may be contaminated by heavy metals emitted by traffic activities. During the holidays, most people go to country parks to play. It is very important to assess the potential risks of residents, especially children. So far, data on pollution in Hong Kong’s country parks is very limited. The heavy metals arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), silver (Ag) and zinc (Zn) were collected in the Kam Shan (KS), Plover Cove (PC), Sai Kung West (SK) and Lion Rock (LR) country parks. The mean Zn concentration in KS Country Park was more than three times higher than the background concentration in Dutch soil standard, while Cu and Pb were more than 1.6 times higher. The average pollution index (PIave) of KS Country Parks was classified as high, and the potential ecological risk index (RI) was classified as moderate. Country parks should pay special attention to heavy metal pollution in order to continue further research and remedial measures.