PCDDs, PCDFs, and metals in selected Danish soils.

Topsoil samples from five locations in Denmark were collected and analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and selected heavy metals. The upper soil layers contained elevated concentrations of PCDDs, PCDFs, Pb, Zn, and Cu compared to the lower layers. The soil contents of PCDDs plus PCDFs were closely related to Pb contents. Higher concentrations were found near urban areas relative to strictly rural locations. From the presented data the provisional Danish background content of PCDDs plus PCDFs is estimated to be 4-7 micrograms m-2 in the topsoil of coniferous forests.