In This Issue:
ET&C Perspectives THE PERSPECTIVES COLUMN IS A REGULAR SERIES DESIGNED TO DISCUSS AND EVALUATE POTENTIALLY COMPETING VIEWPOINTS AND RESEARCH FINDINGS ON CURRENT ENVIRONMENTAL ISSUES
The Challenge: Landscape ecotoxicology and spatially explicit risk assessment Natural ecosystems are characterized by high spatial and temporal variability that influence exposure and effects of toxicants on individuals, populations, and communities. Ecological as well as chemical processes exhibit different dynamics on landscape scales compared with standardized and low-dimensional lab or mesocosm test settings; hence, the appropriateness of the ecological risk assessment of chemicals is under continuous discussion. In this contribution, authors from industry, academia, and regulatory authorities offer their specific perspectives describing how they envision developments in the field of landscape ecotoxicology and spatially explicit risk assessment to further improve the environmental risk assessment of chemicals in the future.
Andreas Focks Environmental Risk Assessment Team, Alterra Wageningen Wageningen, The Netherlands
In Response: Why we need landscape ecotoxicology and how it could be advanced—An academic perspective The concept of “landscape ecotoxicology” was introduced in the 1990s by Cairns and Niederlehner [1]. The core idea was to incorporate landscape ecological insights into the risk assessment of chemicals that are dispersed over larger spatial scales (e.g., chemicals widely applied or subject to atmospheric transport). Novel end points that may be affected by chemicals on these scales include patch species richness or diversity, fluxes of nutrients or energy, resilience to nonchemical stressors, habitat connectivity, and heterogeneity. However, this concept had no major influence on chemical risk assessment and ecotoxicological research (0–4 citations/yr according to Web of * Address correspondence to [email protected]. Published online in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/etc.2568 # 2014 SETAC
Science; accessed 19 February 2014), presumably because it was ahead of its time. Still, ecotoxicology has a strong focus on organismic effects and test systems (Figure 1). Only 0.6% of studies on pesticides in freshwater ecosystems were conducted under field conditions transcending the site scale [2]. Consequently, the challenge of chemical risk assessment on larger spatial scales is often perceived as an extrapolation exercise from microcosm/mesocosm systems to more complex natural systems. Unfortunately, comparisons between microcosms/ mesocosms and real-world ecosystems have shown that even for “answering rather simple questions, mesocosms required complicated corrections” [3]. Thus, without knowledge of the effects and processes relevant on the ecosystem or landscape scale, extrapolations remain questionable. Indeed, field-based assessments have challenged thresholds derived from systems of lower complexity for pesticides [4], ionizing chemicals [5], and metals [6]. Reconciliation of these differences can be achieved only through targeted field research. Because of similar debates, ecology witnessed a strong increase (20–50%) in the proportion of field experiments and monitoring [7]. Admittedly, field experiments in ecotoxicology are difficult to conduct because ethical and legal constraints prohibit the deliberate release of chemicals in ecosystems. Nevertheless, chemicals occur widely (e.g., point and diffuse emissions from industrial facilities and agriculture, respectively) and can be studied in experimental settings using well-designed approaches. For example, Liess and Schulz [8] used bypass microcosms fed by stream water, including a control that was disconnected during presumed chemical exposure, to demonstrate population declines following insecticide exposure. Moreover, ecological and ecotoxicological research on the landscape level is faced with natural variability that may mask ecological responses to chemicals. In such cases, advanced multivariate statistical and macroecological tools are available to identify such responses [2], and looking at the community trait composition rather than the taxonomic composition can unravel relationships with specific stressors. The trait-based species at risk (SPEAR) biomonitoring indicator system has been developed to indicate responses of communities to different chemicals [9]. Accompanying laboratory and semifield studies will, of course, be required to understand the mechanisms and explain the mismatch outlined above. For example, a laboratory study with aquatic invertebrates showed that repeated low-dose exposures with a neonicotinoid insecticide in conjunction with competition resulted in a strong long-term culmination of single effects—that is, a population decline that was absent without competition [10]. As a positive role model, the eco(toxico)logical modeling community has embraced the landscape ecotoxicological concept. Several ecological models account for landscape
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farms. Establishing such a farm network for postregistration monitoring of agrochemicals would allow for testing exposure predictions in different landscape contexts as well as monitoring of ecological end points, also with respect to potential mixture effects that are neglected in current regulation. To conclude, chemical risk assessment would gain greater accuracy when accepting the lessons learned by ecologists—that “accurate management decisions cannot be made with confidence unless ecosystem scales are studied” [3]. Ralf B. Schäfer University Koblenz-Landau Landau, Germany REFERENCES
Figure 1. Word cloud resulting from text mining of the abstracts for the 23rd Annual SETAC Europe Meeting, 12–16 May 2013, Glasgow, United Kingdom. Quantitative occurrence of the terms is “tests” (1249), “organism” (766), “species” (1057), “ecosystem” (552), “individual” (315), “communities” (421), “spatial” (179), and “landscape” (93). Note that plural and singular were aggregated.
characteristics such as habitat heterogeneity when predicting the effects of chemicals (e.g., Loos et al. [11]). Such models may help to identify research gaps and predict chemical effects. Highresolution spatiotemporal data are increasingly becoming available and will foster spatially explicit risk predictions that account for landscape characteristics. However, validation against the real world remains pivotal, and modelers should derive end points that can be rigorously tested in field research. The relevance of validation is confirmed in the context of exposure modeling, where strong mismatches between field observations and FOCUS model predictions, which are used for pesticide exposure assessment of surface waters, have been found [12]. This may be partly because these models operate on the site scale, whereas the observed exposure in a stream site depends on the landscape context, such as, for example, whether a site receives exposure from upstream agricultural fields. Thus, spatially explicit catchment-scale exposure models may be needed to arrive at accurate predictions. A stronger involvement of academia in governmental monitoring would also enhance our knowledge of chemical risks on the landscape scale. First, an integration of governmental chemical monitoring and biomonitoring is needed to allow for data analyses on larger scales. In addition, the current monitoring in Europe varies strongly, and the sampling strategy (e.g., how to identify river basin–specific pollutants, measurement frequency of specific chemical groups) should be aligned, involving scientific expertise. Furthermore, the routinely used grab sampling in water monitoring likely misses relevant chemical exposure from diffuse sources and should be complemented by novel tools such as passive samplers [13], which are currently tested by some governmental agencies [14]. Moreover, integrating governmental monitoring with scientific studies on, for example, biomarkers, population genetics, or the landscape context, would deliver invaluable data that scientific studies cannot produce because of resource restrictions. Finally, mandatory postregistration monitoring for chemicals, similar to that implemented for genetically modified organisms, would enable a reliable risk assessment on the landscape scale. In Germany, integrated pestmanagement measures are investigated in so-called demonstration 1194
1. Cairns J, Niederlehner BR. 1996. Developing a field of landscape ecotoxicology. Ecol Appl 6:790–796. 2. Beketov MA, Liess M. 2012. Ecotoxicology and macroecology—Time for integration. Environ Pollut 162:247–254. 3. Schindler DW. 1998. Replication versus realism: The need for ecosystem-scale experiments. Ecosystems 1:323–334. 4. Schäfer RB, von der Ohe PC, Rasmussen J, Kefford JB, Beketov M, Schulz R, Liess M. 2012. Thresholds for the effects of pesticides on invertebrate communities and leaf breakdown in stream ecosystems. Environ Sci Technol 46:5134–5142. 5. Garnier-Laplace J, Geras’kin S, Della-Vedova C, Beaugelin-Seiller K, Hinton TG, Real A, Oudalova A. 2013. Are radiosensitivity data derived from natural field conditions consistent with data from controlled exposures? A case study of Chernobyl wildlife chronically exposed to low dose rates. J Environ Radioact 121:12–21. 6. Clements WH, Cadmus P, Brinkman SF. 2013. Responses of aquatic insects to Cu and Zn in stream microcosms: Understanding differences between single species tests and field responses. Environ Sci Technol 47:7506–7513. 7. Ives AR, Foufopoulos J, Klopfer ED, Klug JL, Palmer TM. 1996. Bottle or big-scale studies: How do we do ecology? Ecology 77:681–685. 8. Liess M, Schulz R. 1999. Linking insecticide contamination and population response in an agricultural stream. Environ Toxicol Chem 18:1948–1955. 9. Schäfer RB, Liess M. 2013. Species at Risk (SPEAR) biomonitoring indicators. In Ferard J, Blaise C, eds, Encyclopedia of Aquatic Ecotoxicology. Springer, Heidelberg, Germany, pp 1063–1073. 10. Liess M, Foit K, Becker A, Hassold E, Dolciotti I, Kattwinkel M, Duquesne S. 2013. Culmination of low-dose pesticide effects. Environ Sci Technol 47:8862–8868. 11. Loos M, Ragas AMJ, Plasmeijer R, Schipper AM, Hendriks AJ. 2010. Eco-SpaCE: An object-oriented, spatially explicit model to assess the risk of multiple environmental stressors on terrestrial vertebrate populations. Sci Total Environ 408:3908–3917. 12. Knäbel A, Meyer K, Rapp J, Schulz R. 2014. Fungicide field concentrations exceed FOCUS surface water predictions: Urgent need of model improvement. Environ Sci Technol 48:455–463. 13. Allan IJ, Vrana B, Greenwood R, Mills GA, Roig B, Gonzalez C. 2006. A “toolbox” for biological and chemical monitoring requirements for the European Union’s Water Framework Directive. Talanta 69:302–322. 14. Emelogu ES, Pollard P, Robinson CD, Webster L, Mckenzie C, Napier F, Steven L, Moffat CF. 2013. Identification of selected organic contaminants in streams associated with agricultural activities and comparison between autosampling and silicone rubber passive sampling. Sci Total Environ 445–446:261–272. DOI: 10.1002/etc.2569 © 2014 SETAC
In Response: Challenges and opportunities for landscape ecotoxicology and spatially explicit risk assessment—An industry perspective
Methods to quantify and communicate the environmental risk associated with the use of chemicals during their life cycle
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(production through disposal) have been developed over the past 50 yr. As the science and protection goals developed, more riskassessment methods have been added (often piecemeal and discipline-focused), leading to guidance becoming ever more comprehensive but also much more complex and in places disjointed. Consequently, current prospective environmental risk-assessment approaches for chemicals were not designed to inform today’s complex risk-management decisions [1], and there is a mismatch between measures of risk and protection goals [2]. For example, it is generally agreed that ecotoxicity, life history, and spatiotemporal distributions of both exposure and populations all influence risk substantially. However, most risk assessments are based on point estimates using ecotoxicological information from laboratory species. Therefore, an integrated approach to address these challenges to transform and harmonize environmental risk assessments is needed. To achieve that, we believe there are 3 key scientific challenges: 1) the definition of protection goals that matter to society and matching measures of risks and benefits, 2) the development and use of accurate and relevant spatially explicit exposure, and 3) mechanistic effects models (e.g., ecological models and toxicokinetic–toxicodynamic models). Ecological risk assessments compare the ecotoxicity of and exposure to a chemical using a tiered approach [3]. Lower-tier assessments represent conservative scenarios of reality and are used to screen, prioritize, and identify chemicals of greatest concern. In contrast, higher-tier approaches consider more accurate representations of reality. Ecotoxicological assessments are analyzed in similar ways across the different classes of chemicals, but they generally ignore spatial factors; conversely, the assessment of exposure varies substantially across different chemical sectors. Differences in exposure assessment are influenced by use patterns; for example, chemicals can be discharged directly, often resulting in pulse-dosed exposure profiles (e.g., plant protection products), or indirectly, typically as continuous exposure profiles (e.g., micropollutants associated with wastewater) into single or multiple environmental compartments (air, soil, water). Lower-tier assessments do not try to characterize the spatial or temporal variability of natural ecosystems and rely on the use of uncertainty factors to derive hazard end points and representative model scenarios to characterize exposure. Where exposure exceeds the hazard end point, it may be necessary to generate additional exposure or hazard data. Within a tiered framework, it may be possible to refine exposure and ecotoxicology using more sophisticated models. A number of higher-tier exposure models have been developed that attempt to characterize the spatial and temporal variability of chemicals in the environment [4–6]. Chemical use patterns coupled with model scenarios that characterize the variables that influence exposure (e.g., landscape, climate, and hydrology) enable risk assessors to assess temporal variations in exposure during a season (e.g., pesticide exposure in edge-offield ditches) and spatial variability within a catchment (e.g., pharmaceuticals and personal care product ingredients within a river catchment). The utility of spatially explicit exposure models to aid risk assessment is dependent on the protection goal and the scale of assessment. For example, in Europe and the United States it is mandatory to estimate likely concentrations of plant protection products in edge-of-field water bodies (ditches, streams, or ponds). Exposure under such scenarios is episodic in nature, and risk assessors have recently attempted to link exposure patterns using toxicokinetic–toxicodynamic models [7] and to account for differences in life histories using ecological
models [8]. Other exposure regimes are considered continuous, such as chemicals used in home and personal care products that enter the environment via untreated or treated wastewater discharges. Higher-tier catchment exposure models have been developed to place a certain river stretch into context with other river stretches in a catchment [9], enabling acceptable risk discussions with risk managers. However, limited effort has been made by the general chemical industry to link spatially and temporally explicit exposure with effects models and to explore the relevance of ecological models at a catchment scale. This reluctance is in part linked to the facts that the approaches are complex and uncertain and that they lack representative ecological scenarios. In addition, the suitability of these approaches has been questioned for scenarios where exposure is considered constant at local and regional scales. But should decisions be taken at these scales? Or is it appropriate to make decisions at a catchment scale where exposure in all stretches will not be constant and seasonal variability in exposure may be important? Irrespective of whether the exposure is constant over time, it will show spatial heterogeneity (at least at larger scales); and because many of the species of concern are mobile and others are present in the compartment of concern during only parts of their life cycle, they will experience spatiotemporal variations in exposure. We believe that there is a need to develop standard scenarios that are representative of different landscapes and environments into which chemicals are released. These scenarios should aid risk assessment at the relevant scales of the protection goals and capture key differences in exposure and ecology (e.g., aquatic, terrestrial). Exposure and ecological models should not be developed in isolation, and there is a need to integrate future developments and link to protection goals at various spatial scales. For example, it may be important to parameterize arid catchments with ephemeral water bodies, characterize the exposure and ecology of these scenarios, and define relevant protection goals. Should all types of water bodies, from ephemeral human-made ditches to pristine natural water bodies rich in biodiversity, be protected in the same way? Should benefits be valued the same irrespective of whether they only affect a small proportion of humankind or whether they improve quality of life for a large proportion of humankind? Should the risks of not using a given chemical also be taken into account (e.g., what would the substitutes be, or would there be changes to landscape structure caused by change of crops)? There is a need to develop catchment and landscape models that account for spatial and temporal variations in exposure in a representative suite of standard scenarios for a range of typologies and ecoregions. The output of risk assessments using spatially explicit and ecological model scenarios needs to enable risk managers to assess both the risk and the benefits during risk management and decision making. Industry strives to maximize the benefits of the chemicals used while minimizing the environmental risks. However, the societal balance cannot be informed by industry or pressure groups alone but should include all stakeholders; therefore, we need clearer protection goals and priorities. Such prioritization will help industry to optimize the potential trade-off between the societal benefits and environmental impacts. If these scientific challenges are addressed, then more ecologically relevant risk assessments can be conducted, which we believe will enable more meaningful risk-management decisions to be made. At larger spatial scales, assessing exposure and effects is challenging. Although resource-intensive, it is possible to monitor exposure concentrations; however, monitoring effects is much more
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difficult, especially at higher levels of organization such as population and ecosystem levels. Modeling approaches could be used to guide monitoring by formulating testable hypotheses, which could then be explored experimentally at smaller scales for model validation. Nonetheless, not everything can be measured and monitored, and there is a need for modeling approaches that link to protection goals at various spatial scales within a tiered framework. Oliver Richard Price Safety and Environmental Assurance Centre, Unilever, Colworth Science Park Sharnbrook, Bedfordshire, United Kingdom Pernille Thorbek Syngenta, Environmental Safety, Jealott’s Hill International Research Centre Bracknell, United Kingdom
REFERENCES 1. Scientific Committee on Health and Environmental Risks, Scientific Committee on Emerging and Newly Identified Health Risks, Scientific Committee on Consumer Safety. 2013. Making risk assessment more relevant for risk management. European Commission, Brussels, Belgium. 2. Forbes VE, Calow P, Grimm V, Hayashi TI, Jager T, Katholm A, Palmqvist A, Pastorok R, Salvito D, Sibly R, Spromberg J, Stark J, Stillman RA. 2011. Adding value to ecological risk assessment with population modeling. Hum Ecol Risk Assess 17:287–299. 3. Munns WR. 2006. Assessing risks to wildlife populations from multiple stressors: Overview of the problem and research needs. Ecol Soc 11:23. 4. Feijtel T, Boeije G, Matthies M, Young A, Morris G, Gandolfi C, Hansen B, Fox K, Holt M, Koch V. 1997. Development of a geography-referenced regional exposure assessment tool for European rivers—GREAT-ER. Contribution to GREAT-ER #1. Chemosphere 34:2351–2373. 5. Anderson PD, D’Aco VJ, Shanahan P, Chapra SC, Buzby ME, Cunningham VL, Duplessie BM, Hayes EP, Mastrocco FJ, Parke NJ, Rader JC, Samuelian JH, Schwab BW. 2004. Screening analysis of human pharmaceutical compounds in US surface waters. Environ Sci Technol 38:838–849. 6. Regulatory Modeling Working Group on Surface Water Models of FOCUS. 2001. FOCUS Surface Water Scenarios in the EU Evaluation Process under 91/414/EEC. Final Report. SANCO/4802/2001-rev-1. Brussels, Belgium 7. Brock TCM, Alix A, Brown CD, Capri E, Gottesburen E, Heimbach F, Lythgo CM, Sculz R, Streloke M. 2010. Linking Aquatic Exposure and Effects in the Risk Assessment of Plant Products. SETAC and CRC Press, Boca Raton, FL, USA. 8. CREAM. 2014. Mechanistic effect models for ecological risk assessment of chemicals. [cited 2014 April 4]. Available from: http://cream-itn.eu/. 9. Williams RJ, Keller VDJ, Johnson AC, Young AR, Holmes MGR, Wells C, Benstead R. 2009. A national risk assessment for intersex in fish arising from steroid estrogens. Environ Toxicol Chem 28:220–230. DOI: 10.1002/etc.2570 © 2014 SETAC
In Response: Regulatory risk assessment and landscape ecotoxicology—A governmental perspective
The purpose of regulatory risk assessment is to provide a scientific basis for an efficient, transparent, and robust decision framework leading to the desired level of protection. The regulatory risk-assessment scheme for plant protection products is based on a tiered system in which a simple first-tier risk assessment is used as a screening step to identify compounds that can be used without unacceptable risk. Concerning plant 1196
protection products, this first-tier approach is stipulated in the legislation, for example, by setting risk ratio triggers [1]. Therefore, only if the first tier demonstrates an unacceptable risk are higher-tier methods used to determine whether an unacceptable risk is likely under conditions that should be more representative of actual field situations. New methods, integrating, for example, elements of landscape ecotoxicology for a more temporally and spatially explicit risk assessment, can thus be used as higher-tier methods to refine a risk. However, it is also important to test such refined riskassessment methodologies and examine whether they fulfill the protection goals as required in the legislation [2]. This also applies to the currently used risk-assessment methodologies and it is of particular importance because there is information indicating that pesticide effects occur in the field [3–5]. Landscape ecotoxicology could help to determine if the current risk-assessment methods are fulfilling the protection goals considering realistic use conditions on the landscape level. A recent report on landscape-level modeling [6] showed that the recovery time for in-field nontarget arthropods estimated from plot experiments (as routinely used for regulatory risk assessment) may be a poor indicator of long-term population impact at the landscape level. This illustrates that a landscapelevel analysis can provide relevant information on the potential impact on populations at the landscape level and help to reduce or address uncertainties in current risk assessment. More of this type of research in which generic—that is, not productspecific—questions related to the validity of risk-assessment methodology is welcome. Regulation (EC) 1107/2009 [2] requires that the protection goals should be fulfilled accounting for the realistic use of plant protection products. It is recognized that plant protection products are often used in crop-protection programs through which several different pesticides are applied simultaneously or subsequently [7]. Risk assessments and subsequent authorization are currently performed for single products, and the methods have very seldom been tested for realistic use conditions. The question is thus whether the “inherent margin of safety” of the current risk assessment appropriately accounts for the effects of other products at the landscape level. Further research would be valuable to settle or propose solutions to this concern. This would require incorporating landscape ecotoxicological analysis because the general protection goals, as stipulated in the legislation, shall address the landscape level. Landscape ecotoxicology is not commonly considered in the current risk-assessment scheme for plant protection product authorization. However, it could be desirable to include some landscape-level elements for a better effect assessment (e.g., landscape structure influencing the mobility of individuals or the influence of refuge areas on the dynamics of populations). Indeed, general protection goals for invertebrates and primary producers often relate to the population level. Nevertheless, the tools available today usually limit risk assessment to the specific protection goals. Specific protection goals in terms of spatiotemporal dimensions are defined by the European Food Safety Authority [7] as nontarget organisms within an individual landscape element (i.e., the agricultural field for the in-field or the edge-of-field for the off-field), with possible acceptable effects lasting for a few days to 1 yr depending on the specific protection goals. When considering spatial dimension for the recolonization of populations, a spatial scale larger than an individual landscape element seems more appropriate because the variability of landscape elements and pesticide application patterns within this landscape are important considerations for
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processes such as external recovery (e.g., Topping and Lagisz [8]). It should be noted that allowing for effects, even if followed by recovery, is not recommended in the aquatic guidance document [5] when pesticides are applied in cropprotection programs characterized by intensive plant protection product use, because current risk-assessment tools do not account for multiple exposure. Therefore, issues related to recovery and recolonization would be more important for infield than for off-field risk assessment. When considering temporal dimension, adjustments of the risk-assessment methods may also be needed because effects such as carryover effects and culmination are important and may take years (several generations) to develop [6,9]. Regulatory risk-assessment schemes should efficiently use resources and limit testing to what is needed. The plant protection product risk-assessment methodology has steadily evolved since the start of the review of active substances in the European Union in the early 1990s to take into account new scientific developments and best available practices. Although the provision of a more precise risk characterization is a desirable development, ecological risk assessment has generally become more complex and time-consuming. From a regulatory perspective, however, it is important to make risk-assessment procedures efficient in everyday work, carefully considering, for example, when time-consuming and complex risk-assessment methodologies are justified. This means that the frequent tradeoff between simplified approaches (often unrealistic but meant to be more conservative) and a more time-consuming and complex approach (often more realistic and meant to be less conservative) needs to be acknowledged and should not necessarily be settled in favor of the latter. Simplified and less demanding risk-assessment methods do not necessarily mean that the underlying science is simple. The simpler and less demanding risk-assessment method could well be developed using advanced scientific knowledge and methods incorporating, for example, experimental, monitoring, or modeled approaches at the landscape level. One example is the attempt of Mineau [10] to develop a predictive model to assess the likelihood of bird mortality based on field studies rather than on laboratory tests for specific types of insecticides (i.e., organophosphorus and carbamates). A number of concerns about this particular approach prevented its use in the context of risk assessment (e.g., monitoring methodology). However, such an approach remains appealing. If developed on the appropriate scientific basis for its application in a regulatory context, it could replace the approach with risk ratios and assessment factors without increasing the time needed for conducting the risk assessment. Another example could be to model how nontarget organisms are affected in a landscape with multiple exposure to plant protection products and through this derive simpler methods (e.g., generic margins of safety, assessment factors) that could be applied in the risk assessment to account for multiple exposure without explicitly including the simulation of the actual effects of these additional pesticides in the riskassessment method. Future directions for efficient and robust regulatory risk assessment and decision making could be to use landscape ecotoxicological approaches to develop and verify simpler regulatory risk-assessment methods to maintain a scientifically reliable risk assessment while keeping the timelines and protection goals stipulated in chemical legislation. Hence, from a regulatory point of view, there are advantages of integrating elements of landscape ecotoxicology when
developing new methods, improving existing approaches, and verifying that risk-assessment methodologies fulfill protection goals. If landscape ecotoxicological approaches are introduced for product-specific risk assessment, however, they ideally should not increase the time needed for completing the riskassessment procedures. Lina Wendt-Rasch Swedish Chemicals Agency (KemI) Sundbyberg, Sweden Veronique Poulsen ANSES (French Agency for Food, Environmental and Occupational Health & Safety) Maisons, Alfort, France Sabine Duquesne German Federal Environment Agency UmweltBundesAmt (UBA) Dessau, Germany
REFERENCES 1. European Commission. 2011. Commission Regulation (EU) No 546/ 2011 of 10 June 2011 implementing Regulation (EC) No 1107/2009 of the European Parliament and of the Council as regards uniform principles for evaluation and authorisation of plant protection products. Official J EurUnion L155:127–155. 2. European Commission. 2009. Regulation (EC) No 1107/2009 of the European Parliament and of the Council of 21 October 2009 concerning the placing of plant protection products on the market and repealing Council Directives 79/117/EEC and 91/414/EEC. Official J Eur Union L309:1–50. 3. Liess M, Brown C, Dohmen P, Duquesne S, Hart A, Heimbach F, Kreuger J, Lagadic L, Reinert W, Maund S, Streloke M, Tarazona JV. 2005. Effects of pesticides in the field. Report from the EU & SETAC Europe Workshop, October 2003, Le Croisic, France. SETAC Press, Brussels, Belgium. 4. Geiger F, Bengtsson J, Berendse F, Weisser WW, Emmerson M, Morales MB, Ceryngier P, Liira J, Tscharntke T, Winqvist C, Eggers S, Bommarco R, Part T, Bretagnolle V, Plantegenest M, Clement LW, Dennis C, Palmer C, Onate JJ, Guerrero I, Hawro V, Aavik T, Thies C, Flohre A, Hanke S, Fischer C, Goedhart PW, Inchausti P. 2010. Persistent negative effects of pesticides on biodiversity and biological control potential on European farmland. Basic Appl Ecol 11:97–105. 5. European Food Safety Authority. 2013. Guidance on tiered risk assessment for plant protection products for aquatic organisms in edgeof-field surface waters. EFSA Panel on Plant Protection Products and Their Residues (PPR). EFSA J 11:3290. 6. Topping CJ, Jung Kjær L, Hommen U, Høye TT, Preuss TG, Sibly RM, van Vliet P. 2014. Recovery based on plot experiments is a poor predictor of landscape-level population impacts of agricultural pesticides. Environ Toxicol Chem, in press DOI: 10.1002/etc.2388. 7. European Food Safety Authority. 2010. Scientific opinion on the development of specific protection goal options for environmental risk assessment of pesticides, in particular in relation to the revision of the Guidance Documents on Aquatic and Terrestrial Ecotoxicology (SANCO/3268/2001 and SANCO/10329/2002). EFSA J 8:1821. 8. Topping CJ, Lagisz M. 2012. Spatial dynamic factors affecting population-level risk assessment for a terrestrial arthropod: An agentbased modeling approach. Hum Ecol Risk Assess 18:168–1180. 9. Liess M, Foit K, Becker A, Hassold E, Dolciotti I, Kattwinkel M, Duquesne S. 2013. Culmination of low-dose pesticide effects. Environ Sci Technol 47:8862–8868. 10. Mineau P. 2002. Estimating the probability of bird mortality from pesticide sprays on the basis of the field study record. Environ Toxicol Chem 21:1497–1506. DOI: 10.1002/etc.2571 © 2014 SETAC
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In Summary:
In the present Perspectives article, scientists and risk assessors working in industry, in academia, and with regulatory authorities have outlined how they envision developments in the field of landscape ecotoxicology that could help to improve environmental risk assessment of chemicals in the future. In response to the challenges for an improved risk assessment as stated in the beginning of the present article, some common points are identified; but contrasting positions also are defined. The academic perspective states that the original idea of “landscape ecotoxicology” was to incorporate landscape ecological insights into the risk assessment of chemicals that are dispersed over larger spatial scales but that ecotoxicology today still focuses strongly on organismic effects and laboratory test systems. It is critically mentioned that the challenge of chemical risk assessment on larger spatial scales is often perceived as a pure extrapolation exercise from microcosm or mesocosm systems to more complex natural systems, thereby neglecting that extrapolations remain questionable without knowledge on the effects and processes relevant on the ecosystem or landscape scale. In addition, a stronger involvement of academia in the governmental monitoring of chemicals and biota would, in the academic perspective, be desirable for several reasons. Finally, in the perspective of the representative of academia, mandatory postregistration monitoring for chemicals would enable a reliable risk assessment on the landscape scale. In the industry perspective, mismatches between prospective approaches and complex risk-management decisions, and between measures of risk and protection goals are currently leading to problems with environmental risk assessment. The industry perspective states that 2 key scientific challenges to overcome these problems are 1) definition of protection goals that matter to society and match measures of risks and benefits, and 2) the development and use of accurate and relevant spatially explicit exposure and mechanistic effects models. The need to develop standard scenarios that are representative of different landscapes and environments is underlined. As concrete measures, chemical and biological monitoring are identified to be an important part of field-scale ecotoxicological research; but the advantage of modeling approaches that link to protection goals at various spatial scales within a tiered framework is further emphasized. In the regulatory perspective, the integration of elements of landscape ecotoxicology into risk assessment is recognized as a higher-tier option for a more temporally and spatially explicit risk assessment; however, the importance of testing such refined risk-assessment methodologies and examining whether they fulfill the protection goals as required in the legislation is
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emphasized. Generic, non–product-specific research that answers questions related to the validity of current or future risk-assessment methodology would be very welcome in the regulatory perspective. One such possible question would be whether the “inherent margin of safety” of the current risk assessment appropriately accounts for the effects of other products at the landscape level. In the regulatory perspective, it is important to consider carefully in which cases time-consuming and complex risk-assessment methodologies are justified so that simplified and less demanding risk-assessment methods are preferred, especially because that does not necessarily mean that the underlying science is simple. All perspectives consider that the landscape dimension plays an important role in the improvement of environmental riskassessment methodology. Concrete ideas and priorities are, however, different among the stakeholders from SETAC’s tripartite structure. Whereas the industry perspective is much in favor of the development of ecological scenarios and related modeling approaches, the academic perspective emphasizes the importance of field monitoring to understand the processes governing ecotoxicology at the landscape level. The regulatory perspective underlines the necessity of daily life applicability of any landscape-scale approaches and calls for further landscape-level research to answer basic and generic questions with relevance for the risk assessment of chemicals. Although not part of this science-oriented perspective, the question of where the money will come from for all of the future research and regulatory directions outlined above is, in practice, also quite relevant. Ideas about what could serve as the best funding mechanism for science that is aimed at entering regulation need to be discussed with the different stakeholders, even if it should be clear that contributions from all sectors are essential. In essence, all positions touch only on a subset of aspects related to the main underlying problem—that is, to ensure minimized impacts of chemicals in the environment. Given that approaches to this challenging and complex task show, as outlined in the present article, a certain level of discordance, the most important things to keep in mind are probably the willingness to cooperate and the acceptance of specific constraints and needs of the respective other parties. Only when pursuing the same objective will industry, academia, and regulatory authorities reach the optimal protection of the environment. Andreas Focks Environmental Risk Assessment Team, Alterra Wageningen Wageningen, The Netherlands DOI: 10.1002/etc.2617 © 2014 SETAC
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ET&C Perspectives THE PERSPECTIVES COLUMN IS A REGULAR SERIES DESIGNED TO DISCUSS AND EVALUATE POTENTIALLY COMPETING VIEWPOINTS AND RESEARCH FINDINGS ON CURRENT ENVIRONMENTAL ISSUES
The Challenge: Landscape ecotoxicology and spatially explicit risk assessment Natural ecosystems are characterized by high spatial and temporal variability that influence exposure and effects of toxicants on individuals, populations, and communities. Ecological as well as chemical processes exhibit different dynamics on landscape scales compared with standardized and low-dimensional lab or mesocosm test settings; hence, the appropriateness of the ecological risk assessment of chemicals is under continuous discussion. In this contribution, authors from industry, academia, and regulatory authorities offer their specific perspectives describing how they envision developments in the field of landscape ecotoxicology and spatially explicit risk assessment to further improve the environmental risk assessment of chemicals in the future.
Andreas Focks Environmental Risk Assessment Team, Alterra Wageningen Wageningen, The Netherlands
In Response: Why we need landscape ecotoxicology and how it could be advanced—An academic perspective The concept of “landscape ecotoxicology” was introduced in the 1990s by Cairns and Niederlehner [1]. The core idea was to incorporate landscape ecological insights into the risk assessment of chemicals that are dispersed over larger spatial scales (e.g., chemicals widely applied or subject to atmospheric transport). Novel end points that may be affected by chemicals on these scales include patch species richness or diversity, fluxes of nutrients or energy, resilience to nonchemical stressors, habitat connectivity, and heterogeneity. However, this concept had no major influence on chemical risk assessment and ecotoxicological research (0–4 citations/yr according to Web of * Address correspondence to [email protected]. Published online in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/etc.2568 # 2014 SETAC
Science; accessed 19 February 2014), presumably because it was ahead of its time. Still, ecotoxicology has a strong focus on organismic effects and test systems (Figure 1). Only 0.6% of studies on pesticides in freshwater ecosystems were conducted under field conditions transcending the site scale [2]. Consequently, the challenge of chemical risk assessment on larger spatial scales is often perceived as an extrapolation exercise from microcosm/mesocosm systems to more complex natural systems. Unfortunately, comparisons between microcosms/ mesocosms and real-world ecosystems have shown that even for “answering rather simple questions, mesocosms required complicated corrections” [3]. Thus, without knowledge of the effects and processes relevant on the ecosystem or landscape scale, extrapolations remain questionable. Indeed, field-based assessments have challenged thresholds derived from systems of lower complexity for pesticides [4], ionizing chemicals [5], and metals [6]. Reconciliation of these differences can be achieved only through targeted field research. Because of similar debates, ecology witnessed a strong increase (20–50%) in the proportion of field experiments and monitoring [7]. Admittedly, field experiments in ecotoxicology are difficult to conduct because ethical and legal constraints prohibit the deliberate release of chemicals in ecosystems. Nevertheless, chemicals occur widely (e.g., point and diffuse emissions from industrial facilities and agriculture, respectively) and can be studied in experimental settings using well-designed approaches. For example, Liess and Schulz [8] used bypass microcosms fed by stream water, including a control that was disconnected during presumed chemical exposure, to demonstrate population declines following insecticide exposure. Moreover, ecological and ecotoxicological research on the landscape level is faced with natural variability that may mask ecological responses to chemicals. In such cases, advanced multivariate statistical and macroecological tools are available to identify such responses [2], and looking at the community trait composition rather than the taxonomic composition can unravel relationships with specific stressors. The trait-based species at risk (SPEAR) biomonitoring indicator system has been developed to indicate responses of communities to different chemicals [9]. Accompanying laboratory and semifield studies will, of course, be required to understand the mechanisms and explain the mismatch outlined above. For example, a laboratory study with aquatic invertebrates showed that repeated low-dose exposures with a neonicotinoid insecticide in conjunction with competition resulted in a strong long-term culmination of single effects—that is, a population decline that was absent without competition [10]. As a positive role model, the eco(toxico)logical modeling community has embraced the landscape ecotoxicological concept. Several ecological models account for landscape
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farms. Establishing such a farm network for postregistration monitoring of agrochemicals would allow for testing exposure predictions in different landscape contexts as well as monitoring of ecological end points, also with respect to potential mixture effects that are neglected in current regulation. To conclude, chemical risk assessment would gain greater accuracy when accepting the lessons learned by ecologists—that “accurate management decisions cannot be made with confidence unless ecosystem scales are studied” [3]. Ralf B. Schäfer University Koblenz-Landau Landau, Germany REFERENCES
Figure 1. Word cloud resulting from text mining of the abstracts for the 23rd Annual SETAC Europe Meeting, 12–16 May 2013, Glasgow, United Kingdom. Quantitative occurrence of the terms is “tests” (1249), “organism” (766), “species” (1057), “ecosystem” (552), “individual” (315), “communities” (421), “spatial” (179), and “landscape” (93). Note that plural and singular were aggregated.
characteristics such as habitat heterogeneity when predicting the effects of chemicals (e.g., Loos et al. [11]). Such models may help to identify research gaps and predict chemical effects. Highresolution spatiotemporal data are increasingly becoming available and will foster spatially explicit risk predictions that account for landscape characteristics. However, validation against the real world remains pivotal, and modelers should derive end points that can be rigorously tested in field research. The relevance of validation is confirmed in the context of exposure modeling, where strong mismatches between field observations and FOCUS model predictions, which are used for pesticide exposure assessment of surface waters, have been found [12]. This may be partly because these models operate on the site scale, whereas the observed exposure in a stream site depends on the landscape context, such as, for example, whether a site receives exposure from upstream agricultural fields. Thus, spatially explicit catchment-scale exposure models may be needed to arrive at accurate predictions. A stronger involvement of academia in governmental monitoring would also enhance our knowledge of chemical risks on the landscape scale. First, an integration of governmental chemical monitoring and biomonitoring is needed to allow for data analyses on larger scales. In addition, the current monitoring in Europe varies strongly, and the sampling strategy (e.g., how to identify river basin–specific pollutants, measurement frequency of specific chemical groups) should be aligned, involving scientific expertise. Furthermore, the routinely used grab sampling in water monitoring likely misses relevant chemical exposure from diffuse sources and should be complemented by novel tools such as passive samplers [13], which are currently tested by some governmental agencies [14]. Moreover, integrating governmental monitoring with scientific studies on, for example, biomarkers, population genetics, or the landscape context, would deliver invaluable data that scientific studies cannot produce because of resource restrictions. Finally, mandatory postregistration monitoring for chemicals, similar to that implemented for genetically modified organisms, would enable a reliable risk assessment on the landscape scale. In Germany, integrated pestmanagement measures are investigated in so-called demonstration 1194
1. Cairns J, Niederlehner BR. 1996. Developing a field of landscape ecotoxicology. Ecol Appl 6:790–796. 2. Beketov MA, Liess M. 2012. Ecotoxicology and macroecology—Time for integration. Environ Pollut 162:247–254. 3. Schindler DW. 1998. Replication versus realism: The need for ecosystem-scale experiments. Ecosystems 1:323–334. 4. Schäfer RB, von der Ohe PC, Rasmussen J, Kefford JB, Beketov M, Schulz R, Liess M. 2012. Thresholds for the effects of pesticides on invertebrate communities and leaf breakdown in stream ecosystems. Environ Sci Technol 46:5134–5142. 5. Garnier-Laplace J, Geras’kin S, Della-Vedova C, Beaugelin-Seiller K, Hinton TG, Real A, Oudalova A. 2013. Are radiosensitivity data derived from natural field conditions consistent with data from controlled exposures? A case study of Chernobyl wildlife chronically exposed to low dose rates. J Environ Radioact 121:12–21. 6. Clements WH, Cadmus P, Brinkman SF. 2013. Responses of aquatic insects to Cu and Zn in stream microcosms: Understanding differences between single species tests and field responses. Environ Sci Technol 47:7506–7513. 7. Ives AR, Foufopoulos J, Klopfer ED, Klug JL, Palmer TM. 1996. Bottle or big-scale studies: How do we do ecology? Ecology 77:681–685. 8. Liess M, Schulz R. 1999. Linking insecticide contamination and population response in an agricultural stream. Environ Toxicol Chem 18:1948–1955. 9. Schäfer RB, Liess M. 2013. Species at Risk (SPEAR) biomonitoring indicators. In Ferard J, Blaise C, eds, Encyclopedia of Aquatic Ecotoxicology. Springer, Heidelberg, Germany, pp 1063–1073. 10. Liess M, Foit K, Becker A, Hassold E, Dolciotti I, Kattwinkel M, Duquesne S. 2013. Culmination of low-dose pesticide effects. Environ Sci Technol 47:8862–8868. 11. Loos M, Ragas AMJ, Plasmeijer R, Schipper AM, Hendriks AJ. 2010. Eco-SpaCE: An object-oriented, spatially explicit model to assess the risk of multiple environmental stressors on terrestrial vertebrate populations. Sci Total Environ 408:3908–3917. 12. Knäbel A, Meyer K, Rapp J, Schulz R. 2014. Fungicide field concentrations exceed FOCUS surface water predictions: Urgent need of model improvement. Environ Sci Technol 48:455–463. 13. Allan IJ, Vrana B, Greenwood R, Mills GA, Roig B, Gonzalez C. 2006. A “toolbox” for biological and chemical monitoring requirements for the European Union’s Water Framework Directive. Talanta 69:302–322. 14. Emelogu ES, Pollard P, Robinson CD, Webster L, Mckenzie C, Napier F, Steven L, Moffat CF. 2013. Identification of selected organic contaminants in streams associated with agricultural activities and comparison between autosampling and silicone rubber passive sampling. Sci Total Environ 445–446:261–272. DOI: 10.1002/etc.2569 © 2014 SETAC
In Response: Challenges and opportunities for landscape ecotoxicology and spatially explicit risk assessment—An industry perspective
Methods to quantify and communicate the environmental risk associated with the use of chemicals during their life cycle
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(production through disposal) have been developed over the past 50 yr. As the science and protection goals developed, more riskassessment methods have been added (often piecemeal and discipline-focused), leading to guidance becoming ever more comprehensive but also much more complex and in places disjointed. Consequently, current prospective environmental risk-assessment approaches for chemicals were not designed to inform today’s complex risk-management decisions [1], and there is a mismatch between measures of risk and protection goals [2]. For example, it is generally agreed that ecotoxicity, life history, and spatiotemporal distributions of both exposure and populations all influence risk substantially. However, most risk assessments are based on point estimates using ecotoxicological information from laboratory species. Therefore, an integrated approach to address these challenges to transform and harmonize environmental risk assessments is needed. To achieve that, we believe there are 3 key scientific challenges: 1) the definition of protection goals that matter to society and matching measures of risks and benefits, 2) the development and use of accurate and relevant spatially explicit exposure, and 3) mechanistic effects models (e.g., ecological models and toxicokinetic–toxicodynamic models). Ecological risk assessments compare the ecotoxicity of and exposure to a chemical using a tiered approach [3]. Lower-tier assessments represent conservative scenarios of reality and are used to screen, prioritize, and identify chemicals of greatest concern. In contrast, higher-tier approaches consider more accurate representations of reality. Ecotoxicological assessments are analyzed in similar ways across the different classes of chemicals, but they generally ignore spatial factors; conversely, the assessment of exposure varies substantially across different chemical sectors. Differences in exposure assessment are influenced by use patterns; for example, chemicals can be discharged directly, often resulting in pulse-dosed exposure profiles (e.g., plant protection products), or indirectly, typically as continuous exposure profiles (e.g., micropollutants associated with wastewater) into single or multiple environmental compartments (air, soil, water). Lower-tier assessments do not try to characterize the spatial or temporal variability of natural ecosystems and rely on the use of uncertainty factors to derive hazard end points and representative model scenarios to characterize exposure. Where exposure exceeds the hazard end point, it may be necessary to generate additional exposure or hazard data. Within a tiered framework, it may be possible to refine exposure and ecotoxicology using more sophisticated models. A number of higher-tier exposure models have been developed that attempt to characterize the spatial and temporal variability of chemicals in the environment [4–6]. Chemical use patterns coupled with model scenarios that characterize the variables that influence exposure (e.g., landscape, climate, and hydrology) enable risk assessors to assess temporal variations in exposure during a season (e.g., pesticide exposure in edge-offield ditches) and spatial variability within a catchment (e.g., pharmaceuticals and personal care product ingredients within a river catchment). The utility of spatially explicit exposure models to aid risk assessment is dependent on the protection goal and the scale of assessment. For example, in Europe and the United States it is mandatory to estimate likely concentrations of plant protection products in edge-of-field water bodies (ditches, streams, or ponds). Exposure under such scenarios is episodic in nature, and risk assessors have recently attempted to link exposure patterns using toxicokinetic–toxicodynamic models [7] and to account for differences in life histories using ecological
models [8]. Other exposure regimes are considered continuous, such as chemicals used in home and personal care products that enter the environment via untreated or treated wastewater discharges. Higher-tier catchment exposure models have been developed to place a certain river stretch into context with other river stretches in a catchment [9], enabling acceptable risk discussions with risk managers. However, limited effort has been made by the general chemical industry to link spatially and temporally explicit exposure with effects models and to explore the relevance of ecological models at a catchment scale. This reluctance is in part linked to the facts that the approaches are complex and uncertain and that they lack representative ecological scenarios. In addition, the suitability of these approaches has been questioned for scenarios where exposure is considered constant at local and regional scales. But should decisions be taken at these scales? Or is it appropriate to make decisions at a catchment scale where exposure in all stretches will not be constant and seasonal variability in exposure may be important? Irrespective of whether the exposure is constant over time, it will show spatial heterogeneity (at least at larger scales); and because many of the species of concern are mobile and others are present in the compartment of concern during only parts of their life cycle, they will experience spatiotemporal variations in exposure. We believe that there is a need to develop standard scenarios that are representative of different landscapes and environments into which chemicals are released. These scenarios should aid risk assessment at the relevant scales of the protection goals and capture key differences in exposure and ecology (e.g., aquatic, terrestrial). Exposure and ecological models should not be developed in isolation, and there is a need to integrate future developments and link to protection goals at various spatial scales. For example, it may be important to parameterize arid catchments with ephemeral water bodies, characterize the exposure and ecology of these scenarios, and define relevant protection goals. Should all types of water bodies, from ephemeral human-made ditches to pristine natural water bodies rich in biodiversity, be protected in the same way? Should benefits be valued the same irrespective of whether they only affect a small proportion of humankind or whether they improve quality of life for a large proportion of humankind? Should the risks of not using a given chemical also be taken into account (e.g., what would the substitutes be, or would there be changes to landscape structure caused by change of crops)? There is a need to develop catchment and landscape models that account for spatial and temporal variations in exposure in a representative suite of standard scenarios for a range of typologies and ecoregions. The output of risk assessments using spatially explicit and ecological model scenarios needs to enable risk managers to assess both the risk and the benefits during risk management and decision making. Industry strives to maximize the benefits of the chemicals used while minimizing the environmental risks. However, the societal balance cannot be informed by industry or pressure groups alone but should include all stakeholders; therefore, we need clearer protection goals and priorities. Such prioritization will help industry to optimize the potential trade-off between the societal benefits and environmental impacts. If these scientific challenges are addressed, then more ecologically relevant risk assessments can be conducted, which we believe will enable more meaningful risk-management decisions to be made. At larger spatial scales, assessing exposure and effects is challenging. Although resource-intensive, it is possible to monitor exposure concentrations; however, monitoring effects is much more
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difficult, especially at higher levels of organization such as population and ecosystem levels. Modeling approaches could be used to guide monitoring by formulating testable hypotheses, which could then be explored experimentally at smaller scales for model validation. Nonetheless, not everything can be measured and monitored, and there is a need for modeling approaches that link to protection goals at various spatial scales within a tiered framework. Oliver Richard Price Safety and Environmental Assurance Centre, Unilever, Colworth Science Park Sharnbrook, Bedfordshire, United Kingdom Pernille Thorbek Syngenta, Environmental Safety, Jealott’s Hill International Research Centre Bracknell, United Kingdom
REFERENCES 1. Scientific Committee on Health and Environmental Risks, Scientific Committee on Emerging and Newly Identified Health Risks, Scientific Committee on Consumer Safety. 2013. Making risk assessment more relevant for risk management. European Commission, Brussels, Belgium. 2. Forbes VE, Calow P, Grimm V, Hayashi TI, Jager T, Katholm A, Palmqvist A, Pastorok R, Salvito D, Sibly R, Spromberg J, Stark J, Stillman RA. 2011. Adding value to ecological risk assessment with population modeling. Hum Ecol Risk Assess 17:287–299. 3. Munns WR. 2006. Assessing risks to wildlife populations from multiple stressors: Overview of the problem and research needs. Ecol Soc 11:23. 4. Feijtel T, Boeije G, Matthies M, Young A, Morris G, Gandolfi C, Hansen B, Fox K, Holt M, Koch V. 1997. Development of a geography-referenced regional exposure assessment tool for European rivers—GREAT-ER. Contribution to GREAT-ER #1. Chemosphere 34:2351–2373. 5. Anderson PD, D’Aco VJ, Shanahan P, Chapra SC, Buzby ME, Cunningham VL, Duplessie BM, Hayes EP, Mastrocco FJ, Parke NJ, Rader JC, Samuelian JH, Schwab BW. 2004. Screening analysis of human pharmaceutical compounds in US surface waters. Environ Sci Technol 38:838–849. 6. Regulatory Modeling Working Group on Surface Water Models of FOCUS. 2001. FOCUS Surface Water Scenarios in the EU Evaluation Process under 91/414/EEC. Final Report. SANCO/4802/2001-rev-1. Brussels, Belgium 7. Brock TCM, Alix A, Brown CD, Capri E, Gottesburen E, Heimbach F, Lythgo CM, Sculz R, Streloke M. 2010. Linking Aquatic Exposure and Effects in the Risk Assessment of Plant Products. SETAC and CRC Press, Boca Raton, FL, USA. 8. CREAM. 2014. Mechanistic effect models for ecological risk assessment of chemicals. [cited 2014 April 4]. Available from: http://cream-itn.eu/. 9. Williams RJ, Keller VDJ, Johnson AC, Young AR, Holmes MGR, Wells C, Benstead R. 2009. A national risk assessment for intersex in fish arising from steroid estrogens. Environ Toxicol Chem 28:220–230. DOI: 10.1002/etc.2570 © 2014 SETAC
In Response: Regulatory risk assessment and landscape ecotoxicology—A governmental perspective
The purpose of regulatory risk assessment is to provide a scientific basis for an efficient, transparent, and robust decision framework leading to the desired level of protection. The regulatory risk-assessment scheme for plant protection products is based on a tiered system in which a simple first-tier risk assessment is used as a screening step to identify compounds that can be used without unacceptable risk. Concerning plant 1196
protection products, this first-tier approach is stipulated in the legislation, for example, by setting risk ratio triggers [1]. Therefore, only if the first tier demonstrates an unacceptable risk are higher-tier methods used to determine whether an unacceptable risk is likely under conditions that should be more representative of actual field situations. New methods, integrating, for example, elements of landscape ecotoxicology for a more temporally and spatially explicit risk assessment, can thus be used as higher-tier methods to refine a risk. However, it is also important to test such refined riskassessment methodologies and examine whether they fulfill the protection goals as required in the legislation [2]. This also applies to the currently used risk-assessment methodologies and it is of particular importance because there is information indicating that pesticide effects occur in the field [3–5]. Landscape ecotoxicology could help to determine if the current risk-assessment methods are fulfilling the protection goals considering realistic use conditions on the landscape level. A recent report on landscape-level modeling [6] showed that the recovery time for in-field nontarget arthropods estimated from plot experiments (as routinely used for regulatory risk assessment) may be a poor indicator of long-term population impact at the landscape level. This illustrates that a landscapelevel analysis can provide relevant information on the potential impact on populations at the landscape level and help to reduce or address uncertainties in current risk assessment. More of this type of research in which generic—that is, not productspecific—questions related to the validity of risk-assessment methodology is welcome. Regulation (EC) 1107/2009 [2] requires that the protection goals should be fulfilled accounting for the realistic use of plant protection products. It is recognized that plant protection products are often used in crop-protection programs through which several different pesticides are applied simultaneously or subsequently [7]. Risk assessments and subsequent authorization are currently performed for single products, and the methods have very seldom been tested for realistic use conditions. The question is thus whether the “inherent margin of safety” of the current risk assessment appropriately accounts for the effects of other products at the landscape level. Further research would be valuable to settle or propose solutions to this concern. This would require incorporating landscape ecotoxicological analysis because the general protection goals, as stipulated in the legislation, shall address the landscape level. Landscape ecotoxicology is not commonly considered in the current risk-assessment scheme for plant protection product authorization. However, it could be desirable to include some landscape-level elements for a better effect assessment (e.g., landscape structure influencing the mobility of individuals or the influence of refuge areas on the dynamics of populations). Indeed, general protection goals for invertebrates and primary producers often relate to the population level. Nevertheless, the tools available today usually limit risk assessment to the specific protection goals. Specific protection goals in terms of spatiotemporal dimensions are defined by the European Food Safety Authority [7] as nontarget organisms within an individual landscape element (i.e., the agricultural field for the in-field or the edge-of-field for the off-field), with possible acceptable effects lasting for a few days to 1 yr depending on the specific protection goals. When considering spatial dimension for the recolonization of populations, a spatial scale larger than an individual landscape element seems more appropriate because the variability of landscape elements and pesticide application patterns within this landscape are important considerations for
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processes such as external recovery (e.g., Topping and Lagisz [8]). It should be noted that allowing for effects, even if followed by recovery, is not recommended in the aquatic guidance document [5] when pesticides are applied in cropprotection programs characterized by intensive plant protection product use, because current risk-assessment tools do not account for multiple exposure. Therefore, issues related to recovery and recolonization would be more important for infield than for off-field risk assessment. When considering temporal dimension, adjustments of the risk-assessment methods may also be needed because effects such as carryover effects and culmination are important and may take years (several generations) to develop [6,9]. Regulatory risk-assessment schemes should efficiently use resources and limit testing to what is needed. The plant protection product risk-assessment methodology has steadily evolved since the start of the review of active substances in the European Union in the early 1990s to take into account new scientific developments and best available practices. Although the provision of a more precise risk characterization is a desirable development, ecological risk assessment has generally become more complex and time-consuming. From a regulatory perspective, however, it is important to make risk-assessment procedures efficient in everyday work, carefully considering, for example, when time-consuming and complex risk-assessment methodologies are justified. This means that the frequent tradeoff between simplified approaches (often unrealistic but meant to be more conservative) and a more time-consuming and complex approach (often more realistic and meant to be less conservative) needs to be acknowledged and should not necessarily be settled in favor of the latter. Simplified and less demanding risk-assessment methods do not necessarily mean that the underlying science is simple. The simpler and less demanding risk-assessment method could well be developed using advanced scientific knowledge and methods incorporating, for example, experimental, monitoring, or modeled approaches at the landscape level. One example is the attempt of Mineau [10] to develop a predictive model to assess the likelihood of bird mortality based on field studies rather than on laboratory tests for specific types of insecticides (i.e., organophosphorus and carbamates). A number of concerns about this particular approach prevented its use in the context of risk assessment (e.g., monitoring methodology). However, such an approach remains appealing. If developed on the appropriate scientific basis for its application in a regulatory context, it could replace the approach with risk ratios and assessment factors without increasing the time needed for conducting the risk assessment. Another example could be to model how nontarget organisms are affected in a landscape with multiple exposure to plant protection products and through this derive simpler methods (e.g., generic margins of safety, assessment factors) that could be applied in the risk assessment to account for multiple exposure without explicitly including the simulation of the actual effects of these additional pesticides in the riskassessment method. Future directions for efficient and robust regulatory risk assessment and decision making could be to use landscape ecotoxicological approaches to develop and verify simpler regulatory risk-assessment methods to maintain a scientifically reliable risk assessment while keeping the timelines and protection goals stipulated in chemical legislation. Hence, from a regulatory point of view, there are advantages of integrating elements of landscape ecotoxicology when
developing new methods, improving existing approaches, and verifying that risk-assessment methodologies fulfill protection goals. If landscape ecotoxicological approaches are introduced for product-specific risk assessment, however, they ideally should not increase the time needed for completing the riskassessment procedures. Lina Wendt-Rasch Swedish Chemicals Agency (KemI) Sundbyberg, Sweden Veronique Poulsen ANSES (French Agency for Food, Environmental and Occupational Health & Safety) Maisons, Alfort, France Sabine Duquesne German Federal Environment Agency UmweltBundesAmt (UBA) Dessau, Germany
REFERENCES 1. European Commission. 2011. Commission Regulation (EU) No 546/ 2011 of 10 June 2011 implementing Regulation (EC) No 1107/2009 of the European Parliament and of the Council as regards uniform principles for evaluation and authorisation of plant protection products. Official J EurUnion L155:127–155. 2. European Commission. 2009. Regulation (EC) No 1107/2009 of the European Parliament and of the Council of 21 October 2009 concerning the placing of plant protection products on the market and repealing Council Directives 79/117/EEC and 91/414/EEC. Official J Eur Union L309:1–50. 3. Liess M, Brown C, Dohmen P, Duquesne S, Hart A, Heimbach F, Kreuger J, Lagadic L, Reinert W, Maund S, Streloke M, Tarazona JV. 2005. Effects of pesticides in the field. Report from the EU & SETAC Europe Workshop, October 2003, Le Croisic, France. SETAC Press, Brussels, Belgium. 4. Geiger F, Bengtsson J, Berendse F, Weisser WW, Emmerson M, Morales MB, Ceryngier P, Liira J, Tscharntke T, Winqvist C, Eggers S, Bommarco R, Part T, Bretagnolle V, Plantegenest M, Clement LW, Dennis C, Palmer C, Onate JJ, Guerrero I, Hawro V, Aavik T, Thies C, Flohre A, Hanke S, Fischer C, Goedhart PW, Inchausti P. 2010. Persistent negative effects of pesticides on biodiversity and biological control potential on European farmland. Basic Appl Ecol 11:97–105. 5. European Food Safety Authority. 2013. Guidance on tiered risk assessment for plant protection products for aquatic organisms in edgeof-field surface waters. EFSA Panel on Plant Protection Products and Their Residues (PPR). EFSA J 11:3290. 6. Topping CJ, Jung Kjær L, Hommen U, Høye TT, Preuss TG, Sibly RM, van Vliet P. 2014. Recovery based on plot experiments is a poor predictor of landscape-level population impacts of agricultural pesticides. Environ Toxicol Chem, in press DOI: 10.1002/etc.2388. 7. European Food Safety Authority. 2010. Scientific opinion on the development of specific protection goal options for environmental risk assessment of pesticides, in particular in relation to the revision of the Guidance Documents on Aquatic and Terrestrial Ecotoxicology (SANCO/3268/2001 and SANCO/10329/2002). EFSA J 8:1821. 8. Topping CJ, Lagisz M. 2012. Spatial dynamic factors affecting population-level risk assessment for a terrestrial arthropod: An agentbased modeling approach. Hum Ecol Risk Assess 18:168–1180. 9. Liess M, Foit K, Becker A, Hassold E, Dolciotti I, Kattwinkel M, Duquesne S. 2013. Culmination of low-dose pesticide effects. Environ Sci Technol 47:8862–8868. 10. Mineau P. 2002. Estimating the probability of bird mortality from pesticide sprays on the basis of the field study record. Environ Toxicol Chem 21:1497–1506. DOI: 10.1002/etc.2571 © 2014 SETAC
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In Summary:
In the present Perspectives article, scientists and risk assessors working in industry, in academia, and with regulatory authorities have outlined how they envision developments in the field of landscape ecotoxicology that could help to improve environmental risk assessment of chemicals in the future. In response to the challenges for an improved risk assessment as stated in the beginning of the present article, some common points are identified; but contrasting positions also are defined. The academic perspective states that the original idea of “landscape ecotoxicology” was to incorporate landscape ecological insights into the risk assessment of chemicals that are dispersed over larger spatial scales but that ecotoxicology today still focuses strongly on organismic effects and laboratory test systems. It is critically mentioned that the challenge of chemical risk assessment on larger spatial scales is often perceived as a pure extrapolation exercise from microcosm or mesocosm systems to more complex natural systems, thereby neglecting that extrapolations remain questionable without knowledge on the effects and processes relevant on the ecosystem or landscape scale. In addition, a stronger involvement of academia in the governmental monitoring of chemicals and biota would, in the academic perspective, be desirable for several reasons. Finally, in the perspective of the representative of academia, mandatory postregistration monitoring for chemicals would enable a reliable risk assessment on the landscape scale. In the industry perspective, mismatches between prospective approaches and complex risk-management decisions, and between measures of risk and protection goals are currently leading to problems with environmental risk assessment. The industry perspective states that 2 key scientific challenges to overcome these problems are 1) definition of protection goals that matter to society and match measures of risks and benefits, and 2) the development and use of accurate and relevant spatially explicit exposure and mechanistic effects models. The need to develop standard scenarios that are representative of different landscapes and environments is underlined. As concrete measures, chemical and biological monitoring are identified to be an important part of field-scale ecotoxicological research; but the advantage of modeling approaches that link to protection goals at various spatial scales within a tiered framework is further emphasized. In the regulatory perspective, the integration of elements of landscape ecotoxicology into risk assessment is recognized as a higher-tier option for a more temporally and spatially explicit risk assessment; however, the importance of testing such refined risk-assessment methodologies and examining whether they fulfill the protection goals as required in the legislation is
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emphasized. Generic, non–product-specific research that answers questions related to the validity of current or future risk-assessment methodology would be very welcome in the regulatory perspective. One such possible question would be whether the “inherent margin of safety” of the current risk assessment appropriately accounts for the effects of other products at the landscape level. In the regulatory perspective, it is important to consider carefully in which cases time-consuming and complex risk-assessment methodologies are justified so that simplified and less demanding risk-assessment methods are preferred, especially because that does not necessarily mean that the underlying science is simple. All perspectives consider that the landscape dimension plays an important role in the improvement of environmental riskassessment methodology. Concrete ideas and priorities are, however, different among the stakeholders from SETAC’s tripartite structure. Whereas the industry perspective is much in favor of the development of ecological scenarios and related modeling approaches, the academic perspective emphasizes the importance of field monitoring to understand the processes governing ecotoxicology at the landscape level. The regulatory perspective underlines the necessity of daily life applicability of any landscape-scale approaches and calls for further landscape-level research to answer basic and generic questions with relevance for the risk assessment of chemicals. Although not part of this science-oriented perspective, the question of where the money will come from for all of the future research and regulatory directions outlined above is, in practice, also quite relevant. Ideas about what could serve as the best funding mechanism for science that is aimed at entering regulation need to be discussed with the different stakeholders, even if it should be clear that contributions from all sectors are essential. In essence, all positions touch only on a subset of aspects related to the main underlying problem—that is, to ensure minimized impacts of chemicals in the environment. Given that approaches to this challenging and complex task show, as outlined in the present article, a certain level of discordance, the most important things to keep in mind are probably the willingness to cooperate and the acceptance of specific constraints and needs of the respective other parties. Only when pursuing the same objective will industry, academia, and regulatory authorities reach the optimal protection of the environment. Andreas Focks Environmental Risk Assessment Team, Alterra Wageningen Wageningen, The Netherlands DOI: 10.1002/etc.2617 © 2014 SETAC
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Copyright of Environmental Toxicology & Chemistry is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
