Tree bark was used as a biomonitor to evaluate past atmospheric contamination in and around Stassfurt in Saxony-Anhalt, Germany. Forty-three outer and inner bark samples, predominantly oak (Quercus), were collected. For comparison purposes, bark of the same tree species was collected in reference areas in Saxony-Anhalt and nationwide in Germany. Concentrations of 53 chemical elements, Pb isotope ratios, as well as polycyclic aromatic hydrocarbons (PAH), polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) are reported. Based on the air quality index (AQIB), the outer tree bark concentrations of Ca, Al, Sr, Ti, S, W, Na, Cu, U, Zr and Rb indicate very high atmospheric ‘contaminant loads’11‘Contaminant load’ is used in a very general sense, and includes, in this case, the concentrations, apart from known contaminant elements (e.g., As, Cd, Hg, Pb), and those of essential elements (e.g., Fe, K, Mg, N). in both the urban and surrounding areas. A high ‘contaminant load’ was determined for P, Th, Fe, Be, Ba, Li, Mg, Cs, Mo, Ga, Sn, Ni, As, Ge, Nb, Ag, Zn, Se, N and Co. The Pb, V, Hg, Cd and Mn concentrations correspond to an average ‘contaminant load’ for the city area, whereas concentrations of Pb, Hg and Cd in the surrounding area correspond to a high ‘contaminant load’. The PCDD and PCDF loads are average to high throughout the study area, while the PAH loads are higher in the city than in the surrounding area. Data for the Pb isotope composition show that the Stassfurt sites have ratios that differ from the German mean, and are typical for Saxony and Saxony-Anhalt regions.To assess the atmospheric ‘contaminant load’ of the different sites in the city, an air quality index (AQIB) was calculated from the outer bark data and plotted on a map of the city. The mean atmospheric ‘contaminant load’ of Stassfurt is above the mean ‘contaminant load’ of the comparison sites in all parts of Germany. A bioaccumulation index (BAIB) for the inner bark was also calculated and plotted on a colour map. The bioaccumulation in inner bark indicates a plant availability of contaminants in the environment and their uptake by the tree. Comparison of the distribution patterns of the air quality index with the bioaccumulation index confirms the influence of the different contaminant sources in the study area.