Source identification and implications of heavy metals in urban roads for the coastal pollution in a beach town, Busan, Korea

Heavy metals in the sediments of urban roads (RDS), storm drains (SDS), and marine areas (MS) were investigated to assess road pollution in a beach town adjacent to the coast in Busan and identify their relationships with the marine environment. RDS were considerably polluted with Zn, Cu, Cr, and Pb, with mean concentrations of 1090, 178, 171, and 199 mg/kg, respectively. MS were severely contaminated with Zn and Cu, exceeding the effects range median (ERM; Cu = 270, Zn = 410 mg/kg). PCA and HCA identified tire and brake wear in RDS as the major sources of Zn, Pb, Cu, and Cd, and that high levels of Zn, Cu, and Pb in RDS originating from traffic activities contaminated MS through the urban storm drain system. The results suggested that traffic-originated metals in RDS are potential pollutants in coastal environments, and further studies on their fate and management should be conducted.