9 research outputs found
The influence of insecticide exposure and environmental stimuli on the movement behaviour and dispersal of a freshwater isopod
Derivation of predicted no-effect concentrations for lindane, 3,4-dichloroaniline, atrazine, and copper
Environmental risk assessment is a key feature of regulations controlling the placing of new, and the maintenance of existing, chemicals products in the market place. For example, European Commission Directive 93/67/EC on Risk Assessment for New Notified Substances and Commission Regulation (EC) No. 1488/94 on Risk Assessment for Existing Substances requires that risk assessments be carried out for new and existing substances in the European Community. The process of environmental risk assessment seeks to determine the balance of probability of species and communities being damaged by chemical releases. The process relies upon a valid estimation of a predicted environmental concentration (PEC) in relevant environmental compartments and a predicted no effect concentration (PNEC) below which the organisms present in that compartment are unlikely to be significantly affected. If the PEC exceeds the PNEC there is a potential for damaging effects to occur. This article focuses on the determination of PNECs for risk assessment. Methods for determining a PNEC described in OECD Monograph 26 (1989, Report of the OECD Workshop on Ecological Effect Assessment, Paris, France, have been applied to data derived for the four chemicals lindane, 3,4-dichloroaniline, atrazine, and copper in a series of collaborative research projects funded by the European Commission
The development of toxicity tests for freshwater pollutants and their validation in stream and pond mesocosms
The number and variety of freshwater species and bioassay procedures currently recommended in European Directives for assessing the risk posed by pollutants to freshwater ecosystems is rather limited. The aim of the three consecutive European Commission-sponsored programmes described here was to modify or develop new laboratory methods that could be used for evaluating toxicity to freshwater species and which would be suitable for incorporation into the current "notification scheme" for new substances. An essential phase of each project was a validation process in which results of laboratory tests were compared with values obtained in the field using structural and functional responses of communities. The laboratory tests were developed by Fraunhofer-Institut für Umweltchemie und Ökotoxikologie (FhG) Potsdam-Rehbrücke with algae, protozoa and a variety of in vitro cellular/subcellular preparations; by the State University of Ghent with water column invertebrates, and by Cardiff University with benthic invertebrates. The laboratory tests included in vitro procedures, conventional whole organism single species tests, simple multi-species systems and microcosms. The field validation was carried out by Shell Research Sittingbourne employing artificial streams and by FhG Schmallenberg and GSF-Forschungszentrum für Umwelt und Gesundheit, Munich with artificial ponds and included single species responses but also structural and functional community responses. The same reference chemicals: lindane, copper, 3,4-dichloroaniline and atrazine were used by all laboratories. A comparison of the most sensitive toxicity response determined for each reference chemical using the laboratory toxicity tests, with that determined by the field simulation procedures revealed that for the reference chemicals lindane, copper and atrazine, adverse effects were not detected either for single organisms or for structural and functional characteristics of the community or ecosystem, at concentrations below those identified in the laboratory toxicity tests. In the case of dichloroaniline, however, effects on the population dynamics of one species in the pond mesocosm were recorded at a concentration ×16 below that reported in the laboratory. We conclude that appropriately designed, relatively simple and inexpensive laboratory toxicity tests with a selection of test species are generally adequate, with small application factors, for predicting the environmental risk of polluting chemicals to freshwater ecosystems
Variability in feeding of Gammarus pulex: moving towards a more standardised feeding assay
Feeding behavioural studies with Freshwater Gammarus spp.: The importance of a standardised methodology
Freshwater Gammarids are common leaf-shredding detritivores, and they usually feed on naturally conditioned organic material, in other words leaf litter that is characterised by an increased palatability, due to the action and presence of microorganisms (Chaumot et al. 2015; Cummins 1974: Maltby et al. 2002). Gammarus spp. are biologically omnivorous organisms, so they are involved in shredding leaf litter and are also prone to cannibalism, predation behaviour (Kelly et al. 2002) and coprophagy when juveniles (McCahon and Pascoe 1988). Gammarus spp. is a keystone species (Woodward et al. 2008), and it plays an important role in the decomposition of organic matter (Alonso et al. 2009; Bundschuh et al. 2013) and is also a noteworthy prey for fish and birds (Andrén and Eriksson Wiklund 2013; Blarer and Burkhardt-Holm 2016). Gammarids are considered to be fairly sensitive to different contaminants (Ashauer et al. 2010; Bloor et al. 2005; Felten et al. 2008a; Lahive et al. 2015; Kunz et al. 2010); in fact Amphipods have been reported to be one of the most sensitive orders to metals and organic compounds (Wogram and Liess 2001), which makes them representative test organisms for ecotoxicological studies and valid sentinel species for assessing water quality status (Garcia-Galan et al. 2017)