The aim of this study is to test two plant species, the common dandelion Taraxacum officinale and moss Pleurozium schreberi, as bio monitors of trace metal pollution emitted by motor vehicles. The samples of the moss Pleurozium schreberi (green segments) and the common dandelion Taraxacum officinale (leaves) were collected within 12 transects along the state road No. E77 near Chyzne, Sothern Poland. The transects were located on the eastern and western side of the road (downwind and upwind towards prevailing winds), at the following distances from the road: 5, 50, 100, 300 500 and 600 m. Total concentrations of Cr, Cu, Ni, Pb, Sb and Zn in the plant material were determined. The studied species accumulated trace metals in the similar amounts. Statistically significant differences in metal concentrations between two plant species were observed only in the case of Cu and Pb. Copper concentrations were higher in the common dandelion, while the moss Pleurozium schreberi accumulated considerably higher amounts of Pb. There is a statistically significant negative correlation between the trace metal concentrations in plants and the distance to the road. There are also statistically significant differences in concentrations of Cr, Cu, Ni, Pb and Zn in the common dandelion between the samples collected from the opposite sides of the road: upwind/downwind towards the prevailing wind direction at the distance up to 300 meters. The concentrations are higher on the downwind side of the road.
