Bienes históricos y culturales (Museo)

drivers (I)

362

Towards a systematic approach for the assessment of multiple stressors: Making Aquatic Ecosystems Great Again (MAEGA)

D.J. Baird, Environment Canada; R. Schaefer, University Koblenz Landau / Institute for Environmental Sciences; C.B. Choung, Environment Canada/Canadian Rivers Institute / Department of Biology; A. Bush, Environment and Climate Change Canada; S. Bracewell, Wageningen University & Research / Department of Aquatic Ecology and Water Quality Management; A. Chariton, Macquarie University / Molecular Ecology and Toxicology; Z. Compson, Environment and

Climate Change Canada; K. Dafforn, Macquarie University / Evolution and Ecology Reserach Centre; E.L. Johnston, University of New South Wales / Evolution and Ecology Research Centre; K. Korbel, Macquarie University; D. Lapen, University of New South Wales; M. Mayer-Pinto, University of New South Wales / Evolution Ecology Research Centre School of Biological Earth and Environmental Sciences; W. Monk, Environment and Climate Change Canada; A. O'Brien, University of Melbourne; N. Rideout, Environment and Climate Change Canada; K. Sumon, R. Verdonschot, Wageningen University; P. van den Brink, Alterra/Wageningen UR / Aquatic Ecology and Water Quality Management Group b Alterra

In the Anthropocene, ecosystems are exposed to a range of stressors that if not properly managed can lead to ecosystem state shifts and significant losses in ecosystem services. We held a workshop (September 2017 in Wageningen, The Netherlands) to develop a conceptual framework to assess the effects of multiple stressors on the structure and functioning of aquatic ecosystems. This framework was subsequently applied to three ecosystem types (ditches, floodplains and harbours). The proposed framework consists of two parts: an environmental filter and a transmitting function to allow effects to propagate to higher levels of biological organisation. Applying the framework consists of the following steps: 1) Select an ecosystems of concern; 2) Identify stressors and potential interactions; 3) Identify receptors/sensitive groups for each stressor; 4) Identify stressor-response relationships and group stressors according to their mode of action; 5) Construct an ecological model that includes relevant functional groups and endpoints; 6) Predict the resultant impact of multiple stressors; 7) Confront the predictions with experimental and monitoring data and 8) Adjust the ecological model if needed. Steps 7 and 8 can be repeated until a satisfactory match between model predictions and experimental and monitoring data has been obtained. The talk will present the details of the framework and will also briefly introduce the three case studies developed during the workshop and discuss the commonalities and differences in approaches between the three case studies which all used the framework as a starting point.

363

Predicting the response of ditch ecosystems to multiple stressors

S. Bracewell, Wageningen University & Research / Department of Aquatic Ecology and Water Quality Management; R. Verdonschot, Wageningen Environmental Research (Alterra); R. Schaefer, University Koblenz Landau / Institute for Environmental Sciences; A. Bush, University of New Brunswick / Environment Canada; D. Lapen, Agriculture and Agri-Food Canada; K. Sumon, Wageningen University & Research Centre / Aquatic Ecology and Water Quality Management; P. van den Brink, Alterra/Wageningen UR / Aquatic Ecology and Water Quality Management Group b Alterra

Until recently, our knowledge of the net effects of multiple stressors on freshwater ecosystems has been limited. We still lack a general framework that can integrate known effects of individual stressors on organisms and predict how these effects propagate through higher levels of biological organisation. In light of this, a workshop was held at Wageningen University and Research, the Netherlands, (September 2017) to determine the current state of knowledge of multiple stressor effects on aquatic ecosystems and to assess how these effects can be better predicted. The workshop was attended by experts from the Netherlands, Australia, Germany, and Canada and covered a range of ecosystem types considered to be at high risk from multiple stressors. The workshop resulted in a “best-approach” conceptual framework for assessing multiple stressor effects on aquatic ecosystems. The framework was subsequently applied to three case studies: harbours, agricultural drainage ditches, and floodplains. Here, we present the application of this framework to agricultural drainage ditches. Agricultural drainage ditches are an under-appreciated and undervalued habitat for a range of aquatic and terrestrial organisms. Although these man-made features can maintain high biodiversity in agriculture landscapes, they are often ignored for their conservation value and are not protected under the EC Water Framework Directive 2000/06/EC. Using the framework developed during the Wageningen workshop, we developed a conceptual food-web model using functional groups to assess known direct effects of stressors on ditch communities. We identified the most important stressors (nutrients, pesticides, dredging and mowing, salinisation, and siltation) impacting ditch communities and performed a literature search for each stressor-functional group combination to identify sensitive and non-sensitive groups. We also reviewed the literature on experiments using at least two of the identified stressors and identified potential interactions. The conceptual food-web model was updated using this knowledge to capture interactions. Finally, the conceptual model and its predictions regarding the response to multiple stressors will be compared to large scale ditch biomonitoring data to assess the

validity/predictive power of the model. We demonstrate that the framework provides a useful conceptual template to assess and predict multiple stressor impacts as well as to unravel research gaps.

364

The combined effects of nutrients and thiacloprid on macrofauna invertebrate population and community responses

H. Barmentlo, Leiden University; M. Schrama, CML Leiden University / Conservation Biology; K.J. Musters, Leiden University / Institute of Environmental

Sciences; P.M. Van Bodegom, CML Leiden University / Institute of Environmental Science CML; G. de Snoo, Leiden University / Institute of Environmental Sciences; M.G. Vijver, CML Leiden University / Conservation Biology

Ditches are commonly used to control for fluctuating groundwater tables in agricultural landscapes. They provide a strong linkage between agricultural fields and adjacent water bodies as they are a common sink for agricultural chemicals such as neonicotinoid insecticides and fertilizers. As these agrochemicals are bound to co-occur in the ditches, we aimed to study their combined effects on aquatic invertebrate population and community responses. To this end, we exposed caged organisms and naturally assembled invertebrate communities to environmentally realistic thiacloprid and nutrient concentrations at the Living Lab facility. The Living Lab facility consists of 36 naturally colonized ditches of 25 cm depth in which experiments can be performed under outdoor conditions. We found adverse effects of thiacloprid on several population responses at concentrations that were comparable or far lower than laboratory derived LOECs as obtained from literature. These effects were less pronounced when organisms were exposed under nutrient enriched conditions. In addition, we observed significant dissimilarity between the naturally assembled communities under the influence of both thiacloprid and nutrients. These shifts were largely represented by a severe decrease in insect abundance under thiacloprid exposure. This decrease was not observed in ditches that received both thiacloprid and nutrient application. Thus, we showed the importance of nutrient enrichment (and the resulting increase in primary production) for coping with thiacloprid induced toxicity. This might explain the difficulties as often faced when extrapolating lab to field data and the other way around.

365

Macroinvertebrate communities across a gradient of multiple stressors from agricultural land use in Romanian streams

V.C. Schreiner, M. Link, S. Kunz, E. Szöcs, University of Koblenz Landau; B. Vogler, B. Beck, Eawag Swiss Federal Institute of Aquatic Science and Technology; K.P. Battes, M. Cimpean, Babeș-Bolyai University; E. Vermeirssen, Ecotox Centre Eawag-EPFL / Aquatic Ecotoxicology; H. Singer, Eawag, Swiss Federal Institute of Aquatic Science and Technology / Environmental Chemistry; J. Hollender, Eawag / Environmental Chemistry; R. Schaefer, University Koblenz Landau / Institute for Environmental Sciences

Pesticides from agricultural usage are one of the major drivers of biodiversity loss in freshwater ecosystems. Their entry pathways are mainly related to pesticide use agriculture. To differentiate pesticide toxicity and other agricultural stressors, we conducted a field study in Eastern Europe (Romania), where agricultural intensity varies, ranging from high to low intensity (extensive) agriculture relying largely on human or animal labour (e.g. horse ploughs). We assumed that, in contrast, to pesticide toxicity, excessive nutrient and sediment input would be unrelated to agricultural intensity. Consequently, this would allow distinguishing effects from pesticides and these other stressors. We analysed the relationships between pesticide toxicity and other agricultural stressors. Additionally, we analysed combined and individual effects of these variables on the biodiversity, as well as on the composition of stream macroinvertebrate communities. We examined 19 low-order streams across a gradient of agricultural intensity in terms of average field sizes. Pesticide concentrations were investigated using two different passive sampling methods. Firstly, we used styrene-divinylbenzene (SDB) disks to sample hydrophilic compounds, which enabled the determination of approximate time-weighted pesticide concentrations in streams during heavy rainfall events. Secondly, we used polydimethylsiloxane sheets (PDMS) focusing on the detection of lipophilic pyrethroids and organophosphates. The toxicity of the 88 detected pesticides was assessed using the sum toxic unit (sumTU). Stream

macroinvertebrate communities were sampled twice, using a quantitative multi-habitat-sampling. This allowed the analysis of relationships between the community composition and diversity with a gradient of pesticide toxicity in interaction with additional agricultural stressors. The toxicity gradient originated from pesticides and nutrients (NH4+_{) showed no relationship to the intensity of} agriculture expressed as the average size of the adjacent fields. This indicates that pesticides and nutrients co-occur independently of agricultural intensity. How and to which extent, in terms of effect size, the communities are affected by the pesticide gradient and the additional presence of other stressors originating from agricultural land use will be presented during the conference.

366

Daily temperature variation determines the toxicity of a pesticide mixture

V. Delnat, T.T. Tran, L. Janssens, KU Leuven / Biology; R. Stoks, University of Leuven / Department of Biology

Synergistic interactions between pesticides in mixtures and between pesticides and warming may improve the efficacy of vector control. Particularly, synergistic interactions between biopesticides and chemical pesticides would be promising as these could potentially result in the combination of efficacy of control, slowdown of resistance build-up and lower ecological damage. One understudied aspect of global warming is the increase in daily temperature variation (DTV). While DTV may increase the toxicity of chemical pesticides, it is unknown whether it also interacts synergistically with biopesticides, and magnifies the toxicity of pesticide mixtures. We tested whether DTV influences the toxicity of pesticides with a

80 SETAC Europe 28th Annual Meeting Abstract Book

different mode of action (the chemical pesticide Chloorpyrifos, CPF, and the biopesticide Bti) in the mosquito Culex pipiens. We expected that the effects of the single exposures are strengthened in the presence of DTV. In addition, we tested whether there is an interaction between CPF and Bti and whether this interaction is magnified in the presence of DTV. We crossed three DTV treatments (no DTV, a small DTV of 7°C and a large DTV of 14°C) with four pesticide treatments (a solvent control, single CPF exposure, single Bti exposure and exposure to the CPF-Bti mixture). We studied effects on a proxy for population growth rate (r’) and its key components. The experiment was done in three steps: (i) 4-day exposure in L4 to DTV, (ii) 2-day exposure to DTV and the pesticide treatment and (iii) exposure to DTV until metamorphosis. The presence of a large DTV increased the toxicity (based on r’) of the chemical pesticide, but not the biopesticide. Moreover, a large DTV changed the toxicity of the CPF-Bti mixture. For example, the presence of large DTV removed the antagonistic interaction effect on total mortality which was present in the absence of DTV and in the presence of small DTV. Our results underscore the importance of considering DTV as a factor shaping not only the toxicity of pesticides but also the interaction type between pesticides in mixtures. Given DTV occurs in all natural populations and may strongly differ between latitudes, DTV may be an important factor causing a mismatch between toxicity studies done in the lab at constant temperatures and the toxocity of pesticides and their mixture in the real world.

367

Warming and daily temperature fluctuations make the pesticide chlorpyrifos more toxic in Ischnura elegans damselflies

J. Verheyen, R. van Roo, KU Leuven / Biology; R. Stoks, University of Leuven / Department of Biology

Current risk assessment of pesticides fails to protect aquatic biodiversity. A key reason is the lack of realism: pesticides are tested under ideal laboratory conditions at one mean temperature. To strengthen current risk assessment it is crucial to incorporate effects of global warming on the toxicity of pesticides. Global warming studies largely overlook that climate scenarios also predict stronger daily temperature fluctuations (DTFs), which can have greater fitness effects for organisms than increases in mean temperatures. While many pesticides (like organophosphates) get more toxic at higher temperatures, it is largely unknown how DTFs influence the pesticide toxicity. We examined a multiple-stressor scenario where we quantified the single and combined effects of (i) increases in mean temperature and (ii) in DTF, and (iii) exposure to the pesticide chlorpyrifos (CPF) in larvae of high- and low-latitude populations of Ischnura elegans damselflies. CPF imposed mortality and more so in high-latitude compared to low-latitude larvae. Moreover, CPF was more toxic at 24°C compared to 20°C, confirming the higher toxicity of organophospates at higher temperatures. A key finding was that DTF also increased the toxicity of CPF, providing novel evidence that DTFs can amplify the toxicity of pesticides. Furthermore, the increased toxicity of CPF by DTF was more pronounced at 24°C. This novel pattern is likely general as at a higher mean temperature, DTF will expose the animals to even higher temperatures during the daily cycle, thereby increasing exposure to stressful temperatures. Also, the negative effect of CPF on larval growth strongly depended on DTF. CPF did decrease larval growth considerably, but only in the 10°C DTF treatment. Probably the higher metabolic demands for cell maintenance in the 10°C DTF treatment resulted in lower growth rates. Our results convincely show that the organophosphate pesticide chlorpyrifos is not only more toxic to damselfly larvae at the higher mean temperature (24°C) but also at higher daily temperature fluctuations (DTF of 10°C), both in terms of lethal effects (mortality) and sublethal effects (growth rate). Notably, the synergistic effect of DTF on pesticide sensitivity was higher at the high temperature. Our results highlight that incorporating higher mean temperatures and especially DTFs in ecotox testing will increase the realism of the risk assessment of pesticides under global warming.

PBT/vPvB & PMT/vPvM substances and Non-extractable

residues (NER): Scientific strategies, Analytical challenges

and Regulatory Issues (I)

368

RPLC-HILIC and SFC coupled with Mass Spectrometry: Polarity Extended Screening of organic molecules in the aqueous environment

S. Bieber, Technical University of Munich / Chair of Urban Water Systems Engineering; S. Grosse, T. Letzel, Technical University of Munich

Trace organic compounds are important in environmental analysis, because they impact water quality and introduce potential (eco)toxicological effects. Current analytical methods mostly rely on gas chromatography (GC) or reversed-phase liquid chromatography (RPLC) coupled with (tandem) mass spectrometry. However, neither method can easily separate very polar molecules. Two chromatographic separation strategies, a serial RPLC- hydrophilic interaction liquid chromatography (RPLC-HILIC) coupling and an analytical scale supercritical fluid chromatography (SFC) system will be presented, and their separation effectiveness as polarity-extended chromatographic methods for 274 environmentally relevant compounds were validated in a recent publication [1]. Compounds tested were grouped into three polarity classes, “very polar” log D (pH

7) below -2.5, “polar” log D (pH 7) -2.5 to +2, and “non-polar” log D (pH 7) higher than +2). Nearly all compounds could be retained in both systems with relative standard deviations of retention times (RT) (n = 6) typically between 2 and 5%. Both techniques have considerable benefits when combined with accurate mass spectrometric detection. Molecules RT and accurate mass were recorded in a database for each set up. This information was used for compound screening measurements like “hidden-target screening” in complex environmental matrices (such as wastewater treatment plant effluents). Results of both techniques are complementary and useful for all types of molecules polarity. In this study, more than 80 percent of the compounds found in wastewater treatment plant effluent samples possessed a negative log D (pH 7) value. This result highlights the basic necessity to include “very polar” compounds in water monitoring techniques and protocols. [1] S. Bieber, G. Greco, S. Grosse, T. Letzel: RPLC-HILIC and SFC with mass spectrometry: Polarity-extended organic molecule screening in environmental (water) samples. Analytical Chemistry 2017, 89 (15), 7907-7914 (DOI:

10.1021/acs.analchem.7b00859).

369

Removal options and transformations of persistent mobile organic chemicals during production of drinking water

A. TOUFFET, IC2MP CNRS; H. Gallard, IC2MP; B. Sieira, University of Santiago de Compostela; j. Chokki, b. teychene, IC2MP CNRS; R. Montes, University of Santiago de Compostela; R. Rodil, University of Santiaga de Compostela; J. Quintana, University of Santiago de Compostela

Persistent Mobile Organic chemicals (PMOCs) are well water soluble, non-volatile and are thus mobile in the water cycle. Because of their intrinsic properties, they are able to penetrate natural and artificial barriers and may constitute a threat for drinking water. Advanced treatments like activated carbon and oxidation processes can be used to limit the presence of organic micropollutants in drinking water. However, low removal by activated carbon is expected for PMOCs because of their high polarity. The behaviour of selected PMOCs identified in water resources were evaluated at lab-scale for their removal by different options including powdered activated carbon (PAC), high pressure membrane processes and transformation by ozone and chlorine. Highly polar PMOCs such as adamantan-1-amine (Log D = -2.34), trifluoromethanesulfonate (Log P = -1.35) and ?-caprolactam (Log P = 0.15) were not removed by PAC even for very high doses. Only naphtalenesulfonate (Log P = - 0.41) was fully removed for 5 mg L-1 _{PAC. The other PMOCs i.e. aromatic} sulfonates, aromatic guanidines, phenols, were removed significantly for high PAC doses, but that are not compatible with drinking water production. Most of the PMOCs identified in water resources showed a very low reactivity with ozone with rate constants below 100 M-1 _s-1 _{and thus will not be transformed during ozonation} of drinking water. Two aromatic guanidines, the 1,3-diphenylguanidine and the 1,3-di-o-tolylguanidine, an olefinic sulfonate and an amine compound, the N-benzyldimethylamine, were rapidly transformed by ozone. Transformation of both guanidines occurred in few seconds at neutral pH during disinfection by chlorine. Chlorinated and hydroxylated analogues, and products of cleavage and cyclization were identified. US EPA toxicity prediction tool showed that chlorinated and hydroxylated analogues would be more toxic than the parent compound, which was confirmed by Microtox acute toxicity test for Cl2/guanidine ratio of 1 and 10. Thus, reactions with chlorine during disinfection can be a source of new, persistent and more toxic chemicals in drinking water Some PMOCs like ?-caprolactam, halogenated methanesulfonates, adamantan-1-amine and triazine compounds will neither be removed by adsorption on activated carbon nor transformed by oxidation processes and could thus be present in drinking water. High pressure membrane processes would constitute the ultimate barrier for these compounds.

370

Removal of polar micropollutants from drinking water by reverse osmosis: a pilot scale study

V. Albergamo, University of Amsterdam/IBED Institute / IBED; E. Cornelissen, KWR Watercycle Research Institute; B. Blankert, Oasen; W. Knibbe, University of Wageningen; W. Van der Meer, Oasen & University of Twente; P. de Voogt, University of Amsterdam / IBED

The occurrence of polar micropollutants (MPs) in drinking water sources is regarded as one of the most challanging issue of our times. Polar MPs can preferentially remain in the water phase during environmental and water treatment processes, potentially reaching finished drinking water and thus raising concern over adverse effects to human health. In The Netherlands reverse osmosis (RO) has been proposed as a stand-alone treatment capable of producing impeccable drinking water from riverbank filtrate. State-of-the-art RO can be highly effective in