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Temporal Records of Organic Contaminants in Lake Sediments, Their Bioconcentration and Effect on Daphnia Resting Eggs

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Temporal Records of Organic Contaminants in Lake Sediments, Their Bioconcentration and Effect on Daphnia Resting Eggs Eawag_08974 Diss. ETH No. 21354 Temporal records of organic contaminants in lake sediments, their bioconcentration and effect on Daphnia resting eggs A dissertation submitted to the ETH ZURICH for the degree of Doctor of Sciences presented by AUREA CECILIA HERNANDEZ RAMIREZ OTHER FORMATS: AUREA CECILIA CHIAIA-HERNANDEZ MSc. In Chemistry, Oregon State University born 7 August 1980 citizen of Mexico accepted on the recommendation of Prof. Dr. Juliane Hollender, examiner Prof. Dr. Bernhard Wehrli, co-examiner Prof. Dr. Lee Ferguson, co-examiner PD. Dr. Piet Spaak, co-examiner 2014 ii Contents Summary vii Zusammenfassung xi 1 Introduction 1 1.1 Eutrophication and Anthropogenic Induced Environmental Changes . 2 1.2 Organic Pollutants in Sediments . 2 1.3 Analytical Procedures for the Detection and Identification of Parent Com- pounds and Transformation Products . 4 1.4 Daphnia as a Model Organism . 5 1.5 Bioaccumulation and Effects of Organic Contaminants . 6 1.6 Objectives and Contents of the Thesis . 7 2 Screening of Lake Sediments for Emerging Contaminants by Liquid Chro- matography Atmospheric Pressure Photoionization and Electrospray Ion- ization Coupled to High Resolution Mass Spectrometry 15 2.1 Introduction . 16 2.2ExperimentalSection............................. 18 2.2.1 Standards and Reagents . 18 2.2.2 Sample Collection and Preservation . 18 2.2.3ExtractionofSediments........................ 19 2.2.4 Clean-up and Enrichment of Sediment Extracts . 19 iii 2.2.5 Liquid Chromatography Tandem High Resolution Mass Spectro- metricDetection............................ 20 2.2.6AccuracyandPrecision........................ 21 2.2.7 Limits of Detection and Quantification . 21 2.2.8 Suspect Screening of Further Contaminants and Transformation Products . 21 2.2.9ProtonAffinityData.......................... 22 2.3ResultsandDiscussion............................ 23 2.3.1MethodPerformance.......................... 23 2.3.2 Optimization and Advantages of APPI . 25 2.3.3 Target Screening of Organic Contaminants in Sediment Cores of LakeGreifensee............................ 27 2.3.4 Suspect Screening of Further Contaminants and Transformation products . 30 Supporting Information to Chapter 2 . 43 3 Suspect and Non-target Screening Approaches to Identify Records of Or- ganic Contaminants in Sediments 69 3.1 Introduction . 70 3.2ExperimentalSection............................. 72 3.2.1 Sample Collection and Preservation . 72 3.2.2 Extraction, Clean-up and Enrichment of Sediment Extracts . 73 3.2.3 Liquid Chromatography Tandem High Resolution Mass Spectro- metricDetection............................ 73 3.2.4 Suspect Screening of Further Contaminants and Transformation Products . 74 3.2.5 Non-target Screening of Further Contaminants . 75 3.3ResultsandDiscussion............................ 78 3.3.1 Target Screening of Organic Contaminants in Sediment Cores of Lake Lugano . 78 iv 3.3.2 Suspect Screening of Further Contaminants and Transformation Products . 78 3.3.3 Non-target Screening of Unknown Contaminants . 82 3.3.4InsightsandFutureResearch..................... 85 Supporting Information to Chapter 3 . 97 4 Bioconcentration of Organic Contaminants in Daphnia Resting Eggs 125 4.1 Introduction . 126 4.2ExperimentalSection.............................128 4.2.1 Sample Collection and Preservation . 128 4.2.2 Ephippia Exposure: Uptake and Depuration Kinetics . 128 4.2.3 Clean-up and Enrichment of Extracts . 130 4.2.4 Liquid Chromatography Tandem High Resolution Mass Spectro- metricDetection............................130 4.2.5BioconcentrationFactor(BCF)....................131 4.2.6 Predicting Concentrations in Ephippia in the Environment . 133 4.3ResultsandDiscussion............................134 4.3.1SedimentAnalysis...........................134 4.3.2 Uptake and Depuration Kinetics . 134 4.3.3 Ephippia Bioconcentration Factor (BCF) . 135 4.3.4 Estimated Concentrations in Ephippia in the Environment . 140 Supporting Information to Chapter 4 . 149 5 Environmental Organic Contaminants Influence Hatching from Daphnia Rest- ing Eggs and hatchling survival 163 5.1 Introduction . 164 5.2 Material and Methods . 167 5.2.1 Ephippia Collection and Preparation . 167 5.2.2 Standards and Reagents . 168 5.2.3HatchingExperiment..........................168 v 5.2.4 Ephippia and Egg Counting . 170 5.2.5StatisticalAnalysis...........................171 5.3ResultsandDiscussion............................172 5.3.1HatchingSuccess...........................173 5.3.2HatchlingMortality...........................176 5.3.3Implications...............................178 Supporting Information to Chapter 5 . 191 6 Conclusion & Outlook 193 6.1Conclusion...................................194 6.2Outlook.....................................196 Acknowledgements 203 Curriculum vitae 205 vi Summary vii viii Summary Emerging contaminants are important since they can have complex effects on ecosys- tems. However, the fate and occurrence of many organic contaminants could not be assessed in the past due to the lack of technology available. Measurements of emerg- ing contaminants such as pharmaceutical and personal care products started in the 1990s, thus the exposure before this time is not well studied. Sediment cores have been shown to be useful to reconstruct environmental changes over time, providing historic records of natural events, changes in ecosystems, and climate. Therefore, sediments could be suitable to reconstruct the environmental con- tamination to provide records of anthropogenic impact. Chemicals can enter natural waters via wastewater treatment plant effluents, urban and industrial sewage, runoff, spray drift and leaching from agricultural areas and sorb to sediments. As a result, sediments are excellent archives of environmental contaminants if the chemicals persist over time since they can act as integrators of many inputs within a catchment. Until now, sediments have been mainly used to characterize the contam- ination of legacy compounds like polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs) with highly hydrophobic characteristics. Therefore, the knowl- edge of long-term contamination with medium polar contaminants is not well explored. A multiresidue method was developed for the screening of more than 200 emerging contaminants and their transformation products with a broad range of physicochemi- cal properties in lake sediments. Sediment cores were extracted by pressurized liquid extraction and liquid-liquid partitioning, followed by liquid chromatography high reso- lution tandem mass spectrometry (HRMS/MS) using electrospray ionization (ESI) and atmospheric pressure photoionization (APPI). Next, the spatial and temporal distribu- tion of medium polar organic contaminants from two lakes in Switzerland were studied to understand the fate of less hydrophobic organic contaminants. The results show that biocides, musk fragrances, and other personal care products were the most frequently detected compounds, whereas none of the targeted pharmaceuticals were found. The concentrations trend of many urban contaminants originating from wastewater corre- late temporally with the phosphorus inputs into the lake, which is a proxy for treatment efficiency of a wastewater treatment plant. Highest concentrations are observed at the beginning of the 1980s followed by rapid decline on Lake Greifensee while increasing concentrations in the late 1970s followed by a starting decline in concentrations starting in the 1990s is observed on Lake Lugano. The use of HRMS enabled a retrospective analysis of the full-scan data acquisition al- lowing the detection of suspect compounds like quaternary ammonium surfactants, the biocide triclocarban, the identification of the transformation products of triclosan and Summary ix triclocarban, and furthermore the identification of different biocides and disinfectants in use in Switzerland. In addition, the use of HRMS/MS, together with computer assisted molecular formula generation and in silico fragmentation, enabled the identification of non-targeted compounds such as the mothproofing flucofuron and the disinfectant hex- achlorophene. The compounds found can have complex effects on sediment ecosystems and consti- tute a primary source of exposure for benthic organisms. The effect of these organic contaminants was assessed by experimental studies measuring their bioconcentration factors (BCF) in Daphnia resting eggs (ephippia). The results show that personal care products, pesticides, pharmaceuticals, and biocides found in the sediments can bioac- cumulate in ephippia. Furthermore, a model was developed to predict bioaccumulation of other compounds as a function of hydrophobicity. Analysis of organic contaminants in ephippia extracted from sediment cores is not possible due to the small number of ephippia available in the sediment extraction and the amount needed for the chemi- cal analysis. Therefore, internal concentrations in ephippia in the environment were predicted based on sediment concentrations using the equilibrium partitioning model (EqP) and calculated BCFs. Estimated internal concentration values were obtained with triclocarban having the highest internal concentrations, followed by tonalide and triclosan. The outcomes show that contaminants can be taken up by ephippia from the water column or sediments. Additional experiments were performed to test ephippia hatching abilities and fitness after exposure to organic contaminants resulting in high mortality and deformation. The exposure concentrations were selected according
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