Content of Hg in soil and Solidago virgaurea plant samples collected in the neighbourhood of 3 arterial roads in Poland (distance up to 200 m, depth up to 100 cm) was detd. by using an Hg analyzer. The highest Hg content was found in the surface layer of the soil either close to the road or 50-100 m remote from the road axis (0.229 or 0.237 ppm, resp.). The Hg contents in the plant samples were remarkably lower (up to 0.043 ppm). The contents detd. were lower than the values accepted as natural.