Neue Bewertung bei den Toxizitätsäquivalenten für Dioxine/Furane und für PCB durch die WHO

While the large amount of data available makes it possible to provide a statement concerning the effects of PCDD/PCDF on the WHO TEF-reappraisal regarding the observance of dioxin emission values from waste incineration, similar values for PCBs could not be determined accurately or could only be estimated roughly for the WHO, because only limited measurement values are available for these substances. Thanks to the present availability of such measurement values from the MVA in Bielefeld-Herford, Germany and the MVR in Hamburg, Germany, it is now possible to determine a direct relationship between the low PCDD/PCDF values and the 12 different PCBs which are taken into consideration by the WHO. As the results of these investigations have shown, the statement in Section 2 claiming that there are generally only very low levels of PCDD/PCDF emissions stemming from waste incineration plants, and that the 12 additional PCBs considered by the WHO as well as the WHO TEFs lead to no relevant increase in the evaluation/calculation of the actual emission values nor to a value above the dioxin (I-TEQ) threshold value as established in the 17th BImSchV (Germany Federal regulations responsible for protecting the population from emissions), can be confirmed. A dominant role of the WHO PCB-TEQs is seen to be played by the PCB-126. The exhaust gas measurements in waste incineration plants might therefore already be sufficient if merely the dioxin-like PCB-126 values were to be used in the calculation of the dioxin I-TEQ.     

Einführung in die Neuregelungen für Zulassung und Gebrauch von Pestiziden

In the following articles, the revision of the European regulations on the admission and use of pesticides is reported. Authors from the German environmental protection agency, the producers of chemicals for crop protection, and of a non-governmental organisation clarify their views on the revision with respect to a number of questions.     

Entwicklung von Prüfwertempfehlungen für ausgewählte Schadstoffe zum Schutz des Bodens als Lebensraum für Bodenorganismen

Goal and Scope

In the German Federal Soil Protection and Contaminated Sites Ordinance there are no ecotoxicological trigger values for the protection of soil as a habitat for soil organisms. The objective of this study was to derive preliminary trigger values for the habitat function of soils. This was done by collecting data on the impact of priority pollutants on soil organisms and plants followed by the parallel use of the Factorial Application Method (FAME) and Distribution Based Extrapolation (DIBAEX) and a final verification of the plausibility of the calculated trigger values by means of an ecotoxicological test battery.

Methods

Data on the effects of pollutants on soil organisms and plants were recorded in a specific data base (Soil Value). Subsequently, we derived so-called ‘working trigger values’ using the extrapolation methods FAME (factorial application method) and DIBAEX (distribution based extrapolation). In the second phase of the project, we verified experimentally the plausibility of these values by means of an ecotoxicological test battery. Test substrate was a sandy soil with low sorption capacity and organic carbon content which was mixed with fresh pollutants (e.g. heavy metal salts) and polluted soil material from contaminated sites (aged contamination), respectively. Organisms tested were microorganisms, plants, earthworms, springtails and nematodes.

Results and Conclusions

We calculated working trigger values for 12 pollutants based on 900 datasets compiled in he data base. The laboratory investigations showed the freshly added contaminants to be less strongly adsorbed to the soil than those added by the use of contaminated soil material. Nevertheless, aged contaminations displayed often the same inhibitive effects as the freshly added chemicals. The results achieved in the second phase of the project were also recorded in the Soil-Value database. Based on the new data set, final trigger values were derived for the experimentally tested substances.

Outlook

The procedure described in this contribution exemplarily for copper can be used for the derivation of recommended trigger values for the pathway soil ? soil organisms. Besides copper, preliminary trigger values were derived for zinc, mercury, lead and HCH.     

Nativ-basierte Grundöle für die Produktion von Kühlschmierstoffen

Aims and Scope

Compared to mineral oil products, cooling lubricants based on fatty acid esters have technological advantages. Moreover, they are more environmentally compatible and make a contribution to a sustainable economy. Nevertheless, they are rarely applied in practice, because of their comparably high price, that is based on raw-material and synthesis costs. Alternatives concerning raw-materials and synthesis pathways are considered and properties of resulting ester products are compared.

Methods

The investigations aimed at three fatty acid-2-ethyl-hexylesters that were synthesized in an enzymatic-catalytic routine based on peanut oil, suet, and waste edible fat and at esters that were conventionally produced from animal and plant fats and 2-ethyl-1-hexanol. Physical properties, fatty acid patterns, contents of free fatty acids, as well as oxidative and hydrolytic stabilities were determined. Thermolysis experiments were performed.

Results

The physical properties of the seven esters, density, viscosity, pourpoint, and flash point, were comparable and gave reason for the assumption, that the products could be used as basis oils in lubricant formulations. Hydrolysis stabilities of the esters were high and thermal stress did not point at high potential of hazardous compounds formation. Especially the enzymatic-catalytically produced esters showed deficits concerning oxidation stabilities and free fatty acid contents.

Outlook

For practice it will be necessary to define minimum qualities for raw-materials and resulting ester oils to be used as lubricant basis oils. Moreover, processes have to be developed, that yield high quality ester products from waste edible and animal fats without loosing the advantage of low-cost raw-materials by high production and refinement costs. Surely, one contribution is the further development of the energy-saving enzymtic alcoholysis for ester production.     

Stoffflussanalyse von quartären Ammoniumverbindungen für die Schweiz

Background, aim, and scope Compared to other micropollutants such as pesticides or pharmaceuticals, less attention has been paid to biocides so far. A prioritisation of the biocides currently used in Switzerland in terms of pollution of waters revealed that quaternary ammonium compounds (QAC), the isothiazolinones chloromethylisothiazolinone and benzisothiazolinone as well as Irgarol exhibit the highest risk potential. The QAC benzalkoniumchloride (BAC) and didecyldimethylammoniumchloride (DDAC-C10) are used in considerable amounts and have a high biological activity. Materials and methods The emissions of selected QAC in waters and soil and the predicted environmental concentrations (PECs) were estimated by means of a substance flow analysis (SFA). The study was based on data from the Swiss products register, on literature, contacts to producers and users as well as on own assumptions. Results and discussion The consumption of BAC (four homologues) and DDAC-C10 in biocidal applications in Switzerland amounts to 90 and 30 tons annually. The most important applications are disinfectants for public health areas, food and feed areas as well as wood preservatives. The total emissions to the environment of all five substances account for approximately 11?t/a. The PECs in surface waters and sediments vary from values slightly lower than the predicted no-effect concentration (PNEC) to roughly three orders of magnitude below the PNEC. However, concentrations above the PNEC are possible at certain locations, particularly downstream of wastewater treatment plants (WWTP) effluents and sewer overflows. Effects on aquatic organisms can therefore not be excluded. Three BAC homologues could not be assessed, as there were no PNEC values available. Conclusions The contribution of emissions from WWTP (punctual emissions) to the environment is only about one tenth and relatively low compared to diffuse emissions. This means that measures for the emission reduction focussing only on end-of-pipe solutions in WWTP will not reduce the emissions significantly. Moreover, for the evaluation of measures, attention has to be paid to the fact that biocides such as the selected QAC are often also applied in non-biocidal applications (e.?g. three times higher volumes in the case of BAC). Recommendations and perspectives SFA serves as a useful tool for early recognition of environmental problems caused by chemicals. This allows recommending appropriate risk reduction measures in the production, the use and the end-of-life phase. It is advisable to use the SFA already in the development stage of chemicals and later on as a quality control tool. The relevant sources of chemicals and sinks in the environment can thus be determined in complex systems, even in absence of extensive measurements or product registers with consumption figures by means of estimations and scenarios.     

Neue horizonte für die chemie

The term ‘sustainable development’ is defined and discussed with regard to its significance and its application in the field of chemistry. This is presented using the synthetic organic chemistry as an example. A review of the history of chemistry indicates clearly the necessity for further developments in the course of concepts involving sustainability. Following the eras of bituminous coal tar and mineral oil in both of the two past centuries, a search for new raw materials and a reduction in the global ecotoxicological potential for danger is being strived for. Critical contemplations are mandatory in order to avoid making this term ‘persistence’ into a keyword. Consequently, one must take into consideration the field of research and development as well as reflecting about the classification of chemical and scientific research projects, and their political as well as social relationships. Aside from the new methods of synthesis, this will also require the formulation of other decision-relevant criteria.     

Terrestrische ökotoxikologische Testmethoden für die Tropen

Goal, Scope, and Background

Soil organisms play a crucial role in the terrestrial ecosystem. Plant Protection Products (PPPs) are known to affect soil organisms and might have negative impacts on soil functions influenced by these organisms. Little research has been done to day on the impact of PPs on tropical ecosystems. Therefore, in this study it was investigated whether fate and effects of pesticides differ between tropical and temperate regions and whether data generated under temperate conditions can be used for the Environmental Risk Assessment (ERA) in tropical regions.

Methods

In the first part of this study, the effects of two fungicides (Benomyl and Carbendazim) and one insecticide (lambda-Cyhalothrin) on soil invertebrates (i.e. earthworms and arthropods) were evaluated in laboratory tests modified for tropical conditions (temperature, soil, test species). Besides using some native species, the tests were done mainly with two (temperate and tropical) strains of earthworms (Eisenia fetida) and the peregrine isopod speciesPorcellionides pruinosus as standard test species. The chemicals were spiked in two natural and two artificial soils. A tropical artificial soil (TAS), containing a tropical fern product (Xaxim) or coconut coir dust as organic matter, was developed in this study.

Results and Conclusions

The results from the laboratory tests showed that all three test chemicals differed from those gained under temperate conditions. In the case of the fungicides the toxicity was lower but in the case of the insecticide higher under tropical than under temperate conditions. The native tropical earthwormPontoscolex corethrurus reacted more sensitively against Carbendazim in comparison to the standard test speciesEisenia fetida.

Recommendation and Perspective

Details of the environmental risk assessment of the three model chemicals based on the results of the laboratory described here (and including the results of higher tier tests (semi-field and field tests)) will be described in Part 2 of this series     

Imprägnierte Filterpapiere für die Wasserreinigung

With special filter materials it is possible to eliminate the heavy metals lead, copper and nickel and arsenic from water by sorption resp. chemical bounding. After a reaction time of 24 hours the reduction rates were between 97% and >99,9%.     

Terrestrische ökotoxikologische Testmethoden für die Tropen

Goal, Scope, and Background

Soil organisms play a crucial role in terrestrial ecosystems. Plant Protection Products (PPPs) are known to affect these organisms and might have negative impacts on soil functions influenced by these organisms. Little research has been done to day on the impact of PPPs on tropical ecosystems. Therefore, in this study it was investigated whether the effects of pesticides differ between tropical and temperate regions and whether data generated under temperate conditions can be used for the Environmental Risk Assessment (ERA) in tropical regions.

Methods

The effects of one fungicide (Carbendazim) and one insecticide (lambda-Cyhalothrin) on soil invertebrates (earthworms and arthropods) and functional parameters (organic matter (OM) breakdown, feeding rate) were evaluated in semi-field tests using Terrestrial Model Ecosystems (TMEs) and in field tests using litter-bags. The soil for the TMEs was extracted from the same site near Manaus (Amazonas, Brazil) where the field test was conducted (see Part 1, Römbke et al. 2005 〈DOI: http://dx.doi.org/10.1065/uswf2004.12.088.1〉). The soil was acid clay, typical for tropical regions. In the TMEs the standard test species as well as native tropical species were introduced. Several application scenarios, selected according to their relevance for practical conditions, were realized in TME-tests and field (duration: 150 and 365 days, respectively). Finally, an Environmental Risk Assessment (ERA) for the two chemicals was performed.

Results and Conclusions

The results from the TME-tests show that both test chemicals (depending on their concentration) had toxic effects on the tested organisms and organic matter breakdown, but not on the feeding rates. In the field organic matter breakdown was affected for some time too, but effects on single species were, with one exception (the native earthworm Andiorrhinus amazonicus) not observed; a result probably influenced by the small size of the test plots. Observed differences in OM breakdown between control and treated TMEs were often significant, while due to the higher variability even with differences >10% between means this was not the case in the field.

Recommendation and Perspective

According to the preliminary results of the Environmental Risk, Assessment presented here, the use of the three model chemicals in the tropics (e.g. in Brazil) can cause a damage to the environmental compartment soil. Therefore, a more detailed investigation of these PPPs is recommended, in particular a better evaluation of the exposure (residue analysis). In general, the work performed in Amazonia can be summarised as follows: (1) Depending on the properties of the PPP, the effects of pesticides in tropical resp, temperate regions can differ. (2) If a PPP is going to be used in the tropics, data from tests modified for these conditions should be performed and their results should be incorporated in an Environmental Risk Assessment (ERA) for tropical regions.     

Aktive Stoffe als Handlungsoption gegen die Verschleppung von Organismen durch Seeschiffe?

Background and Scope

The marine shipping lanes have become the most important path for the invasion of foreign aquatic organisms. The increasing global trade results in an increase in the number of marine vessels. Without any protective measures, with every ship carrying foreign organisms the risk of biological invasions will rise.

Results

The International Martime Organization (IMO) of the United Nations developed a convention to reduce the transfer of organisms with ballast water. After the entry-into-force of this convention the fleet of the world has to be equipped with effective ballast water management technology before 2016. This article discusses potential options for action. To comply with the limit values of the ballast water convention, the current state of the art demands the use of active substances. Any decision on the approval of active substances used for ballast water treatment and the environmental impact assessment lies with the IMO. Proposed to day are UV-radiation, active chlorine, active oxygen, the creation of biocides through electrolysis and a change in gases contained in the ballast water. The technologies and the potential risks are presented.

Conclusions

Despite the introduction of an approval procedure by IMO any reliable assessment of the real risks involved in the use of biocides is impossible, as the risk assessment approaches have still to be developed. On the regulatory level, the main focus in data requirements for the risk assessment is on a comprehensive testing of the toxic potential of the biocides proposed. Strategies for the identification and evaluation of the chemical resulting from the treatment of limnic, marine and brackish water are not fully developed. An integrating assessment of risks involved in the introduction of foreign organisms versus the toxic effects of the substances used or created during treatment is still missing.     

Eier der Flußseeschwalbe (Sterna hirundo) als Indikator für die aktuelle Belastung von Rhein, Weser und Elbe mit Umweltchemikalien

In 1995, common tern (Sterna hirundo) eggs from the big German rivers, the Rhine, Weser and Elbe were collected to study the contamination with organochlorines and mercury. We found distinct differences between the rivers: common tern eggs from the Rhine had higher concentrations of PCBs and HCHs, while eggs from the Elbe had higher residues of DDT, HCB and mercury. Also toxic PCB congeners had higher residue levels in the Rhine. Considering all organochlorines, samples from the Rhine also had the highest concentrations, while those from the Elbe were the lowest. With 5.7 μg×g^?1 fresh weight, the ΖCBs had a level endangering breeding success. Fish eating birds should be used as indicators of the contamination of the rivers with environmental chemicals and should be included in monitoring programmes.     

Versuchsanlage zur energetischen Beurteilung von Substraten und Kofermentaten für Biogasanlagen

Goal, Scope and Background

Worldwide energy requirements are constantly increasing. Rising prices and the necessity to secure the future energy supply have led the decision-makers in politics and economy to focus on the more intensive use of their own resources. Before the background of possible climatic effects caused by the use of fossil energies, the use of renewable resources as primary energies, with its narrow C-circulation, have gained in importance, particularly in terms of economic aspects. The production of biogas is of specific interest here. It is a sensible ecological investment and a solid source of income for our agriculture.

Material and Methods

The operator uses a complex biological system in a plant with high investment costs. An economic operation is only possible if the process parameters are optimized and the properties of the substrates and the co-ferments are known. For the important determination of the blogas potential, we present an efficient and robust system, which is easy to handle and low cost, that has been developed by the LHL and LLH at the Eichhof. This procedure enables one to make statements on the implementation dynamics and is also suited to judge the fermentation process depending on the size of particles, as the co-ferments are used in a practice-oriented consistency.

Results

With the described fermentation apparatus you can not only assess the potential development of biogas and methane, but also the process of fermentation. The sum-graphs determined allow one to make conclusions on the implementation dynamics and, thus, on the optimization of the process. The advanced equipment makes it possible to determine the process of fermentation and the gas yield under different retention times and digester loads. The determination of the potential of the biogas and also the evaluation of the continuous fermentation are related to a specific correction factor won from the standard.

Discussion

A prerequisite for economic process management is the knowledge of the attainable gas yield and the fermentation process of substrates and co-ferments. A precise calibration is the quality basis for the results achieved with this method, as is the case with other fermentation tests as well. For the tests, a highly homogeneous substrate, which guarantees a continuous biological activity in the digesters, ought to be used. The possibility of determining optimum retention times and digester loads with this equipment makes costly tests with a full scale reactor unnecessary.

Conclusions

All tests run demonstrated that the fermentation apparatus originally developed to determine the biogas yield is absolutely suited to also assess the impact of different digester loads and retention times.

Recommendations

The problem of the suitability and the potential of different materials, the optimum reactor performance and the combination of different processes of energy generation from renewable but also conventional resources will increaseingly become the focus of laboratory tests. The following subjects have to be taken into account:

- Testing different materials on their suitability

- Evaluation security of common and new co-ferments

- Guidelines for mixtures to optimize reactor performance

- Mixtures of different substrates and co-ferments available to a particular operator (also with the help of simulation models)

- Processing changing quantity proportions of plants won from a rotation of crops altered for energy generation

- Other parameters like pre-fermentation, particle size and fer mentation supplements.

Perspective

These tests with a high practical relevance are supposed to contribute to a reliable method of producing biogas, in order to optimize the yield of gas production, but also to find a calibration of less costly procedures like those involving Near Infrared Spectroscopy (NIRS).