The lead, copper and zinc content of tree rings and bark. A measurement of local metallic pollution.

Analysis of samples of wood taken from different tree rings for lead by atomic absorption spectrometry showed that there was little correlation between the sample site or ring age and air borne lead concentrations. However, the concentration of lead in tree bark at several sites was particularly sensitive to traffic flow at that site. The concentration of lead, zinc and copper in the tree bark decreased with increased distance from the road and with height above the ground. The method offers a simple technique for effectively tracing atmospheric metal concentrations.