SETAC Globe - Environmental Quality Through Science
 
  6 October 2011
Volume 12 Issue 10
 

Return to the Globe

More from Milan

Click to expand/collapse

  • Sorption and bioavailability of Organic Chemicals: Mechanisms Relevant for Toxicity and Bioremediation
    • John Parsons (University of Amsterdam, the Netherlands) and Jose Julio Ortega Calvo (Institute for Natural Resources and Agrobiology, Seville, Spain)

      We need, for sustainable environmental quality, to understand the effects of soil and sediment pollution and to remediate polluted soils and sediments. The bioavailability of organic chemicals continues to be an important issue in the assessment of their environmental risks and the development of bioremediation strategies. While much progress has been made over recent years in understanding sorption mechanism of nonpolar compounds and their influence on bioavailability, little progress has been made in developing approaches to increase the bioavailability where this is required for successful remediation. Furthermore, the mechanisms that are important for ionic and polar compounds are still poorly understood, despite encouraging recent progress. The aim of this session was to bring together recent work on the sorption and bioavailability of ionic, polar and nonpolar organic chemicals in order to provide a comprehensive overview of the new developments in understanding important mechanisms for these chemicals and their role in determining bioremediation approaches. Presentations describing biological influences on toxicity and biodegradation of sorbed chemicals were also encouraged.

      Presentations in this interesting session covered a number of issues such as the effects of black carbon amendment on the bioavailability of PAHs and the mechanisms of sorption of ionic compounds. Black carbon was a topic in three of the oral presentations and several posters. There is a great deal of interest in the amendment of contaminated soil and sediment with activated carbon to reduce toxicity but there is some concern about its effect on biodegradation of the contaminants. The presentation of Geoffrey Marchal was particularly interesting in this respect showing that black carbon does not prevent biodegradation of phenanthrene. On a related note, the poster of Eleonora Conglui showed that microbial biosurfactants can enhance the desorption of PAHs from soil organic matter and including biochar. The sorption of anionic compounds by black carbon was the topic of the presentation of Joe Pignatello in which he presented evidence for the involvement of a novel mechanism involving ionization of water and release of hydroxide into solution. The sorption of organic cations was addressed in Steven Droge's presentation in which he made the case for the application of multi-parameter models to describe the complex sorption of these molecules to organic matter. On the methodological side, highlights were applications of passive sampling and microbial bioreporters to measure bioavailable contaminants and the very interesting use of fungi as a system to deliver bacteria to poorly accessible contaminants in soil. As a whole, the session demonstrated that mechanistic approaches can give important insights into the factors limiting the bioavailability of organic chemicals in soils and sediments and methods that can enhance bioavailability when this is required for remediation.

      Author contact information: J.R.Parsons@uva.nl
  • Biodegradation and Bioremediation of Organic Pollutants
    • Gary Bending (University of Warwick, UK)

      For most organic pollutants, biodegradation is the primary process determining fate and persistence in the environment and within bioremediation systems. Understanding microbial processes underlying biodegradation provides opportunities to improve prediction and management of pollutants in the environment. Additionally, improved understanding of key processes determining biodegradation of pollutants allows us to improve the environmental realism of lab biodegradation testing systems.

      Rates of biodegradation are governed by a number of microbial characteristics and interactions, including community diversity and catabolic potential, adaptation processes within communities that induce catabolism, and the immigration, establishment and survival of degraders. Furthermore the effectiveness of degraders is determined by bioavailability, which is governed by the physico-chemical environment and the properties of the compound itself. There have been enormous advances in methods to investigate the diversity and functioning of microbial communities involved in biodegradation, which are providing new opportunities to predict and manage pollutant biodegradation. This session focused on the microbiology of pollutant biodegradation, integrating understanding from terrestrial and aquatic systems, including man-made bioremediation systems. Russell Davenport (Newcastle University UK) showed how an understanding of variations in bacterial diversity within and between environmental compartments can be used to gain a better understanding of the biodegradation of chemicals, particularly applied to regulatory testing regimes, and how a probabilistic assessment can be used to estimate and compare the likelihood of biodegradation. He outlined how new methods of deep sequencing will advance our knowledge in this area. Tim Martin (Brixham/ Newcastle) showed how cell concentration methods for preparing inocula for biodegradation tests can bias microbial community composition compared to original samples. He outlined how test volume as well as inocula density can affect variability in replicate biodegradation tests. His work demonstrated the utility of enhanced testing using more environmentally-relevant concentrations can lead to more reliable biodegradation outcomes. Agnieszka Kowalczyk (Warwick University UK) showed how functional gene markers can be used to target specific microbial communities driving degradation in the environment, particularly demonstrating how degradation of pollutants can be driven by diverse communities. She also showed that by careful targeting of catabolic pathways, it was possible to develop a single functional marker that could be used to characterise communities involved in the degradation of diverse organic pollutants; this could be a really powerful tool to advance understanding of degradation in diverse situations. Lawrence Davies (Warwick University) showed that phototrophs at the soil surface are a previously unrecognised driver of degradation at the soil surface―inclusion of this pathway in regulatory testing regimes could help bridge the gap between laboratory and field systems. Emma Butler (Cranfield University) showed that the transformation of triclosan to methyl-triclosan is a more important pathway than previously thought in soil amended with sludge. John Parsons's (Amsterdam University) work focused on the hypothesis that a mechanism for defluoro-respiration was thermodynamically feasible using perfluorinated organic acids and set about demonstrating that existing dechloro-respiring bacteria could perform some degradation of the parent compound.

      Author contact information: gary.bending@warwick.ac.uk
  • Fate and Exposure Modelling including Scenario Analysis
    • Antonio Di Guardo (University of Insubria, Como, Italy) and Matthew MacLeod (Stockholm University, Sweden)

      Models are indispensable tools in any proper evaluation and management strategy for chemical risk assessment. This session was a contribution of the SETAC Exposure Modeling Advisory Group and invited contributions describing studies of model development and use in environmental fate and exposure studies. Industrial chemicals, pesticides and legacy pollutants were all included.

      The modeling session was well-attended by between 100 and 150 people on Wednesday morning. We had 12 platform presentations and more than 30 posters. The platform session started with three presentations describing scenario definitions in regulatory modeling of pesticides in the European context. We also heard about modeling of herbicides released in rice cultivation in Japan using a highly spatially and temporally resolved multimedia fate model. In the field of persistent organic chemicals we heard presentations about the possible impacts of future changes in environmental conditions that will result from climate change on the large-scale distribution of POPs, especially with respect to transport to and exposure in the Arctic.

      Two presentations dealt with modeling spatial and temporal variability in POPs concentrations at different spatial scales. One presentation described general phenomena that determined variability in concentrations in the atmosphere by integrating physical and chemo-dynamic models. The other examined POPs in the North Sea in detail. Ecosystem and human exposure to chemicals was described in studies of bioaccumulation and risk arising from PCBs in sediments, a screening study of indirect exposure of humans to contaminants in personal-care products, and a study examining the factors that determine trends in biomonitoring data for POPs. Finally, a proposal to develop "good modeling practice" guidelines was presented on behalf of SETAC's Exposure Modeling Advisory Group.

      Author contact information: antonio.diguardo@uninsubria.it; matthew.macleod@itm.su.se
  • (Non-)Extractability and Bioavailability of Organic Chemicals in Relation to Analytical and Regulatory Issues
    • Andreas Schaeffer(RWTH Aachen University, German), Andreas Focks (Wageningen UR, the Netherlands), and Andreas Hoellrigl-Rosta (the Federal Environment Agency, Dessau, Germany)

      The purpose of this session was to enhance the understanding of bioavailability dynamics and mechanisms and to explore the potential of introducing bioavailability as a concept in the prospective risk assessment for chemicals. The availability of organic contaminants like pesticides, pharmaceuticals or ingredients from personal care products in soils and sediments drives possible adverse effects on biota from the microorganism up to the mammalian level. In principle, the availability of a chemical differs considerably with respect to the biotic end-point under study. As an alternative to the elaborate task to differentiate the bioavailability of a chemical for different traits of biota, physico-chemical extraction methods can be applied to estimate the availability kinetics of a chemical in soil and sediment. Methods to extract chemicals from soil or sediment range from mild methods using, for example, aqueous calcium chloride or methanol to harsh methods that use additional energy to support extraction such as elevated temperature and pressure or microwaves. The bioavailable fraction of a chemical is thought to be related to the amount that can be extracted from soil or sediment without destroying or changing the respective matrix, hence extracts from harsh methods do not yield the typical bioavailable fraction of a substance from soil. However, there is increasing evidence that parent compound and known metabolites are still extractable from a residual pool in soil with such harsh methods after pre-extraction with mild, non-destructive solvents.

      The need for bioavailability considerations in regulatory risk assessment arises typically for more persistent compounds with a tendency to form non-extractable residues (NER) in environmental matrices such as pesticides or pharmaceuticals. For such substances, current regulatory risk assessment procedures have to be reconsidered, because the calculation of half-life times, TER or PEC/PNEC ratios may be not on a par with current scientific knowledge.

      Session contributions linked the aspects of bioavailability of pollutants to the extractability and non-extractability of residues in soils and sediments. Studies elucidating the nature of NER with respect to binding mechanisms and structural aspects as well as the influence of environmental driving forces such as temperature, microbial activity or humidity were also featured in this the session. Experimental or theoretical approaches that focused on the mid- and long-term availability of NER and respective consequences for regulatory risk assessment were equally welcome. Also, reports on the fate of xenobiotics using sequential extraction methods were invited to this session, as well as studies that relate effect experiments to bioavailable concentrations of a chemical.

      Key messages from selected presentations are summarized below:
      1. Höllrigl–Rosta et al.: NER is composed of Hidden Hazard (type-1 NER) : potential for accumulation and remobilization; Safe Sink (type-2 NER): no potential for remobilisation (covalently bound or biogenic residues) Assume type-1 unless type-2 is proved.
      2. Trapp et al.: Conceptual modeling distinguishes between reversibly sequestered residues, biotic and abiotic NER and enables determination of rate constants for the respective processes.
      3. Kästner et al.: NER may consist of considerable amounts of biogenic residues (safe sink)
      4. Gulkowska et al.: NER may consist to considerable parts of covalently bound substance(safe sink). Covalent bonding is promoted in the presence of oxidative enzymes and inorganic oxidants
      5. Müller et al.: NER may contain considerable parts of reversibly sorbed residues, partially very rapidly formed (hidden hazard)
      6. Jablonowski et al.: After years of incubation, aged pesticide residues may consist of considerable parts of parent compound (hidden hazard).
      Author contact information: andreas.focks@wur.nl
  • Assessing the Exposure, Effects and Risks of Pharmaceuticals and Personal Care Products (PPCPs) in the Environment
    • Bryan Brooks (Baylor University, Waco, Texas, USA), Tom Hutchinson (CEFAS, Dorset, UK), Joakim Larsson (Sahlgrenska Academy at the University of Gothenburg, Sweden), and Jim Lazorchak (Environmental Protection Agency, Cincinnati, OH, USA)

      There have been many studies published on the occurrence of pharmaceuticals and personal care products (PPCPs) in the environment as well as laboratory studies on their effects on aquatic and terrestrial organisms. Only a few studies, however, have been published thus far on the direct linkage of exposure and effects of PPCPs to wildlife. The purpose of this session was devoted to address the prioritization, characterization and hazard assessment approaches and exposure and effects of PPCPs on aquatic and terrestrial organisms.

      Overall the objectives and expectations of the session were met, if not exceeded. One particular observation was that many of the laboratory studies and mesocosm studies have moved to assessing environmental concentrations. Many of the presentations have shown that some PPCPs in the environment at current concentrations result in responses by and effects on aquatic and terrestrial life. For example, novel findings were reported for understudied organisms (e.g., mussels, crabs, frogs) and compounds with relatively limited information. However, there is still a lack of empirical data on effects for the majority of PPCPs that follow an a priori Adverse Outcome Pathways (AOP) approach, which attempts to support hypothesis development and effects assessment by connecting potential molecular initiation events through adverse effects at the individual and population levels of biological organization. It is now time to use these end points and indicators derived from laboratory studies in field studies so that eco-epidemiological analyses can be conducted to see if PPCPs are impacting real world communities.

      Several novel approaches were presented such as looking at the impact of PPCPs (e.g., triclosan) on ecosystems services as provided by biofilms in river sediments. Antibiotic and antimicrobials may pose additional risks to the environment beyond antibiotic resistance; bacteria are important components of ecosystems and are probable targets of for this class of PPCPs.

      Author contact information: joakim.larsson@fysiologi.gu.se; bryan_brooks@baylor.edu; tom.hutchinson@cefas.co.uk; lazorchak.jim@epamail.epa.gov
  • New Approaches in the Simulation of Realistic Multistress and Multispecies Scenarios
    • Silvia Mohr (Federal Environment Agency, Berlin, Germany) and Almut Gerhardt (LimCo International GmbH, Konstanz, Germany).

      Traditional risk assessment approaches based on single species toxicity tests and exposure to single substances at constant concentrations do not reflect relevant ecological processes. Realistic environmental scenarios should consider complex communities exposed to complex mixtures of changing composition and concentration. Such considerations are need to conduct more realistic risk assessments and reduce the uncertainties that come from extrapolating results from laboratory data.

      The presentations in this session demonstrated that there are various solutions to bridge the gaps between reductionist single species test approaches and reality. Approaches presented in our session included:
      1. new (non-standardised) endpoints (behaviour, immune)
      2. mixtures of toxic and «natural» stressors (abiotic)
      3. direct/indirect biotic effects, e.g. «trophic» ecotoxicology (predator/prey)
      4. mesocosm or in situ studies (effects on whole biocoenoses)
      5. adaptation, evolutionary ecotoxicology
      6. repeated pulse exposures and realistic concentrations combining experimental data with modelling
      The take-home message from these presentations was that the combination of different methods such as the use of biomarkers and physiological endpoints as well as the linkage of lab, field investigations, and modelling seem to be promising tools in getting closer to reality. Scientists should dare to include (instead of traditionally exclude) complexity in experiments study biotic (cascade) effects (> two species interactions).

      Author contact information: silvia.mohr@uba.de
  • Environmental Fate and Bioaccumulation of Organic Pollutants in Aquatic Systems
    • Rainer Lohmann (University of Rhode Island, USA) and Jordi Dachs (CSIC, Barcelona, Spain)

      Organic pollutants are subject to a variety of processes once released to marine or continental waters. The pollutants in question include not only legacy POPs, but also emerging organic pollutants such as polyfluorinated compounds, various (brominated, phosphate ester) flame-retardants, dechlorane plus, alkylphenols, synthetic polycyclic musk fragrances, pharmaceuticals and current-use pesticides. After their atmospheric deposition to the ocean or river watershed, or direct release to rivers, lakes or reservoirs, the pollutants are subject to a number of environmental processes such as degradation, settling, exchange with the atmosphere, advective transport, water-sediment recycling, sediment resuspension events, flooding, bioaccumulation, transport to groundwater, etc. These processes affect the pollutants' fate at various scales from local to regional scale. The environmental fate and impact will thus depend on these environmental processes and the chemical properties. With this session, we brought together groups working on organic pollutants in aquatic systems with contributions on the environmental processes, biogeochemical or physical, that control their concentrations, fate and bioaccumulation in trophic webs. The session featured scientists from different fields - environmental scientists measuring the distribution of established or emerging organic contaminants on local, regional or larger scales; biogeochemists with their intrinsic knowledge of relevant ecological processes at different scales; modelers reflecting the theoretical state of the art with their predictive capabilities and regulatory officials contributing to the understanding of the environmental fate to organic pollutants in aquatic systems. Contributions related to the interactions between cycling of organic pollutants in rivers and other aquatic ecosystems and their toxicological effects were also welcome.

      Session highlights are summarized, as follows. Galban-Malagon showed that several PAHs when deposited in the Mediterranean Sea were strongly degraded in the water column. This degradation is most likely biologically based on a combined activity of bacteria, phyto- and zooplankton, which have all been shown to be able to degrade PAHs. In contrast, chlorinated biphenyls were simply removed from the atmosphere to deeper waters. Other studies highlighted the ubiquity of a wide range of organic pollutants present in atmosphere and surface ocean of the northern hemisphere. For example, fluorotelomer alcohols were detected in the Greenland current with net deposition from the atmosphere. Results by Xie et al suggested that melting from the Greenland glacier might already be a source of these contaminants. Nizzetto et al. could show that the biological pump indeed affects the fate of organic pollutants in the water column of Lago Magiore. During a phytoplankton bloom, PCB dissolved concentrations in the water column decreased, causing a change in fugacity gradient towards net uptake of PCBs from the atmosphere. Once the bloom ceased, the gradient switched back to net volatilization.

      In the talks focusing on bioaccumulation, Ruedel et al. showed that recent efforts to regulate hexabromocyclododecane (HBCD) emissions worked rather well, with strong decreases for HBCD detected in fish across a wide range of European locations. Byer et al. presented data on the presence of organic contaminants in American eel, exploring whether these concentrations were high enough to potentially be the cause for the drastic decline in eels over the last few decades. A comparison with European eels showed the contemporary burden of American eel by dioxins and other contaminants to be below critical levels. The historical exposure of both eel however, was presumably higher and could have indeed been a primary cause of the observed decline. Numerous talks highlighted the versatility of passive samplers as useful tools to measure organic contaminants in the water.

      Author contact information: lohmann@gso.uri.edu; jordi.dachs@idaea.csic.es
  • Alternatives to Animal Testing in Ecotoxicology
    • Adam Lillicrap (NIVA, Oslo, Norway)

      Animal alternatives are becoming increasingly important in the field of ecotoxicology, not only in terms of ethical and economical perspectives, but also to increase the level of data that is generated for substances that need to be registered for regulatory purposes. Since the introduction of REACH, many chemicals require ecotoxicity testing using alternative approaches which maintain the fundamental premise of protection of the environment. One of the first animal alternative sessions at SETAC was held in 2005 when it was a relatively new concept for ecotoxicity testing. Since then it has grown and the scientific presence this year gives a clear indication on the importance of this topic. This year, the animal alternative session received more than 50 abstracts and over 20 of these were requests for platform presentation.

      The animal alternative session was divided into two parts, the first was focused on the practical applications that are being developed. It was clear that the research that is being performed on fish embryos and fish cell lines is fine tuning the excellent techniques that are already available and will hopefully strengthen the alternative approaches for testing chemicals with regards to REACH and other legislation. The second session focused on the animal alternative concept from a more holistic point of view and focused on the aspects that are of fundamental importance in obtaining regulatory acceptance of the alternative approaches that are being developed.

      Author contact information: ali@niva.no
  • Detecting, Quantifying and Characterizing Engineered Nanomaterials in the Environment and in Biological Systems
    • Edward Heithmar (U.S. Environmental Protection Agency), Karen Tiede (The Food and Environment Research Agency, UK), Frank von der Kammer (University of Vienna, Austria), and Samuel Legros (University of Vienna, Austria)

      Sustainable development of nanotechnology depends on understanding the environmental behavior and potential adverse effects of released engineered nanomaterials. Research into the environmental implications of nanotechnology is currently limited by a lack of methods for detecting, quantifying and characterizing nanomaterials in environmental compartments and exposed organisms. Some promising methodology tools have been developed to understand the environmental behavior, exposure, and toxicity for certain nanomaterials, especially in relatively simple systems. However, many gaps remain in our ability to track nanomaterials through the environment and to detect them in biota. This session was a forum for communicating the most recent advances in narrowing those gaps.

      Session highlights included:
      1. An array of approaches were presented: particle imaging by transmission and scanning electron microscopy (TEM, SEM), as well as wet SEM; electrochemical quantification; hyphenated size separation/element-selective detection such as field flow fractionation
      2. (FFF) interfaced with inductively coupled plasma mass spectrometry (ICPMS); spectroscopic approaches such as surface Raman; and single particle ICPMS as both a stand-alone screening method and coupled with FFF for more selective analysis.
      3. Nanoparticles at relatively high concentration (mg/L) in simple, controlled matrices such as toxicological test media can now often be adequately measured and characterized.
      4. Measurement and characterization of nanoparticles at concentrations more realistic for most environmental release scenarios is still extremely challenging. This is particularly important because predominant nanomaterial processes can be dramatically different at low concentration.
      5. Measurement and characterization of nanoparticles in more complex matrices such as soil, sediments or wastes represents another challenge. Studying those environmental compartments is nonetheless important because they are expected to be widely impact by the environmental release scenarios.
      6. For nanoparticles interacting with biological tissues, imaging techniques are usually the only practical approach, even with their well-known shortcomings.
      7. Rapid progress is being made in the detection, quantification, and characterization of engineered nanoparticles, but much work remains for low concentrations and more complex systems.
      Author contact information: heithmar.ed@epa.gov
  • Integrated Science: Key to Risk Assessment
    • Stefan Kools (Grontmij BV) and Christina Ruden (Department of Philosophy at the Royal Institute of Technology (KTH) in Stockholm)

      In this broad session scientists were challenged to give examples of risk assessments in which multiple disciplines were integrated, including human and environmental risk assessment. Presenters discussed several methods to evaluate polluted sites (using a Triad approach), sediment and water quality (Water Framework Directive), and evaluation of chemical data for risk assessment.

      The session highlighted that people in risk assessment are seeking ways to decide which data can be included. Examples came from different angles that showed that selection is done on a case-by-case basis. Interestingly, we didn't see a common way of evaluating the data input. The call for using a model-derived no-effect concentrations as opposed to no-observed effect concentrations or a lethal concentrations was adding some statistical input in the session and left food for thought. The most discussion was after the session on using non-standard data (Agerstrand), since this may push regulation to derive low safe levels for substances with specific modes of action (pharmaceuticals, including E2).

      Author contact information: stefan.kools@grontmij.nl
  • Impact and Remediation of Wastewater
    • Mirco Bundschuh (University of Koblenz, Landau, Germany)

      The session addressed issues regarding fate and effects of micropollutants in wastewaters by also considering advanced treatment methods. As wastewater treatment plant effluents are a major source of micropollutants, it is important to understand the fate of compounds, the formation of transformation products and their potential effects in the environment. Moreover, it is essential to assess the implication of advanced treatment processes, which are applied to reduce loads of micropollutants. However, the applied sampling procedure, which is usually related to the hydraulic retention time, may lead to an over- or underestimation of removal efficiencies during the wastewater treatment process. "Residence time distribution" may help to solve this problem. Finally, advanced treatment technologies like Fenton reaction, ozonation or activated carbon seem to reduce the ecotoxicity of industrial and municipal wastewaters, which was indicated by a broad range of bioassays (including macroinvertebrate community data). However, depending on the process used, toxic transformation products may be formed increasing toxicity, which can eventually be removed during sand filtration. Although the session highlighted the increasing knowledge in this research field, underlying processes are not totally understood stressing the need of further research regarding the impact and especially the remediation of wastewaters.

      Author contact information: bundschuh@uni-landau.de
  • Mechanistic Modeling for Risk assessment: Sub-lethal Responses and Population-level Effects
    • Virginie Ducrot (INRA, Rennes, France), Volker Grimm (Helmholtz Centre for Environmental Research, Leipzig, Germany) , and Sandrine Charles (University of Lyon, Villeurbanne, France)

      Mechanistic effect models are increasingly being considered as a major tool for ecological risk assessment of chemicals. Because they provide a way to bring information that cannot be obtained experimentally (like expected effects at the population level, integration of differences in exposures across space and time), and because they help to explain differences in toxicity between species, they adequately complement toxicity studies that form the basis of risk assessment procedures. Yet, such models have rarely been used in ecological risk assessment. The main reasons are: a lack of standards for communicating the models, a lack of guidance on model design and analysis, and insufficient number of case studies that demonstrate the added value of model-based risk assessments. Therefore, providing adequate information on when and how to use such models in practice is a major challenge. Thus, this session aimed at presenting current trends in meeting this challenge. The session was extremely well attended, indicating increasing interest in the topic within the SETAC community.

      The session provided insight on how ecological risk assessment will benefit from individual and population models. Documentation standards were presented to facilitate communication, amongst modelers, regulators and risk assessors.

      Several messages were delivered during the session:
      1. Stakeholders expect a lot from models but they ask for validation, better communication and guidance for good modeling practice
      2. "What is not understood will be ignored"
      3. A stepwise approach appears useful to link lab-based endpoints to protection goals
      4. Case studies demonstrated that risk quotient-based approaches can be misleading
      5. Density dependence may modulate toxicant effects at the population level
      6. Modeling allows extrapolating between different exposure patterns
      7. Modeling can be used to detect inconsistencies in data interpretation
      8. The TRACE documentation framework has been promoted to facilitate model-based risk assessment.
      Author contact information: virginie.ducrot@rennes.inra.fr
  • Assessment of the Effects of Veterinary Drugs on Dung and Soil Organisms
    • Joerg Roembke (ECT Oekotoxikologie GmbH, Floersheim, Germany) and Nicole Adler (Federal Environmental Agency, Dessau, Germany)

      Since the publication of the International Cooperation on Harmonisation of Technical Requirements for Registration of Veterinary Medicinal Products (VICH) guidelines (2000, 2005) and the European Medicines Agency (EMEA) Technical Guidance (2008), the effects of veterinary pharmaceuticals (VPs) (in particular parasiticides) on dung (beetles, flies) and soil (springtails, earthworms) organisms have regularly been addressed. Mainly based on the work of the SETAC Advisory Group Dung Organism Toxicity Testing Standardisation (DOTTS), respective Organisation for Economic Co-operation and Development (OECD) test guidelines with dung flies and dung beetles have been developed (published in 2008 and 2010). While the number of data obtained from standardised tests is increasing considerably, some issues in the area of risk assessment of veterinary drugs in dung and soil are still open. In a first step, the existing laboratory test guidelines can be methodologically improved (e.g., the dung beetle test lacks sublethal endpoints). Even more important, all existing test requirements just cover the laboratory level, but no guidance is available for higher-tier testing so far. Despite some progress in applying different multispecies, semi-field or field tests as part of the registration process of VPs, there are still no standard higher-tier tests available. Even more gaps do exist in the area of the evaluation and assessment of the results of such tests. In addition, the role of modelling in an emerging high-tier risk assessment of VPs in the terrestrial environment is unclear. One major aim of the session was to bringing together different methods for assessing the effects of VPs on dung and soil organisms on all levels of testing. In addition, contributions with an integrative view on VP risk assessment, especially those including the ecology of these organisms, were invited. Finally, the view of different stakeholder groups on how the legal and methodological framework of VP risk assessment will evolve was especially interesting for this session.

      Currently, methods and assessment schemes for Tier B testing of veterinary pharmaceuticals are being intensively discussed in the European Union. A detailed approach was presented by Adler et al. Not yet adapted for regulatory use, De Lange et al. presented an example how evaluation methods, originally developed for other stressors and organisms, can also be modified for dung invertebrates. It should also be mentioned that five out of eight posters were directly or indirectly presented by members of the SETAC-Europe advisory group DOTTS.

      On the OECD homepage, two test methods recently standardised can be downloaded:
      1. Guideline OECD No. 228: Dung fly test; Guidance Paper No. 122: Dung beetle test
      2. A detailed proposal for Tier B testing can be found in: Jochmann, R., Blanckenhorn, W., Bussière, L., Eirkson, C.E., Jensen, J., Kryger, U., Lahr, J., Lumaret, J-P., Römbke, J., Wardhaugh, K., Floate, K.D. (2010): How to test non-target effects of veterinary pharmaceutical residues in livestock dung in the field. Integr. Envir. Assess. Management 7: 287–296.
      Author contact information: j-roembke@ect.de; nicole.adler@uba.de
  • Monitoring Data and Post-Registration Studies for PPPs: Generation, Compilation and Use in Environmental Risk Assessment and Management
    • Anne Alix (Ministry of Agriculture, Paris, France) and Martin Streloke (BVL Plant Protection Products, Braunschweig, Germany)

      Monitoring and post-registration studies of Plant Protection Products (PPP) or pesticides, investigate the fate and/or effects of PPP (including active substances and/or their relevant degradation product) in/on the environment when used under realistic conditions in crop protection. There is an increasing need for such investigations throughout Europe that was identified during the decision making process for PPP (Directive 91/414/EEC and its related updating Regulation 1107/2009/EC). Data are needed to address risk assessment uncertainties and to evaluate the efficacy of risk mitigation measures once a product reaches the market. Under directive 2009/128/EC monitoring data might also be used in connection with relevant risk indicators. These studies, beside valuable help in the evaluation of the impact of PPP on the environment, may also be a source of field data needed to feed risk assessment tools and to calibrate ecological models.

      This session allowed communication of methods to monitor the possible impacts of pesticides on the environment and provided a forum for exchanges of views and expertise in a complex area, as many factors may interfere with a comprehensive understanding of the influence of pesticides on ecosystems. Thus, it contributed to the appreciation of potential effects of PPP on the environment to better identify the needs and measures to reach sustainable environmental quality and ecosystem integrity objectives.

      This was the second consecutive year this session was held at a SETAC Europe meeting and it was well attended (room almost full), in spite of a relatively limited number of contributions (15 abstracts received). This illustrates an important demand in a complex area being covered by a limited number of organizations. The session, contrary to the preceding year, gathered a more balanced input from organizations developing/implementing environmental quality monitoring from research laboratories, regulatory organizations and industry. This was an important achievement considering the need to involve all expertise and resources to meet the difficult challenge of generating high quality, widely shared monitoring data. As for the preceding year, the data presented covered environmental aspects with a wide angle, addressing successful monitoring of wildlife, honeybees, aquatic communities, but also the quality of water compartments and food through measurements of chemical residues, mostly pesticides and nutrients. The contributions illustrated protocols designed to monitor effects related to a product in particular (monitoring of birds or pollinators in treated fields) as well a more generic monitoring implemented at the scale of a country aiming at assessing the quality of water with regards to the presence of pesticides (examples in three countries). A contribution presented an attempt to relate monitoring and modeling values for prediction purposes. Finally two contributions illustrated tools developed to serve as indicators of either pesticide use or pesticide footprint in agricultural landscapes. This year's presentations together with the discussions during the session and at the poster session again highlighted the difficulty in generating data that may directly feed risk assessment and risk management, and thus decision making. The session collected some key examples to be worked further in the EMAG PEST advisory group, dedicated to work on recommendations about monitoring studies for environmental effects of pesticides.

      Additional information is available from the advisory group on Environmental Monitoring for Pesticides (EMAG PEST): www.setac.org/node/483

      Author contact information: anne.alix@agriculture.gouv.fr
  • Environmental OMICS: A Global Answer to Environmental Questions
    • Susana Cristobal (Linköping University, Sweden)

      The search for specific indicators of exposure to changes in the environment in which an organism resides has been ongoing for several decades. Even though several single molecule biomarkers have been found, the search has mostly been fruitless. Environmental proteomic research focuses on the analysis of an organism's proteome and the detection of changes in the level of individual proteins in response to environmental stressors. Proteins are key elements of the cellular machinery and changes in the environment will result in changes in the expression of proteins. The study of changes to the gene expression is an alternative and complementary approach. Genes, however, do not show the same diversity in the level of regulation or function that is found for proteins. The applications of the state of art of mass spectrometry-based proteomics in laboratory studies have improved the robustness of the OMICS data available. More remarkable, the introduction of new genomics technologies such as the next generation sequencing for novel biomonitoring has opened a new era in biodiversity protection. Researchers working on environmentally relevant organisms, populations, and communities are increasingly turning to the application of OMICS technologies to answer fundamental questions about the natural world, how it changes over time, and how it is influenced by anthropogenic factors. This area of research is built by a strong cross-disciplinary collaboration between analytical chemistry, system ecology, biology and biochemistry. These collaborations are needed to successfully implement the use of protein expression patterns for the identification of stressors affecting ecosystems. The latest mass spectrometry and genomic technologies could provide quantitative tools to address important ecological research topics, and will give the possibility of applying new, integrated approaches to the assessment of environmental health risks and consequences that will support European policy on environmental health.

      Highlights from this session included:
      1. Introduction of state of the art of mass spectrometry-based proteomics in laboratory studies on species with available sequenced genome.
      2. The availability of recently sequenced genomes of sentinel organisms opennew opportunities in the application of these technologies
      3. Broad variety of applications of gel-based proteomics in field studies that could provide information about assessment and functional analysis of the mechanism of toxicity.
      4. Introduction of new genomics technologies such as the next generation sequencing for novel biomonitoring and evaluation of changes in biodiversity.
      Although the OMICS session did not attract the main attention in this forum, these approaches will have enormous importance the near future of environmental toxicology. In the post-genomic era and with the latest development of technology for genomic, proteomic and metabolomic analysis, we have access to a global answer to environmental problem in a waythat has never been accessible before. It is extremely urgent that the scientific community and regulators pay closer attention to the utility of these technologies and integrate in their own research programs to complement the classical approaches.

      An upcoming conference may be of interest to those SETAC members interested in this topic:

      2011 International Conference on Environmental OMICS http://www.2011enviromics.org/ Environmental OMICS Sciences & Technologies: A System Biology Approach for Research on Environmental Stress and Health Guangzhou, Guangdong Province, China November 8 - 12, 2011

      Author contact information: Susana.Cristobal@liu.se
  • Laboratory and Field Measurements and Alternative Approaches in Bioaccumulation
    • Henriette Selck (Roskilde University, Denmark) and Monika Nendza (Analytisches Laboratorium, Luhnstedt, Germany)

      This session, which was organized by the global SETAC Advisory Group for Advances in Bioaccumulation Assessment, focused on the challenges related to the use of bioaccumulation data for hazard identification of chemicals, PBT screening and risk assessment. Environmental risk assessment (ERA) of contaminants has generally been based on results obtained from controlled laboratory tests providing measures of bioaccumulation and calculations of accumulation factors (e.g., BCF, BAF, BSAF or BMF) for different organisms under varying exposure conditions. These tests have included variation in both abiotic (e.g., pH, salinity, food quantity /quality, contaminant properties such as log Kow) and biotic (e.g., habitat, feeding mode, trophic transport) factors. Consequently, our understanding of the factors controlling bioaccumulation of contaminants under laboratory conditions is fairly good both regarding the terrestrial environment and especially the aquatic environment. However, we are of the general belief that measures of bioaccumulation in laboratory experiments do not translate easily, or not at all, to field data. Another aspect of bioaccumulation is the increasing need for alternative methods preferentially with low cost, ability to screen large chemical inventories and limited use of animals.

      This session centered on two aspects of bioaccumulation:
      1. Extrapolation of laboratory-based measurements of bioaccumulation to field conditions
      2. Alternative approaches in predicting bioaccumulation
      A series of presentations reported case studies examining the relation between bioaccumulation measures in laboratory and field (BCF, BAF, BSAF, BMF, TMF) for inorganic and organic contaminants using both benthic and pelagic organisms as well as a benthic-pelagic food web. One of the biggest challenges to predict bioaccumulation in the field is to determine the main contributors to the discrepancy in bioaccumulation measures between lab and field. Several presentations were given on approaches to minimize uncertainty in bioaccumulation measures (methodological, modelling, etc.) including assessment of knowledge gaps – i.e., which important parameters do we not know enough about and where to direct future research to become better at predicting bioaccumulation.

      The session also included numerous presentations on alternative approaches in bioaccumulation assessment including computational (in silico) models, read-across, and ADME models as well as several presentations on the OSIRIS program on integrated testing strategy (ITS) for bioaccumulation. The lively poster corner discussed the integration of alternative (non)test methods (in silico, in vitro) in an ITS. The predictive power of alternative approaches may depend on the applicability domain of the individual models as well as their combination in the ITS.

      The session was well attended and the papers were all well received.

      Author contact information: selck@ruc.dk, al-luhnstedt@t-online.de
  • Natural Toxins in Ecotoxicology
    • Stephan Pflugmacher (Berlin Institute of Technology, Germany) and Claudia Wiegand (University of Southern Denmark, Odense, Denmark)

      Anthropogenic activities may enhance the concentrations of harmful natural compounds or natural toxins, such as cyanobacterial toxins, increasingly due to high nutrient load in aquatic ecosystems. Furthermore phytoestrogens may leach into the aquatic ecosystem, enhanced due to farming of specific plants. As organisms are exposed to a mixture of anthropogenic as well as natural derived harmful substances, we need to unravel the contribution of those natural toxins. Pollution of ecosystems with nutrients from anthropogenic activities such as intensifying agriculture, has increased eutrophication and its consequences worldwide in aquatic ecosystems. The occurrence of toxic cyanobacteria and algae blooms is nowadays a well documented fact. Among the major impacts of these blooms on aquatic systems are decreased water transparency, lowered oxygen levels, production of odd flavours, and introduction of toxins. In marine and freshwater systems, a wide range of toxins has been identified such as paralytic shell fish toxins, microcystins, anatoxins, cylindrospermopsins acting in the ecosystem food web and ecosystem structure, but also affecting human health via food and drinking water. In marine systems, halogenated compounds produced by organisms are of particular concern. A new scientific field describes the effects of phytoestrogens in the environment. They occur from industrial wastes, but also as drainage from the agricultural fields, or even naturally in a wide range of plants, particular legumes. They thus have the potential of leaching into the soil and into adjacent streams. Mycotoxins have been intensively investigated with regards to human health, however, little is known about their impact at an environmental level.

      The session covered a wide range of topics, from state-of-the-art analytical tools via species differences in capability to biotransform cyanobacterial toxins to bioremediation, biomarker and biosensor aspects. Comparing two limnic mussels, the invasive species Dreissena polymorpha seems to be more capable of biotransforming cyanobacterial toxin than the indigenous and endangered species Unio tumidus; in both species toxin exposure causes energy allocation. A sustainable and cost-effective method was advanced to remove cyanobacterial toxins from lake water for the use as spray irrigation or further purification for drinking water purposes. This method will aid drinking water safety from cyanobacterial toxins in low-income countries. A wide range of harmful marine algae toxins threatens human health via food contamination, requiring reliable quality controls. Biosensors have been introduced for rapid and specific biomarker response, identifying marine alga- derived toxins. Tumor promoting activity and cytotoxicity of cyanobacteria (via gap junctions and MAP-kinase activities) evidenced other toxic compounds from cyanobacteria, besides the main toxin MC-LR. Ozonization proved to be a reliable method for removal of tumor-promoting activities. Protein biomarkers specific for ciguatoxin effects were developed using nano-flow liquid chromatography quadrupole time-of-flight mass spectrometry (Nano-LC-QToF-MS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-ToF-MS). Mixed toxicity of one common and one increasing cyanobacterial toxin was assessed in an environmental realistic scenario.

      Author contact information: stephanpflugmacher@gmail.com, wiegand@biology.sdu.dk
  • Monitoring and Risk-Assessment of Organic compounds in Developing Countries
    • Rialet Pieters (North West University, Potchefstroom, South Africa) and Victor Wepener (University of Johannesburg, Auckland Park, South Africa)

      Developing countries across the globe often have different environmental conditions compared to the thoroughly researched environments of the developed countries. An example would be the colder, water-rich environment of Europe and North America compared to the drier, warmer climes of regions in South America and southern Africa or the tropical climates of Asia, West Africa and South America. The distribution and behaviour of organic pollutants in these tropical and more arid environments are different when compared to the colder climes with high precipitation. The types, numbers and distribution of industries also differ widely between developed and developing countries. Often the processing technologies available in the developing countries are not as "clean" and environmental friendly as those in developed countries. Larger populations in developing countries are poor and lack sanitation, electricity, and running water. Many of these countries are also over-populated. In situations like this, people have to live off the land, burning all sorts of material for cooking and heating that may lead to different levels of polluting compounds than what are usually found in the richer, developing countries. If there is no proper sanitation, or the broken down wastewater treatment plants are not coping with the volumes, untreated sewage finds its way into the aquatic system. The levels and types of anti-retroviral medication in developing countries, rife with AIDS, will be different to that found in the developing countries. Monitoring tools from developed countries need to be adjusted for conditions in developing countries before they can be implemented successfully.. Limited research funding often leads to novel techniques and methods that might work well, but may take longer than a bench-mark method used in a developed country. The above scenarios are but a few obvious differences that might influence the focus of research in the developing countries as well as the results of the research. For this session we solicited contributions which would shed light on the situations regarding levels and cost-effective detection methods/assays/monitoring tools for organic chemicals in the natural environments of developing countries. Contributions regarding risk to the environment and effects posed by the pollution were also welcomed.

      Developing countries often struggle with funding and infrastructure to detect and monitor the levels of polluting compounds in their natural environments. They do have human activities such as industries and bustling cities that may cause pollution, but little policing by regulators of the acceptable levels of restricted compounds in air, water and soil. In this poster session there were contributions mainly from academia on a variety of topics, many of whom reported on levels of selected organic compounds. A few investigated the risk current-use pesticides have on the natural environment and/or humans.

      This session was a poster session only. Abstract contributions from research done in various developing countries were submitted from South America, central Asia, eastern Europe and Africa. Five were from work done in Colombia:
      1. the possible human health risk of chlorpyrifos on potato crop,
      2. the negligible effect glyphosate has on human and wild life when used in combating coca growth in Colombia,
      3. the levels of the organic pollutants in the Cauca River
      4. the levels of brominated flame retardants on rivers from Colombia and Chile.
      5. the probabilistic dose intake of methyl mercury by fish consumers from Colombia was determined with the Monte Carlo simulation.
      Additional posters were presented on issues in other developing countries:
      1. the genotoxic effects of 17α methyltestosterone on Oreochromis niloticus from Brazil were reported on
      2. the biological and chemical organic water pollution in central Asia,
      3. organic contaminants in fish from Cambodia,
      4. levels of selected organic pollutants in the water, sediment and fish from two rivers in Bosnia and Herzegovina
      5. the quality of groundwater in Serbia.
      6. the effectiveness of semi-permeable membrane devices were compared to that of mussels to accumulate organic pollution off the coast of South Africa
      7. the environmental and physicochemical characteristics that determine the Anopheles spp. breeding environment were determined in Cameroon.
      Author contact information: rialet.pieters@nwu.ac.za, victorw@uj.ac.za

Return to the Globe

 
SETAC mission statement Contact SETAC Globe
Contact the SETAC North America office
Contact the SETAC Europe office