Platinum Group Elements in Road Dust and Vegetation from Some European and National Roads with Intensive Car Traffic in Romania

The paper presents a monitoring study of the platinum group metals concentrations in 17 samples of road
dust and vegetation from areas with heavy car traffic on several European and national roads in eastern
Romania. The Ir, Pd, Pt, Rh, Ru concentrations were determined by the ICP-MS technique, the reported
values being below the method’s limit of determination for Ir, Pt and Ru both in soil and vegetation. As
regards the Pd content, it showed a maximum of 794µg / kg dry matter in Focsani area (DN2), an area
where, according to national data published by National Road Infrastructure Management Company, the
traffic average is 16,000 vehicles / 24 h. Approximately 50% of the collected vegetation samples showed a
Pd transfer factor from the solid part to the vegetation higher than 0.5, thus indicating the existence of Pd
toxic compounds bioavailable for vegetation. The highest concentrations of Rh in soil were recorded on a
high traffic section on the E85, in Ramnicu Sarat area, where the traffic interval ranges from 8,001 to 16,000
vehicles / 24 h