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Establishing Realistic Test Settings in Aquatic Ecotoxicological Risk Assessments Mona Katharina Feiner

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Establishing Realistic Test Settings in Aquatic Ecotoxicological Risk Assessments Mona Katharina Feiner TECHNISCHE UNIVERSITÄT MÜNCHEN Lehrstuhl für Aquatische Systembiologie Establishing realistic test settings in aquatic ecotoxicological risk assessments Mona Katharina Feiner Vollständiger Abdruck der von der Fakultät Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt der Technischen Universität München zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften genehmigten Dissertation. Vorsitzender: Prof. Dr. Johannes Kollmann Prüfer der Dissertation: 1. Prof. Dr. Jürgen Geist 2. Prof. Dr. Christian Laforsch Die Dissertation wurde am 23.03.2017 bei der Technischen Universität München eingereicht und durch die Fakultät Wissenschaftszentrum Weihenstephan für Ernährung, Landnutzung und Umwelt am 28.09.2017 angenommen. Table of Content LIST OF TABLES ................................................................................................................................... 5 LIST OF FIGURES .................................................................................................................................. 6 PREFACE ................................................................................................................................................ 8 ABSTRACT ............................................................................................................................................. 9 ZUSAMMENFASSUNG .......................................................................................................................... 11 1. GENERAL INTRODUCTION ........................................................................................ 13 1.1. Ecotoxicological risk assessments ............................................................... 13 1.2. Standard ecotoxicological investigations ...................................................... 14 1.3. Deficiencies in current test settings .............................................................. 20 1.4. Objectives .................................................................................................... 25 2. SUBLETHAL EFFECTS OF THE BETA-BLOCKER SOTALOL AT ENVIRONMENTALLY RELEVANT CONCENTRATIONS ON THE NEW ZEALAND MUDSNAIL POTAMOPYRGUS ANTIPODARUM ....................................................................................................... 26 2.1. Abstract ........................................................................................................ 27 2.2. Introduction .................................................................................................. 28 2.3. Material and Methods ................................................................................... 30 2.3.1. Pharmaceutical preparation and chemical fate ..................................... 30 2.3.2. Test organisms and test setup .............................................................. 31 2.3.3. Growth, reproduction, mortality, and offspring size ............................... 32 2.3.4. Statistical analyses ............................................................................... 33 2.4. Results ......................................................................................................... 34 2.4.1. Chemical fate of SOT ........................................................................... 34 2.4.2. Reproduction, growth, and mortality ..................................................... 34 2.4.3. Offspring size ........................................................................................ 36 2.5. Discussion .................................................................................................... 38 3. INCREASED RO CONCENTRATE TOXICITY FOLLOWING APPLICATION OF ANTISCALANTS – ACUTE TOXICITY TESTS WITH THE AMPHIPODS GAMMARUS PULEX AND GAMMARUS ROESELI ................................................................................................................. 41 3.1. Abstract ........................................................................................................ 42 3.2. Introduction .................................................................................................. 43 3.3. Material and Methods ................................................................................... 45 3.3.1. Test organisms ..................................................................................... 45 3.3.2. Antiscalants, concentrate, and test-medium ......................................... 45 3.3.3. Acute toxicity test .................................................................................. 46 3.3.4. Statistical analyses ............................................................................... 47 3.4. Results and Discussion ................................................................................ 48 4. MINIATURE CIRCULATORY SYSTEM (MCS): A NEW EXPOSURE SYSTEM FOR ECOTOXICOLOGICAL EFFECT ASSESSMENTS IN RIVERINE ORGANISMS ....................... 53 4.1. Abstract ........................................................................................................ 54 4.2. Introduction .................................................................................................. 55 4.3. Material and Methods ................................................................................... 59 4.3.1. Miniature Circulatory System (MCS) .................................................... 59 4.3.2. Reverse osmosis concentrate .............................................................. 61 4.3.3. Salmonid egg development .................................................................. 61 4.3.4. Gammarus roeseli test condition improvement..................................... 62 4.3.5. Gammarus roeseli copper toxicity test .................................................. 62 4.3.6. Statistical analyses ............................................................................... 63 4.4. Results ......................................................................................................... 65 4.4.1. Miniature circulatory system performance ............................................ 65 4.4.2. Salmonid egg development .................................................................. 65 4.4.3. Gammarus roeseli test system improvement........................................ 66 4.4.4. Gammarus roeseli copper toxicity test .................................................. 67 4.5. Discussion .................................................................................................... 70 5. GENERAL DISCUSSION ............................................................................................ 73 5.1. Appropriate test durations in long-term investigations ................................. 74 5.2. Conditions of substances entering the environment ..................................... 76 5.3. New exposure systems for non-standard stream-dwelling test species ....... 78 6. OUTLOOK .............................................................................................................. 80 7. REFERENCES ......................................................................................................... 81 8. LIST OF PUBLICATIONS INCLUDED IN THIS THESIS ...................................................... 97 9. ACKNOWLEDGEMENT .............................................................................................. 98 LIST OF TABLES Table 1-1. Available test guidelines from ISO, OECD and US EPA that incorporate freshwater species and the respective test durations and endpoints ......................... 16 Table 1-2. Mean effect concentrations (EC50) for immobility in Daphnia magna of the five most frequently detected pharmaceutical compounds worldwide (based on number of observations; Hughes et al. 2013) and their respective maximal measured environmental concentration (MECmax.) .................................................................... 24 Table 2-1. Concentrations of sotalol measured in surface waters (Rohweder 2003) and test concentrations used in this study (µg/L) ...................................................... 30 Table 2-2. Mean sotalol concentrations (± standard deviation) at test initiation, after 48, 96, and 168 h ....................................................................................................... 34 Table 2-3. Results of the simple linear regression for neonate sizes as top-view shell area over time ............................................................................................................ 36 Table 3-1. Mean concentrations of main solutes in reverse osmosis concentrate derived from the pilot station (± standard deviation). The station was run with feed at a rate of 40 L/s and an antiscalant metering of 1.5 g/m³. The recovery rate was 80% .................................................................................................................................. 46 Table 3-2. Range of mean O2-saturation (%) in the acute toxicity tests with the three different concentrates at the beginning and after 96 and 168h. Measurements were conducted in the control treatment and the highest test concentration ...................... 47 Table 3-3. EC50-values determined by probit-analyses in the acute toxicity tests with FF8 and RPI, respectively, for G. pulex and G. roeseli after 96 and 168 h ................ 50 Table 4-1. Physicochemical parameters in the MCS in the experiments with S. trutta and G. roeseli. Numbers are overall range (conductivity in S. trutta-experiment) and overall means ± standard
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