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ISBN: Im Zuge der Harmonisierung der Rechtsvorschriften der Mitgliedsstaaten der Europäischen Gemeinschaft wurde im September 1996 die Richtlinie 96/59/EG des Rates über die Beseitigung polychlorierter Biphenyle und polychlorierter Terphenyle (PCB/PCT) verabschiedet. Ziel dieser Richtlinie ist die Angleichung der Rechtsvorschriften der Mitgliedstaaten über die kontrollierte Beseitigung der PCB, die Dekontaminierung oder Beseitigung PCB-haltiger Geräte und die Beseitigung von PCB-Abfall. In der Bundesrepublik Deutschland wurde mit der Verabschiedung der PCB/PCT- Abfallverordnung vom 26. Juni 2000 die EU-Richtlinie umgesetzt. Entsprechend der PCB/PCT-Abfallverordnung wird für PCB-haltigen Abfall ein Grenzwert von 50 mg/kg festgelegt. Beim Haupteinsatzgebiet der PCB - als Isolierflüssigkeiten in Transformatoren - ist die Bestimmung des PCB-Gehaltes durch DIN-Normen geregelt. Polychlorierte Biphenyle wurden auch als Weichmacher in Dichtungsmassen und Kunststoffen, z.B. in Kabelummantelungen, und als Flammschutzmittelanstrich für Holz eingesetzt. Für feste Abfallmatrices gibt es keine verbindliche Prüfvorschrift. Ziel des Projektes war die Erarbeitung und Validierung eines Prüfverfahrens zur Bestimmung von PCB und PCT in organischen Abfallmatrices wie Kabelshredder und Altholz.
The Of/Oh-horizons of 447 forest stands in Germany were evaluated for concentrations and spatial distribution of selected polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs). While concentrations of dichlorodiphenyltrichloroethane (DDT) and PCBs show similar spatial distribution patterns for all measured compounds within each compound class, significantly different distributions were identified for concentrations of low-molecular-weight PAHs [2- and 3-ring PAHs plus fluoranthene (FLA) and pyrene (PYR)] in contrast to high-molecular-weight PAHs (4–6-ring PAHs without FLA and PYR). Maxima of persistent organic pollutant (POP) concentrations could be mostly explained by specific locatable sources. Because of the slow degradation rates of these target substances, this is especially relevant for historic contamination sources, such as extensive 1980s DDT usage in the former German Democratic Republic and industrial facilities that produced hexachlorobenzene (HCB) or PCBs. A contribution of ubiquitous background pollution derived from long-range atmospheric transport is likely for some compounds in the studied area, e.g., DDT in the western part of Germany and dieldrin. However, most target compounds appear to be mainly sourced from local or regional emissions. This is supported by the absence of clear dependencies between POP concentrations and most evaluated environmental and local parameters. We suggest that these results generally reflect the distribution of POPs in densely populated and industrialized countries located in temperate regions.
Samples of 474 forest stands in Germany were analysed for concentrations of polycyclic aromatic hydrocarbons (PAHs) in three sampling depths. Enhanced concentrations were mainly found at spots relatively close to densely industrialized and urbanized regions and at some topographically elevated areas. Average enrichment factors between mineral soil and humic layer depend on humus type i.e. decrease from mull via moder to mor. Based on their compound-patterns, the observed samples could be assigned to three main clusters. For some parts of our study area a uniform assignment of samples to clusters over larger regions could be identified. For instance, samples taken at vicinity to brown-coal strip-mining districts are characterized by high relative abundances of low-molecular-weight PAHs. These results suggest that PAHs are more likely originated from local and regional emitters rather than from long-range transport and that specific source-regions can be identified based on PAH fingerprints.