Biologische Sanierung von Rüstungsaltlasten

Many sites of former ammunition plants are contaminated with the explosive 2,4,6-trinitrotoluene, its derivatives and reduction products. Such nitroaromatic compounds have a high human and ecotoxic potential. Plant uptake of these organic pollutants is known and could be confirmed under field conditions. In this paper rhizospheric soil was analyzed to characterize the effect of vegetation on TNT-contaminated soil. Common beans (Phaseolus vulgaris) were used as test plants. The experiments were performed on two areas with different TNT concentrations. The data reveal a significant decrease of extractable TNT in rhizospheric soil by a factor of 5 to 6 during the vegetation period. On the area with high TNT concentration, an enrichment of nitroaromatic compounds in root tissue was found compared to the rhizospheric soil. Aminodinitrotoluene could be confirmed as the primary pollutant in the root. These results refer to a potential application of plants to biological remediation of soil contaminated with ammunition-specific pollutants.     

Untersuchungen zur Aufnahme von HCB und Pyren durch den KompostwurmEisenia fetida und ausgewählte Regenwurmwildarten

The main issues of the studies described were the validation of a test design for the assessment of the bioaccumulation potential of environmental pollutants and the applicability ofEisenia fetida as a model-organism and artificial soil (OECD) as a standard test substrate. The test organisms used wereE. fetida of our own breeding stock andAllolobophora caliginosa, Allolobophora chlorotica, Allolobophora longa and Lumbricus rubellus sampled from a field site. Test soils used were the artificial soil (OECD) and a BBA field soil. Soils were each contaminated with 10 mg HCB and Pyrene per soil dry-weight. Within the test period of 4 weeks, samples were taken weekly for residue analysis in the worms and soils. Bioaccumulation factors (AF) calculated forE. fetida and the free-living species were in the range of 10–17 (HCB) and 0.9–1.7 (Pyrene) depending on the soil used. By re-calculation of the concentrations in soil to concentrations in soil water, the resulting bioconcentration factors are compared with published BCF values determined from QSAR’s of other worm species and fresh water fish. It could be concluded that the existing earthworm tests (OECD 1984, ISO 1998) represent an appropriate design for testing the bioconcentration potential of chemicals in soil.     

Leitfaden zur Beurteilung von Boden-Kontaminationen

This article investigates to which extent presently obtainable data can sufficiently evaluate soil contamination. Relevant data pertaining to this question are tabulated. Risk assessments are made for particular contaminations on the basis of the compiled data. The proposed procedure is a guideline for the practical evaluation of cases of soil contamination by organic pollutants. Analyses are made for soil compartments, including risk assessments for groundwater. Evaluations are directed at protection of resources and plant growth. The project aims at facilitating the recognition of research deficiencies and at suggesting appropriate measures.     

Untersuchungen zur Charakterisierung von Brandrauch

The aim of this work is to clarify if there is a correlation between fuel and its organic combustion products. To acquire homogenous data sets for our investigations, we analysed only the measurements of the “Forschungsstelle für Brandschutztechnik” at the University of Karlsruhe. All compounds with a similar structure were grouped and structural indices were ascribed to them. This also made it possible to obtain information about the frequency of occurrence of a set of substances in fire smoke. The kind of analytical measurements used by this institute provided no or only little information about inorganic compounds, highly volatile substances like acrolein or vinyl chloride, and very poorly volatile substances (e.g. polycyclic aromatic hydrocarbons). We found that benzene, methylbenzene, ethenylbenzene and ethylbenzene are always present in fire smoke. The formation of these typical compounds is described by a model. Aside from these compounds which are typically related to the smoke from fires, substances are always observed which are typical for a distinct fuel. Many compounds which are expected to be in the smoke are highly carcinogenic. Therefore, it is necessary for people with a high exposure to the smoke of fires, e.g. firemen, to protect themselves efficiently. In order to obtain more information about the risks to health of fire smoke, toxicological investigations will be necessary.     

Vorschlag zur Auswertung von PAK-Kontaminationen

The behaviour of this group of substances may be considered as an example for the ubiquitous occurence of xenobiotics in the environment. Regrettably, the measurements presented in numerous publications often cannot be directly compared with each other. A first step towards harmonization can be achieved by referring the measuring programmes or the presentation of results to the six aromatics of the German Drinking Water Ordinance (TWV) (Σ6) or the sixteen compounds of the EPA list. The tendency of the PAH group to fractionation in air, water, and soil as well as in some cases during analysis must be taken into acount. In this respect, the first six aromatics of the EPA list are only partially suitable for comparisons of results. The six TWV aromatics in soils, sediments, aquatic suspended solids, and sewage sludges, and to a certain extent also in airborne dust, make up a mass portion of C_Σ6=40–50% of the Σ16 according to EPA. For Fluoranthene (Fluo) and Benzo(a)pyrene (Bap) as quide parameters, concentration quotients [single aromatic versus (Σ6)] may be given as estimates, which are on average C_Fluo=33%, and C_Bap=13%. By means of these quotients it is possible to calculate the values for the whole list by means of the data of the single aromatic C_Fluo×3=C_Σ6, or C_Bap×7,7=C_Σ6, and as a check C_Fluo/C_Bap=2,5. For estimating purposes, the relation between the two lists may be assumed als C_Σ6×2=C_Σ16. These estimating values apply to mixes of PAH, which originate from many single sources (emitters), are transported through the atmosphere with dust and settle, and/or enter water bodies after being washed from road surfaces. The estimates serve as plausibility check and for extrapolation, but they cannot replace the analysis for individual substances in the identification of the pollution source or in the study of their environmental behaviour.     

Bioreaktoranlage zur reproduzierbaren Bildung von Biofilmen

Biofilms frequently appear, they are sometimes useful and sometimes disturbing. For the investigation of biofilms, it was necessary to reproduce them in specific bioreactors. Furthermore, useful media and analytical methods have to define the influence of biocides and other substances. The gravimetric analysis of microbe-formed polysaccharides in water samples and biofilm makes it possible to recognise successful treatments. These conditions are described here. Using these instruments it was possible to build up reproducible biofilms, to test and optimise them in lab examinations. In view of the expected EU Biocide Directive, this process offers possibilities for searching and verifying the suitability of biocides and other substances.     

Untersuchungen zur Umweltchemie,Kontaminationserkundung und -bewertung

Leachate and groundwater have been investigated at a site contaminated with ammunition residues. The presence of nitroaromatic compounds and their degradation products was investigated by GC-MS-screening methods. Nitro-, amino-nitro-, and amino-aromatic substances of the ?TNT type“ were analyzed along with polar substances such as 3,5-dinitro-o-cresol and 4,6-dinitro-o-cresol. Investigation of these primary metabolites is important for risk assessment and for determining clean-up measures     

Ein Ansatz zur Methodik der vergleichenden Bewertung von Bodenbelastungen

An evaluation of the degradation of soils can be performed in several ways. Here, one way will be demonstrated beginning with the definition of the objects which are to be evaluated, continued with the definition of protection aims and the derivation of indicators. Objects together with indicators provide the frame within which a multicriteria assessment, has to be performed. Often no deterministic quality function is available, so that the concept of partially ordered sets is suggested. This concept is demonstrated by an example of an evaluation exercise performed for the environmental protection agency in Baden Württemberg. A result is that the use of arbitrarily defined quality functions may lead to erroneous statements.