Authors: Yukun Ma, Prasanna Egodawatta, James McGree and An Liu
Abstract: In recent years, stormwater reuse has become increasingly popular in the urban areas around the world to overcome water shortages. However, the presence of heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) in urban stormwater are a great concern due to their toxic effects on human health. In this context, assessment of risk to human health posed by HMs and PAHs in urban stormwater is essential. This paper discusses the outcomes from a study which assessed the risk from HMs and PAHs in stormwater and the influence of traffic and land use characteristics on the risk. Build-up data were collected from twenty study road sites in Gold Coast, Australia. The study found that Cr, Pb and Mn contribute the most to the risk from a HM mixture even though they are at low concentration in urban stormwater. In terms of PAH mixture in stormwater, the risk is primarily influenced by the heavy PAHs with 5 to 6 benzene rings. Both traffic and land use have influence on the risk and high traffic volume and high intensity of industrial land use contribute to high risk from HMs and PAHs.
Keywords: heavy metals; polycyclic aromatic hydrocarbons; stormwater quality; risk assessment