Quellen und Verteilung von Nanomaterialien in der aquatischen Umwelt

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1 Quellen und Verteilung von Nanomaterialien in der aquatischen Umwelt Fadri Go/schalk Kollek'vgesellscha. für Forschung und Beratung, Strada, Schweiz ETH Ins'tute for Environmental Decisions, Natural and Social Science Interface, ETH Zurich Berlin: FachDialog Wasser Bundesumweltministerium Outline 1. What s the problem with environmental release (and fate) of engineered nanomaterial? 2. Methodological approaches 3. Case studies 4. Short overview literature and risk estimations 1

2 1. Do nanomaterials reach the environment? Ma terials Science & Technology From Prof. Nowack,2009, Empa Switzerland Environmental release Nano-TiO 2 via wastewater Diffusive release Westerhoff et al., J. Environ. Monitor.13: 1195 (2011) Go/schalk et al Environmental Science and Technololgy 43, Sun, T.Y., Go/schalk, F., Hungerbühler, K., Nowack, B., Environmental PolluXon e- 76. Sun et al

3 2. Approaches: Multimedia Mass- Balance Modeling MacLeod, M., Scheringer, M., McKone, T.E., Hungerbuhler, K., The State of MulXmedia Mass- Balance Modeling in Environmental Science and Decision- Making. Environmental Science & Technology 44, Mass balance in the nano context, our examples later: Go/schalk et al Sun et al Geometry of emissions and transport/transformation Adapted from Go/schalk et al E M & S 25, Overview on nanomaterial based environmental exposure research: Go/schalk, F., Sun, T.Y., Nowack, B., Environmental PolluXon 181, ! 3

4 Basic concept: transfer coefficients (TC) modeled as contaminant specific values m 1j. V j 0 TC js = m js m 1 rj r m js V s m ij m = m compound = m product c (i) dmi ( j ) (t) dt input output = m (i) rj (t) m (i) ( j ) js (t) + G i r =1 s=1 generaxon/degradaxon Mass flow analysis European generic curves illustraxng total engineered nanomaterial (ENM) overall transfer between natural, human and technical Steinfeldt et al Environmental exposure to engineered nanomaterial from four applicaxons: nanotio2 in paint, nanozno in glass coaxngs, MWCNT in epoxy plates, and nanocellulose as a paper addixve. Nanosustain report EU FP27. 8! 4

5 Engineered nanomaterial use volumes Sun, T.Y., Go/schalk, F., Hungerbühler, K., Nowack, B., Comprehensive probabilisxc modelling of environmental emissions of engineered nanomaterials. Environmental PolluXon e- 76. Distribution to product categories, example nano- TiO 2 (in % of total nano-tio 2 ) Product category Mean Min-Max Cosmetics Filters Surface treatment Plastics Electronics Paint Glas & Ceramics Light Bulbs Metals Batteries Textiles Ink Go/schalk et al

6 Examples of Intermediate Results Go/schalk et al Sedimentation process: exercise nano- TiO 2 density.default(x = met8nach10) Density prior likelihood (data) posterior (MCMC) posterior (bootstrapping) Bayes updaxng: P(data hypothesis) P(hypothesis) P(hypothesis data) = P(data) P(hypothesis data) P(data hypothesis) P(hypothesis) posterior likelihood prior N = Bandwidth =

7 3. Case studies: a) River exposure in Switzerland Gottschalk et al Modeled environmental concentrations of engineered nanomaterials (TiO2, ZnO, Ag, CNT, fullerenes) for different regions. Environmental Science and Technololgy 43, " Surface water Ort et al Model-Based Evaluation of Reduction Strategies for Micropollutants from Wastewater Treatment Plants in Complex River Networks. Environmental Science & Technology 43, " (EU mode values in tons/year) Go/schalk et al Engineered nanomaterials in rivers exposure scenarios for Switzerland at high spaxal and temporal resoluxon Environmental PolluXon 159: Receiving water bodies ENM emissions (6 000km influenced by 742 STP (covering >97% of populaxon)) Two scenarios: I) OpXmisXc scenario: Rapid engineered nanomaterial degradaxon/ deposixon between two sewage treatment plants II) ConservaXve scenario: No engineered nanomaterial degradaxon/ deposixon 7

8 Predicted concentrations (PECs) in Swiss rivers at water levels reached or exceeded in 95% of the time (modal ENM emission) Conserva-ve scenario A: 34% exceed (PNEC of 1 μg/l) Op-mis-c scenario "B: 23% exceedances" " PEC ranges for nano-tio2 based on daily flow rates measured between (two scenarios) Neal et al. (2010): Dissolved Ti average: 2.1 μg/l Ti (<0.45 μm) 8

9 Model uncertainty versus model variability Optimistic scenario Conservative scenario Geographical variation (at base flow) Factor (min-max) Factor (Q15%-Q85%) Temporal variation (location K) Factor (min-max) Factor (Q15%-Q85%) Scenario factor: Temporal variation (location S) Factor (min-max) Factor (Q15%-Q85%) Scenario factor: ENM emission uncertainty Factor (min-max) Factor (Q15%-Q85%) b) River exposure,glatt river 9

10 River exposure cont. Map of the catchment area of the Gla/ River and locaxons of the sewage treatment plants. Praetorius, A., Go/schalk, F., Scheringer, M., Hungerbuehler, K., Nowack, B., Work package 5: Exposure concentraxon models. Modelling nanoparxcle toxicity: principles, methods and novel approaches, ModNanoTox FP7 report. Results for different hetero aggregation (alpha) scenarios free TiO 2 NPs moving water mass concentration in ng/l TiO 2 NP + SPM moving water mass concentration in ng/l TiO 2 NP s sediment mass concentration in mg/kg sed Taken from: Praetorius, A., Go/schalk, F., Scheringer, M., Hungerbuehler, K., Nowack, B., Work package 5: Exposure concentraxon models. Modelling nanoparxcle toxicity: principles, methods and novel approaches, ModNanoTox FP7 report. S c stands for no heteroaggregaxon and no deposixon and the opxmisxc scenarios, S o for complete sedimentaxon before the next STP input. Methodologically this study represents a combinaxon of: Praetorius, A., Scheringer, M., Hungerbühler, K., Environ Sci Technol. 46, Go/schalk, F., Ort, C., Scholz, R.W., Nowack, B., Environmental PolluXon 159,

11 4. Overview available literature: Surface water See for sources : Go/schalk, F., Sun, T.Y., Nowack, B., Environmental concentraxons of engineered nanomaterials: Review of modeling and analyxcal studies. Environmental PolluXon 181, Sewage treatment plant effluents 11

12 Sewage treatment plant sludge Sediments (rivers) 12

13 Risk: most studied engineered nanomaterials (ENM) <0.0005% 18.7% 0% 1.1% 0.7% 39.7% 0% 0% 0% 0% " " Go/schalk F, & Nowack B. (2013). Engineered nanomaterials (ENM) in waters and soils: a risk quanxficaxon based on probabilisxc exposure and effect modelin. Environ. Toxicol. Chem. Thank you for the attention Contact informa-on Acknowledgment Empa/ETH/EAWAG/UNI Bremen: Bernd Nowack, Tobias Walser, Tobias Sonderer, Cristoph Ort, Elias Kost, R. Scholz, Roland Hischier, Sun Tian Yin, Nikolaus Bornhös Michael Steinfeldt, and others 13