Testing the applicability of dendrochemistry using X-ray fluorescence to trace environmental contamination at a glassworks site

The potential of dendrochemistry as a tool for tracing anthropogenic contamination at a glassworks site in southeastern Sweden was investigated through a multidisciplinary approach combining continuous high-resolution time series of tree rings and sediment profiles. Tree cores from Scots pine (Pinus sylvestris), Norway spruce (Picea abies) and European aspen (Populus tremula) were analysed for their elemental composition using an energy dispersive X-ray fluorescence (ED-XRF) technique. Sediment cores were sampled along a transect extending from the pollution point source to unpolluted areas and analysed using core-scanning-XRF (CS-XRF). High contaminant concentrations in the soil were found for As (≈2000 ppm), Pb (>5000 ppm), Ba (≈1000 ppm) and Cd (≈150 ppm). The concentrations decreased with depth and distance from the pollution source. The dendrochemical analyses revealed alterations in the Barium, Chlorine and Manganese profiles, allowing the identification of seven potential asynchronous releases from the glassworks. Our results suggest that differences in the response of tree species to elemental uptake together with soil chemical properties dictate the success of dendrochemistry as an environmental monitoring tool.