Charakterisierung von Mückenbrutplätzen im Roßlauer Oberluch

Das Roßlauer Oberluch bietet mit seinen Feuchtflächen ideale Lebensräume für eine artenreiche Fauna und Flora. Auch Stechmücken finden hier gute Reproduktionsbedingungen. Auf Grund der prognostizierten Klimaerwärmung könnten sich diese Bedingungen sogar noch verbessern, denn starke Regenfälle, Überschwemmungen und hohe Temperaturen begünstigen die Fortpflanzung von Stechmücken. Neben den Faktoren, die die Entwicklung der Mücken fördern, wirken natürlich auch regulierende Mechanismen. Neben Fressfeinden spielen Nahrungskonkurrenten eine wichtige Rolle für den Bestand einer Art. Während die Fressfeinde bereits gut untersucht sind, ist über die Nahrungskonkurrenten der Mückenlarven bislang wenig bekannt. Mückenlarven filtrieren organische Partikel aus dem Wasser und beanspruchen demnach dieselben Nahrungsressourcen wie filtrierende Kleinkrebse, sodass Kleinkrebse ernstzunehmende Nahrungskonkurrenten für Mückenlarven sind. 2007 wurde im Rahmen komplexer Untersuchungen im Zusammenhang mit der Deichrückverlegung eine Studie zur Charakterisierung von Mückenbrutplätzen im Roßlauer Oberluch durchgeführt. Die Ergebnisse werden im Folgenden dargestellt

Deichrückverlegungen in Sachsen-Anhalt und wissenschaftliche Begleituntersuchungen am Beispiel des Roßlauer Oberluchs

Deichbau und andere flussbautechnische Maßnahmen haben dazu geführt, dass die Mittlere Elbe ihre ursprünglichen Überschwemmungsgebiete verloren hat. Um die Auswirkungen der alljährlich auftretenden Hochwasserereignisse einzudämmen, wurden große Bereiche der Talniederung durch Deiche vom Überflutungsgeschehen abgetrennt. Diese Eingriffe in den Naturhaushalt ermöglichten gleichfalls eine intensive ackerbauliche Nutzung oder eine hochwassersichere Bebauung der Auen. Die natürliche Auendynamik ist heute weitestgehend auf einen schmalen Bereich entlang der Elbe beschränkt. Hinter den Deichen sind die für die Elbeauen typischen Lebensräume von der lebenswichtigen Auendynamik abgeschnitten. Angepasste Auenarten und -lebensgemeinschaften treten zugunsten von Allerweltsarten zurück. Eine Wiederanbindung von Altauenbereichen an das Überflutungsgeschehen ist deshalb eine der vordringlichsten Maßnahmen zur Revitalisierung gefährdeter Auenlebensräume und stellt eine Chance dar, einen nachhaltigen und modernen Hochwasserschutz mit Naturschutzzielen zu verbinden. An der Elbe entspricht das aktuelle Hochwasserschutzsystem nicht den heutigen Anforderungen an den Hochwasserschutz. Um jedoch jederzeit auf mögliche große Hochwasserereignisse reagieren zu können, entstanden Anfang der 1990er Jahre in den Anliegerländern der Elbe zahlreiche Pläne für Deichrückverlegungen

Scientific Opinion about the Guidance of the Chemical Regulation Directorate (UK) on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessments

Abstract The EFSA Panel on Plant Protection Products and their Residues reviewed the guidance on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessment. The inclusion of aged sorption is a higher tier in the groundwater leaching assessment. The Panel based its review on a test with three substances taken from a data set provided by the European Crop Protection Association. Particular points of attention were the quality of the data provided, the proposed fitting procedure of aged sorption experiments and the proposed method for combining results obtained from aged sorption studies and lower‐tier studies on degradation and adsorption. Aged sorption was a relevant process in all cases studied. The test revealed that the guidance could generally be well applied and resulted in robust and plausible results. The Panel considers the guidance suitable for use in the groundwater leaching assessment after the recommendations in this Scientific Opinion have been implemented, with the exception of the use of field data to derive aged sorption parameters. The Panel noted that the draft guidance could only be used by experienced users because there is no software tool that fully supports the work flow in the guidance document. It is therefore recommended that a user‐friendly software tool be developed. Aged sorption lowered the predicted concentration in groundwater. However, because aged sorption experiments may be conducted in different soils than lower‐tier degradation and adsorption experiments, it cannot be guaranteed that the higher tier predicts lower concentrations than the lower tier, while lower tiers should be more conservative than higher tiers. To mitigate this problem, the Panel recommends using all available higher‐ and lower‐tier data in the leaching assessment. The Panel further recommends that aged sorption parameters for metabolites be derived only from metabolite‐dosed studies. The formation fraction can be derived from parent‐dosed degradation studies, provided that the parent and metabolite are fitted with the best‐fit model, which is the double first‐order in parallel model in the case of aged sorption

Investigation into experimental toxicological properties of plant protection products having a potential link to Parkinson's disease and childhood leukaemia

In 2013, EFSA published a literature review on epidemiological studies linking exposure to pesticides and human health outcome. As a follow up, the EFSA Panel on Plant Protection Products and their residues (PPR Panel) was requested to investigate the plausible involvement of pesticide exposure as a risk factor for Parkinson's disease (PD) and childhood leukaemia (CHL). A systematic literature review on PD and CHL and mode of actions for pesticides was published by EFSA in 2016 and used as background documentation. The Panel used the Adverse Outcome Pathway (AOP) conceptual framework to define the biological plausibility in relation to epidemiological studies by means of identification of specific symptoms of the diseases as AO. The AOP combines multiple information and provides knowledge of biological pathways, highlights species differences and similarities, identifies research needs and supports regulatory decisions. In this context, the AOP approach could help in organising the available experimental knowledge to assess biological plausibility by describing the link between a molecular initiating event (MIE) and the AO through a series of biologically plausible and essential key events (KEs). As the AOP is chemically agnostic, tool chemical compounds were selected to empirically support the response and temporal concordance of the key event relationships (KERs). Three qualitative and one putative AOP were developed by the Panel using the results obtained. The Panel supports the use of the AOP framework to scientifically and transparently explore the biological plausibility of the association between pesticide exposure and human health outcomes, identify data gaps, define a tailored testing strategy and suggests an AOP’s informed Integrated Approach for Testing and Assessment (IATA)

Guidance on tiered risk assessment for plant protection products for aquatic organisms in edge-of-field surface waters

EFSA’s Panel on Plant Protection Products and their Residues (PPR) was tasked to revise the Guidance Document (GD) on Aquatic Ecotoxicology under Council Directive 91/414/EEC (SANCO/3268/2001 rev.4 (final), 17 October 2002). This Guidance of the PPR Panel is the first of three requested deliverables within this mandate. It has its focus on tiered acute and chronic effect assessment schemes with detailed guidance on tier 1 and higher tier effect assessments for aquatic organisms in edge-of-field surface waters and on proposals regarding how to link effects to exposure estimates. The exposure assessment methodology was not reviewed and it is assumed that the current FOCUS surface water exposure assessment methodology will continue to be used for exposure assessment at EU level. The current GD is intended to be used for authorisation of active substances at EU level as well as for plant protection products at Member State level. The effect assessment schemes in this GD allow for the derivation of regulatory acceptable concentrations (RACs) on the basis of two options: (1) the ecological threshold option (ETO), accepting negligible population effects only, and (2) the ecological recovery option (ERO), accepting some population-level effects if ecological recovery takes place within an acceptable time period. In the tiered effect assessment schemes, in principle, all tiers (1, 2 and 3) are able to address the ETO, while the model ecosystem approach (tier 3), under certain conditions, is able to also address the ERO. The GD provides the scientific background for the risk assessment to aquatic organisms in edge-of-field surface waters and is structured to give detailed guidance on all assessment steps. An executive summary joining all parts of the guidance and decision schemes in a concise way is provided and is intended to help applicants and regulatory authorities in day-to-day use

Mechanistic effect modeling of earthworms in the context of pesticide risk assessment: Synthesis of the FORESEE Workshop.

Earthworms are important ecosystem engineers, and assessment of the risk of plant protection products towards them is part of the European environmental risk assessment (ERA). In the current ERA scheme, exposure and effects are represented simplistically and are not well integrated, resulting in uncertainty when applying the results to ecosystems. Modeling offers a powerful tool to integrate the effects observed in lower tier laboratory studies with the environmental conditions under which exposure is expected in the field. This paper provides a summary of the FORESEE Workshop ((In)Field Organism Risk modEling by coupling Soil Exposure and Effect) held January 28‐30, 2020 in Düsseldorf, Germany. This workshop focussed on toxicokinetic‐toxicodynamic (TKTD) and population modeling of earthworms in the context of environmental risk assessment. The goal was to bring together scientists from different stakeholder groups to discuss the current state of soil invertebrate modeling, explore how earthworm modeling could be applied to risk assessments, and in particular how the different model outputs can be used in the tiered ERA approach. In support of these goals, the workshop aimed at addressing the requirements and concerns of the different stakeholder groups to support further model development. The modeling approach included four submodules to cover the most relevant processes for earthworm risk assessment: Environment, Behavior (feeding, vertical movement), TKTD, and Population. Four workgroups examined different aspects of the model with relevance for: Risk assessment, earthworm ecology, uptake routes, and cross‐species extrapolation and model testing. Here, we present the perspectives of each workgroup and highlight how the collaborative effort of participants from multidisciplinary backgrounds helped to establish common ground. In addition, we provide a list of recommendations for how earthworm TKTD modeling could address some of the uncertainties in current risk assessments for plant protection products

Bioaccumulation metallique et metallothioneines chez trois especes de poissons provenant du littoral Nord-Pas-de-Calais

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : TD 84069 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Sub-lethal effects of metal exposure: Physiological and behavioural responses of the estuarine bivalve Macoma balthica

Variation in glycogen concentration, condition index (CI) and filtration activity were measured in the bivalve Macoma balthica buried in sediment and experimentally exposed to cadmium (Cd). The stress due to elevated but sub-lethal concentrations (300 ppb Cd) affected the overall fitness of the organism as all parameters monitored responded significantly. Lower concentrations tested (10, 30 and 100 ppb) only induced a significant decrease in filtration activity, which may play a protective role, enabling the organism to slow down its metabolic activity and preserving the integrity of its reserves (reflected by stable CI and glycogen levels). Hence, the various endpoints selected show different thresholds. Our results also demonstrate that under high exposure, small individuals loose proportionally more glycogen per unit of weight than larger ones, thus confirming the higher sensitivity of small individuals to metal contamination. Furthermore, exposure to intermediate concentration (30 ppb) seems to be beneficial to the small individuals as indicated by their high CI values compared to the control. These results showed thus that non-sigmoidal concentration-response relationship and sizes of individuals should be considered in monitoring programmes and risk assessment. © 2004 Elsevier Ltd. All rights reserved