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Veröffentlichung Results of the second national forest soil inventory in Germany - Interpretation of level and stock profiles for PCDD/F and PCB in terms of vegetation and humus type(2018) Pandelova, Marchela; Bussian, Bernd M.; Henkelmann, BernhardPolychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) were detected in 86 humic topsoil layers and in a subset of 11 randomly selected top mineral forest soils at the depths of 0-5 cm and 5-10 cm collected from different federal states of Germany. The distribution of these persistent organic pollutants (POPs) in humic topsoils with respect to vegetation cover (coniferous vs. deciduous vs. mixed), total organic carbon (TOC), altitude and latitude data was investigated. There is cross correlation between the contents and TOC while the correlation with latitude indicates higher abundances of POPs in central Germany where there is high population density accompanied with industrial activities. The calculated stocks suggest that humus type (mor, mull, or moder) in conjunction with forest type can explain the relative POPs abundances in different soil layers. Generally, humic topsoils show highest contents of POPs compare to the two mineral soils with a ratio of 100:10:1. However, the stock humic layers of coniferous stands contribute about 50% to the total stock, whereas at deciduous stands the stock is mainly located in the upper mineral soil layer (0-5 cm). The soil-water distribution coefficients (Kd) were calculated to estimate the potential translocation in the different soil types. The Kd values vary among the PCBs and PCDD/Fs congeners and are most variable for humic topsoils. There is pronounced chemical abundance in the top mineral soils with increasing Kd and this points to non-water bound transport processes for superlipophilic compounds. © 2017 Elsevier B.V. All rights reserved.Veröffentlichung Long-term data for PFAS in soils from German ecosystems, including TOP assay(2023) Bandow, Nicole; Koschorreck, Jan; Wellmitz, JörgIn this study, soil top layers from the German Environmental Specimen Bank (ESB) covering a period from 2002 to 2018 and 11 sampling sites representing four ecosystem types were analysed for 24 PFAS (11 PFCA, 7 PFSA, and 6 precursors), including the total oxidizable precursor (TOP) assay. Median (Sigma)PFAS levels before and after TOP assay ranged from 0.31 to 19.7 (micro)g/kg dry weight (dw) and 0.32 to 20.4 (micro)g/kg dw, respectively. The most frequently measured PFAS above LOQ were PFOS and PFOA, which were present at concentrations above 0.1 (micro)g/kg dw in each sample. Both accounted, on average, for half to two-thirds of the total identified PFAS load at most sites. The investigated samples from the near-natural and forestry ecosystem types each had significantly higher PFAS levels than those from the urban-industrial ecosystem type, while samples from the agricultural ecosystem type did not differ distinctly from the others. Increases of median ΣPFAS levels after TOP assay ranged up to slightly >20 %, indicating that precursor compounds do not play a major role in the substance spectrum of German ESB soil samples from different ecosystem types. Total organic carbon (TOC) content in analysed samples ranged from about 1 % in sandy soil to >40 % in litter layer and showed a strong positive correlation with PFAS concentrations. It is therefore highly recommended that TOC content is reported along with PFAS levels in soils. PFAS trend analysis for nine sampling sites before and after TOP assay showed that concentration levels at most sites have remained more or less stable for the sampled period of almost two decades. The constant PFAS levels in soil samples indicate that PFOS and PFOA regulations have not yet had a positive effect on the exposure situation in this environmental compartment. ©2023 The Authors.