Prüfung und Bewertung der Auswirkungen von Pflanzenschutzmitteln auf terrestrische Organismen nach der EG-Richtlinie 91/414/EWG

EU Directive 91/414/EEC describes the authorization procedure for plant protection products. According to annex VI of this directive, the EU member states have to ensure that a plant protection product does not have unacceptable effects on the environment. The data requirements and the function of laboratory and field tests in the assessment procedure are discussed for the terrestrial compartment.     

Prüfung der Auswirkungen von Pflanzenschutzmitteln auf Laufkäfer

The testing procedure for the effects of pesticides on carabid beetles is described and examples are given for important factors, e.g. temperature, type of soil, testing method and physiology of the test animal, which can influence the results of such tests. Risk assessment for pesticides, therefore, has to be carried out by experts. Additionally, a monitoring of effects should be carried out after the registration process in certain cases.     

Untersuchungen zur Eignung von Neutralsalzen als Referenzmittel bei der mikrobiologisch-ökotoxikologischen Bewertung von Pflanzenschutzmitteln im Boden

Goal and Scope

The information value of microbiologicalecotoxicological investigations of pesticides in soil increases if reference compounds with known biocidal effects are included. But those reference compounds used until now often are of remarkable environmental and human toxicity and therefore are difficult to handle. Inorganic neutral salts sometimes were discussed as alternatives, but their suitability needs to be tested before.

Methods

For laboratory experiments some microbial activities in soil were selected whose effects had been proved in several microbiological-ecotoxicological investigations. They include the mineralization of carbon and nitrogen (+ nitrification) as well as the biomass-related parameters dehydrogenase activity and substrate-induced short-term respiration. Several agricultural soils were used to confirm the results.     

Eine Weight-of-Evidence-Studie zur Bewertung der Sedimentbelastung und des Fischrückgangs in der Oberen Donau

Background and aim Despite intensive and continuous stocking and improvement of water quality since the 1970s, fish populations, especially those of the grayling (Thymallus thymallus), have declined over the last two decades in the upper Danube River (Germany). In order to assess 1) possible links between molecular/biochemical responses and ecologically relevant effects, and 2) if ecotoxicological effects might be related to the decline in fish catches in the upper Danube river, sediment samples and fish were collected at different locations and analyzed using a weight-of-evidence (WOE) approach with several lines of evidence. The objective of the presentation is to introduce the conceptual framework and to review results of the ongoing study. As previously addressed by Chapman and Hollert (2006) a variety of lines of evidence can be used in WOE studies. Briefly, 1) a comprehensive battery of acute and mechanism-specific bioassays was used to characterize the ecotoxicological hazard potential. 2) Histopathological investigations and the micronucleus assay with erythrocytes were applied, analyzing in situ parameters. 3) Diversity and abundance of benthic macroinvertebrates and fish as well as 4) persistent organic pollutants, endocrine disrupting substances, limnochemical parameters and the concentration of heavy metals were recorded. To identify organic contaminants a spotential causes of sediment toxicity assays, 5) effect directed analysis was applied.     

HPLC-MS/MS in der Rückstandsanalytik von Pflanzenschutzmitteln

Goal and Scope

Increasing demands from the regulatory authorities of plant protection products for residue analytical methods on the one hand and the need for cost reduction by shorter development times on the other hand have led to a significant displacement of conventional methods (e.g. HPLC-UV or GC-MS) by HPLC-MS/MS with atmospheric pressure ionization (API) in residue analysis since the mid of the 1990s. This development started in the pharmaceutical industries where HPLC-MS/MS had already been used for the quantitation of drugs and their metabolites in plasma since the late 1980s.

Methods

The reason for the high acceptability of HPLC-MS/MS with electrospray ionisation (ESI) or chemical ionization at atmosheric pressure (APCI) compared with alternative methods are shown with respect to analytical quality parameters, compliance with international registration guidelines and economic reasons.

Results and Conclusion

HPLC-MS/MS is being applied for solving ca. 75% of all analytical problems occuring in modern residue analytical laboratories. This technique offers convincing advantages for the determination of plant protection products and their metabolites in various matrices. These are a reduced number of or no clean-up steps after extraction of the samples, high throughput besides high ruggedness, low limits of detection and a large linear measuring range. In addition, several analytes of various chemical classes can be determined within one chromatographic run. Due to the high selectivity there is only little need for additional confirmatory methods. For enforcement purposes HPLC-MS/MS is accepted by the European authorities since 2002. However, due to high costs for instrumentation and specially skilled personnel only few enforcement laboratories have invested into this technology, so far.

Recommendation and Perspective

The importance of HPLC-MS/MS in residue analysis will further increase, as new ionization techniques will enable the analysis of more analytes and as the investment costs will decrease in the future. However, proven conventional methods will still survive in some cases. New concepts, such as parallel HPLC-MS/MS or on-line purification of extracts by column switching which are already widely used in the pharmaceutical industry could help to further increase the throughput. However, for a sound evaluation with respect to their applicability in residue analysis there is so far too little experience.     

Bewertung der Umweltgefährlichkeit von Stoffen

By sending a questionnaire to all companies of the pulp and paper, textile finishing and leather industries in Germany a study ascertained wastewater data concerning the general situation, treatment processes and specific amounts. With these data standard figures used in the EU for the assessment of chemical substances were checked. The volume flows of the industrial sewage treatment were determined for the facilities of all three branches which discharge their wastewater directly to the receiving waters. The 10 percentile score of these facilities amounted to only a quarter of the EU standard figure of 2,000 m³/d. This value is related to a standardised waste water treatment plant within the EU, which treated the wastewater of 200 l/d from 10,000 inhabitants. The analyses of the entire branch in each case yield dilution factors of 20–70% of the EU standard value of 10. Only the full tanning leather companies yielded a dilution factor of 10. The volume flows of the sewage treatment plants of the facilities discharging to the sewer system exceeds 2,000 m³/d in call cases.     

Untersuchung von Abfällen mit biologischen Testverfahren zur Bewertung der Wassergefährdung

Wastes from three different types of waste treatment facilities (slag from a municipal waste incineration plant, slag granules from a pilot plant combining carbonization and incineration, mechanical and biological treated wastes) were examined to determine their hazard potential to different waters sites. The process temperature is seen to be the main difference between the three treatment processes. The wastes were extracted with water according to the German standard DIN 38414 S 4 and additionally at a constant pH value of 4. The leachates were investigated in a battery of aquatic bioassays and characterised physically and chemically. Every leachate revealed in a toxic effect at least in one test. The toxicity of the leachates prepared at a pH of 4 was significantly higher than the toxicity of the leachates prepared by extraction with water without pH adjustment. The leachates of the slag granules showed the lowest toxicity. On the basis of these experimental results, a scheme to derive Water Hazard Classes of wastes, which is presented in part II of this publication, was developed.     

Untersuchung von Abfällen mit biologischen Testverfahren zur Bewertung der Wassergefährdung

Wastes from three different types of waste treatment facilities were examined with bioassays to determine their hazard potential to waters (→Part I). All examined wastes showed toxic effects and have to be classified as hazardous to waters according to section 19g of the German Federal Water Management Act. The toxicity is probably caused by heavy metals in the leachates, especially copper. An evaluation pattern to classify wastes in the German system of Water Hazard Classes is presented. According to this proposal, a classification of the examined wastes into Water Hazard Class 1 seems to be appropriate. This classification does not describe the hazards resulting from the regular disposal on a landfill or from the utilisation of the treated wastes.     

Nutzen und Grenzen von Modellökosystemen zur Erfassung der Wirkung von Schadstoffen auf benthische Lebensgemeinschaften

The aim of this short article is to deliver insight into the prospects and constraints of model ecosystems in the assessment of effects of contaminants on benthic communities, especially the meiofauna. Numerous substances accumulate in sediments and thus a complex contamination exists which is able to impair benthic organisms. Besides direct effects, indirect effects are of importance and should be considered. Changes in competition and predator-prey-relationships lead to a variety of effects in the benthic food web that cannot be explained by direct toxicity of contaminants. In this article two microcosm studies, one with the heavy metal cadmium and one with the veterinary pharmaceutical Ivermectin, are presented which both showed direct as well as indirect effects. A significant change in abundance and composition of the meiofauna community has been observed. The prediction of field-effects of a certain substance as well as the interpretation of field data are the aims of model ecosystems. Both studies proofed that the investigation of meiofauna in microcosms is a promising tool to achieve these aims. Furthermore, microcosms with meiofauna might be able to assist the effect-directed analysis (EDA) in a risk assessment by identifying the effect-causing contaminants of complex environmental samples.     

Bewertung der potenziellen Grundwasserbelastung von deponierten Hochofengasschlämmen

Goal and Scope

Blast-furnace sludge is a waste originating from pig-iron production and contains contaminants such as lead, zinc, fluoride and cyanide assumably contaminating the groundwater by leaching.

Methods

We investigated the chemical composition of 27 samples of landfilled blast-furnace sludge in pore waters which were obtained by the centrifugation of fresh material and elution with water according to DIN 38414 part 4 (S 4).

Results

The pore waters as well as the eluates were neutral to alkaline (pH 7.3 to 10.7) and were dominated by alkali and alkaline-earth metals as well as sulphate and nitrate. The concentrations of all elements and compounds investigated were mostly clearly larger in the pore waters than in the eluates. The average concentrations of environmentally relevant constituents such as lead (0,18 mg?1), zinc (1,5 mg l?1), fluoride (10,6 mg l?1), and total cyanide (1.8 mg l?1) in the pore waters were distinctly larger than the inspection value of the German Federal soil Protection Ordinance for the pathway soil-groundwater. Lead, zinc, and total cyanide concentrations in the pore waters were largely underestimated by the eluates, as these concentrations were 70 to 90% lower in the eluates compared to the pore waters.

Conclusion

In the case of landfilled blast-furnace sludge, eluates according to DIN 38414 part 4 (S 4) provide low concentrations which are unrealistic to forecast concentrations in the seepage water.     

Ansätze zur regionalen Quantifizierung von Methan aus Pflanzen

Background

Methane as a gas influencing our climate is of high importance according to the Kyoto-Protocol. The more precisely we can determine anthropogenic and biogenic sources, the more effective measures we can take to reduce the gas. Direct emission of methane from plants apparently contributes significantly to the total emission but has not been accounted for in emission balances until now.

Methods

A model was created to calculate methane emission for a short time period in regional resolution for Lower Austria and to relate the results to known literature.

Results and Discussion

First model results suggest that the amount of methane released from plants in relation to emissions from other known sources are of importance.

Perspectives

The uncertainties associated with both measurements and quantification require reduction by further research.     

Auswahl repräsentativer Standorte zur Modellierung der Ausbreitung von gentechnisch veränderten Pflanzen in Nord-Deutschland

Goal and Scope

The use of genetically modified plants (GMP) in agriculture is increasing rapidly. While GMP in North and South America are already established an extensive cultivation in Germany is yet to come. Risk assessment on possible effects of released GMP are mainly based on empirical studies with a small spatial extent (laboratories, small-scale field trials). The joint research project ‘Generic detection and extrapolation of genetically modified rape (GenEERA)’ aimed at estimating the dispersal and persistence of genetically modified oilseed rape (Brassica napus) by the use of individual based models. The objective of the article at hand is to give a detailed account of the spatial variability of climate in Northern Germany (German Federal States of Brandenburg, Lower Saxony and Bremen Mecklenburg Western Pomerania, Schleswig-Holstein and Hamburg). Based on this, a method was developed that includes both, the determination of representative oilseed rapefields for modelling the dispersal of GM oilseed rape at field scale, and the subsequent generalisation of the results to landscapes.

Data and Methods

The statistically founded selection of modelling sites was performed by a compilation of available indicators within a GIS environment which are supposed to be important for the dispersal and the persistence of oilseed rape. Meteorological data on precipitation (P), air temperature (T), and sunshine duration (S) collected at up to 1,200 monitoring sites from 1961–1990 were as well as data on wind conditions (W) aggregated multivariate-statistically by Ward cluster analysis. An ecoregionalisation was used for characterising Northern Germany ecologically. Phenological data on the start of the oil seed rape bloom differentiated in the monitoring periods 1961–1990 and 1991–1999, respectively, were regionalised by performing variogram analysis and kriging interpolation. These maps were used to select appropriate Landsat images to identify rape fields by remote sensing algorithms as well as to define the respective flowering periods for individual based modelling.

Results

The separately generated P-T-S-W-Cluster were aggregated to four homogenic climatic regions. In combination with agricultural clusters defining typical landuse patterns (crop rotation, cultivation management) eight model regions were derived which describe the climatic and agronomic variations in Northern Germany. For each of these regions a representative monitoring site was selected serving for individual based modelling. At last, the modelling results were extrapolated back to the model regions applying corresponding GIS queries.

Discussion

The generated climatic regions reflect the transition of marine climate at the North Sea to continental climate in Northeast Germany. The shift in flowering of oil seed rape coincides with other studies on phenological changes of agricultural crops and wild plants.

Conclusions

Due to the huge calculation efforts and the lack of adequate land registers it was not possible to simulate the potential dispersal of GM oil seed rape at farm scale. Thus, generalisations were used to describe the variations of relevant ecological drivers affecting the dispersal of GMP. It could be shown that the aggregation of those factors to homogenic climatic regions was a successful approximation.

Recommendations and Perspectives

Due to the limited empirical data base it is necessary to validate and substantiate the modelling results by a GMP monitoring. The EU Directive 2001/18/EC on the deliberate release of genetically modified organisms into the environment stipulates assessment of direct and indirect effects of GMP on humans and the environment by case-specific monitoring and general surveillance. It should be realised as soon as possible, since the release and the cultivation of GMP in Germany have been started, already. The monitoring should be complemented by the implementation of a web-based geoinformation system (WebGIS) which enables access to relevant geodata and monitoring data and assists in analysing possible GMP impacts.     

Schnelle vor-ort-analytik zur untersuchung von rüstungsaltlasten

Field screening methods for the analysis of explosives (for which commercial test kits are generally available) are reviewed. These techniques include immunoassays, photometric methods, bio and chemical sensors as well as thin layer chromatography. Basic aspects of these techniques are discussed, their validation is presented and their application to water and soil samples from hazardous ammunition waste is described. An evaluation of field studies with commercial test kits demonstrates that these techniques can be applied successfully for both the exploration of suspected contaminated sites and their sanitation. These methods are used on-site. In general, they allow short analysis times and a high sample throughput, thus leading to a significant reduction of the number of samples to be analysed in the laboratory and the costs.     

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.     

Beurteilung des Ozonrisikos für die Waldregionen Bayerns am Beispiel des Jahres 2002 und des Extremtrockenjahres 2003 auf der Basis der externen Ozonexposition und der internen Ozonaufnahme

Background, aim, and scope Increasing background concentrations of ground-level tropospheric ozone and more frequent and prolonged summer drought incidences due to climate change are supposed to increase the stress on Bavarian forests. For such scenarios growth reduction and yield losses are predicted. Sustainable forest management in Bavaria aims to significantly increase the proportion of beech (Fagus sylvatica L.) because of its broad ecological amplitude. In our regional study different approaches for calculating ozone impact were used to estimate the risks for Bavarian forests in the average climatic, rather moist year 2002 and the extremely dry year 2003.Materials and methods Measurements were conducted for eleven forest ecosystem sites and two forest research sites representing typical Bavarian forest stands under different climatic conditions and situated in different altitudes. For risk assessment currently used approaches were applied either based on the calculation of the cumulative ozone exposure (external dose; MPOC maximal permitted ozone concentration; critical level AOT40_phen? accumulated ozone exposure over a threshold of 40 nl [O₃] l^–1, for the effective phenolgy of beech) or based on the calculation of the phytomedically relevant ozone flux into the stomata (internal dose, critical level AF_st>1,6, accumulated stomatal flux above a flux threshold of 1.6 nmol O₃?m^–2 PLA; PLA = projected leaf area). For calculations continuously recorded ozone concentrations and meteorological and phenological data from nearby rural open field background measuring stations from the national air pollution control and from forested sites were used. Additionally ozone induced leaf symptoms were assessed.Results The exposure-based indices AOT40_phen and MPOC as well as the flux-based index AF_st>1.6suggest that Bavarian forests are at risk from O₃ during a rather moist average year concerning climate conditions (2002) as well as in an extreme dry year (2003). Thus, growth reductions of 5?% are predicted when thresholds are exceeded. Threshold exceedance occurred in both years at all plots, mostly already at the beginning of the growing season and often even many times over. Ozone induced leaf symptoms could be detected only on a few plots in a very slight occurrence.Discussion The results for the applied critical level indices differed depending on climatic conditions during the growing seasons: Regarding exposure-based indices, the highest degree of threshold exceedance occurred in the dry year of 2003 at all plots; the flux-based approach indicated the highest stomatal ozone uptake and thus an increased risk at moist sites or during humid years, whereas the risk was decreasing at dry sites with prolonged water limitation. Hence, soil and accordingly plant water availability was the decisive factor for the flux-modelled internal ozone uptake via stomata. Drought and increased ozone impact can generate synergistic, but also antagonistic effects for forest trees. At water limited rather dry forest sites restricted transpiration and thus production, but concurrently lower ozone uptake and reduced risk for damage can be expected.Conclusions, recommendations, and perspectives For realistic site-specific risk assessment in forest stands the determination of the internal ozone dose via modeling flux based internal stomatal ozone uptake is more appropriate than the calculation of the external ozone dose. The predicted 5?% growth reductions are in discrepancy with the frequently observed increment increase during the last decades in forest stands. Comprehensive and significant statistical verification for ozone induced forest growth reduction as well as the systematic validation of thresholds for ozone in the field is still lacking. However, a multiplicity of different specific new and retrospective growth analysis data should allow closing the gap. Moreover, the determination of canopy transpiration with sap flow measurements is a novel approach to provide cause-effect related, site specific results for the effective internal ozone dose as well as for canopy water supply and consecutively for regional risk estimation. A further future objective is the refinement of O₃ flux modelling by further consideration of soil/water budget characteristics and the above mentioned improved estimations of crown and canopy transpiration. Further, the introduction of threshold ranges for forest trees in view of their specific regional climatic conditions and their validation in real forest stands is necessary for developing meaningful ozone risk predictions for forests.