Bestimmung von Dioxinen, Furanen, dioxinähnlichen PCB und Indikator-PCB in Fichten- und Kieferntrieben aus der Umweltprobenbank des Bundes
Körner, Wolfgang; Schädel, Silke; Waller, Ulrich; Köhler, Jutta
Augsburg: Bayerisches Landesamt für Umweltschutz, 2005. - 51
Abstract
In Germany, up to now there is a lack of consistent and comparable data for the time dependent behaviour and spatial distribution of dioxin-like and indicator PCB in ambient air, deposition and plants. The aim of this study was to improve the data on atmospheric entry of PCDD/PCDF, dioxin-like PCB and non dioxin-like PCB by analyzing spruce and pine shoots from different locations and years by retrospective monitoring.
The survey was conducted in cooperation of the Bavarian Environmental Protection Agency (LfU) with the Federal Environmental Agency with representative archived samples of one-year old spruce and pine shoots (Picea abies and Pinus sylvestris) from the German environmental specimen bank. Two sets of samples from two locations in urbanized areas in western and eastern Germany (Warndt and Duebener Heide Mitte, respectively) were investigated as time series. Further, samples of spruce shoots from seven different rural locations from the last years were analyzed in order to get an overview about the spatial distribution of the corresponding groups of substances.
The analytical results of the samples from the two urbanized areas clearly show that the atmospheric contamination with chlorinated dioxins and furans has declined by approximately 75 % between 1985 and 1997 in Warndt and by about 40 % in Duebener Heide Mitte between 1991 and 1995. However, concentrations stayed virtually constant at both locations from 1997 to 2004 at a level of about 1 ng WHO-TEQ/kg dry matter. Similarly, the investigation of spruce shoots from rural locations between 2000 and 2004 did not reveal a temporal trend at any site.
At the urbanized location Warndt the six indicator PCB as well as the twelve dioxin-like PCB according to WHO revealed a decline by 75 % between 1985 and 1997. After 1997, the PCB levels stayed virtually constant. At the location Duebener Heide Mitte a decrease of PCB concentrations in pine shoots of about 60 % was detected between 1995 and 2002.
In all analyzed samples of spruce shoots from all locations the dioxin-like PCB had a relevant contribution to the total WHO toxicity equivalent (PCDD/PCDF + PCB). In most samples, the contribution of dioxin-like PCB was between 21 and 41 %. In the samples from three rural sites the TEQ contribution of PCB was higher and similar to the TEQ value of PCDD/PCDF.
In the investigated pine shoots from the urbanized site Duebener Heide Mitte the contribution of dioxin-like PCB to total TEQ was 15–28 % and thus significantly lower than in spruce shoots from the different locations.
In all samples except one PCB 126 contributed to more than 80 % to the PCB-TEQ.