The epiphytic lichen Lecanora conizaeoides was used as a monitor organism of airborne metals around an industrial area (a steelworks and an iron foundry) at Frederiksvaerk, Denmark. Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, V and Zn were determined by atomic absorption spectrophotometry and K and Na by flame emission techniques. SO 2 air pollution levels were estimated by the distribution of lichen species with different SO 2 sensitivities. A similar regional variation was found within the Frederiksvaerk area of concentrations of the heavy metals Cd, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn, showing increasing concentrations in Lecanora conizaeoides towards the pollution sources. The order of the maximum enrichment factors was: Cd74, Pb 62, Cu 35, Cr 34, V 31, Fe 28, Mn 28, Zn 26 and Ni 9. The air pollution in the area results in elevated concentrations of heavy metals in Lecanora conizaeoides within a radius of at least 3 km from the industrial area.