The Application of Mass Spectrometry in Environmental

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The Application of Mass Spectrometry in Environmental THE APPLICATION OF MASS SPECTROMETRY IN ENVIRONMENTAL CHEMISTRY: INVESTIGATING BIOLOGICAL CYCLING OF ARSENIC, MERCURY AND GLYCINE BETAINE IN AQUATIC ECOSYSTEMS by Abdullah Mohammed Alowaifeer A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Ecology and Environmental Sciences MONTANA STATE UNIVERSITY Bozeman, Montana May 2019 ©COPYRIGHT by Abdullah Mohammed Alowaifeer 2019 All Rights Reserved ii DEDICATION To my parents and siblings. Without your prayers and support I would not be who I am today. iii ACKNOWLEDGEMENTS I would like to express my special appreciation to my advisor, Dr. Timothy R. McDermott, for his support and patience throughout my time in graduate school. Your guidance has been essential in my success as a student and will continue to benefit me throughout my career. I would also wish to express my gratitude to my co-advisor, Dr. Brian Bothner, you have been a tremendous mentor for me. Thank you for your encouragement and support. I would also like to thank my graduate committee for their continuous guidance and advice. I would like to thank members of the McDermott lab, Bothner lab, Mass Spectrometry facility and the land resources and environmental sciences department for all their help. Finally, I am very grateful to the Saudi Food and Drug Authority for giving me the opportunity to pursue my PhD and for funding my research. Thank you for believing in me. iv TABLE OF CONTENTS 1. INTRODUCTION .................................................................................................... 1 Arsenic in Aquatic Environments ............................................................................ 1 Oxidation/Reduction ................................................................................... 2 Methylation/Demethylation ........................................................................ 3 Thioarsenicals ............................................................................................. 5 Arsenic Resistance and Toxicity ................................................................. 6 Sediment Water Exchange .......................................................................... 7 Arsenic in Phytoplankton ............................................................................ 9 Arsenic in Zooplankton............................................................................. 13 Bioaccumulation and Biomagnification in Higher Trophic Animals ....................................................................................... 15 Mercury in Aquatic Environments ......................................................................... 20 Oxidation/Reduction ................................................................................. 21 Methylation/Demethylation ...................................................................... 22 Mercury Toxicity ...................................................................................... 23 Mercury Cycling ....................................................................................... 26 Mercury in Planktonic Organisms ............................................................ 29 Mercury in Aquatic Animals .................................................................... 32 Glycine Betaine in Aquatic Environments ............................................................. 39 Glycine Betaine Synthesis ........................................................................ 40 Betaine Lipids ........................................................................................... 42 Fate of Glycine Betaine ............................................................................ 44 Methylated Amines in Aquatic Environments ........................................................ 45 Research Goals ....................................................................................................... 48 References .............................................................................................................. 55 2. METHOD AND METHOD DEVELOPMENT ...................................................... 75 Sample Preparation ............................................................................................... 75 Total Metal and Metalloids Extraction ..................................................... 75 Arsenic Species Extraction ....................................................................... 75 Labeling Amines in Water with Dansly Chloride..................................... 76 Labeling Trimethylamine in Water with Ethylbromoacetate ................... 77 v TABLE OF CONTENTS – CONTINUED Mass Spectrometer Analysis .................................................................................. 77 Analysis of Total Metal and Metalloids by ICP-MS ................................ 77 Arsenic Species Analysis by IC- ICP-MS ................................................ 78 Analysis of MMA and DMA by LC-MS .................................................. 78 Analysis of TMA by LC-MS .................................................................... 79 Analysis of Glycine Betaine in Water by LC-MS .................................... 80 Analysis of Water-Soluble Methane by GC ............................................. 80 References ............................................................................................................. 84 3. BIOLOGICAL CYCLING OF ARSENIC AND MERCURY IN YELLOWSTONE LAKE ................................................................................ 85 Contribution of Authors and Co-Authors .............................................................. 86 Manuscript Information Page ............................................................................... 87 Abstract ................................................................................................................. 87 Introduction ........................................................................................................... 88 Materials and Methods .......................................................................................... 90 Sampling Location and Procedure ............................................................ 90 Analysis for Total Mercury and Arsenic .................................................. 91 Analysis for Arsenic Species .................................................................... 91 Results ................................................................................................................... 93 Total Mercury .............................................................................................. 93 Planktonic Arsenic ...................................................................................... 94 Arsenic in Cutthroat and Lake Trout .......................................................... 95 Discussion ............................................................................................................. 97 References ........................................................................................................... 108 4. EXAMING THE ROLE OF PHOTOAUTOTROPHS CONTRIBUTING TO GLYCINE BETAINE, METHYLATED AMINES AND METHANE IN OXIC RIVER WATERS .................................. 110 Contribution of Authors and Co-Authors ............................................................. 111 Manuscript Information Page ............................................................................... 112 Abstract ................................................................................................................ 112 Introduction .......................................................................................................... 113 vi TABLE OF CONTENTS – CONTINUED Materials and Methods ......................................................................................... 115 Sampling Location and Procedure .......................................................... 115 Labeling and Sample Preparation ........................................................... 117 Analysis for Methylated Amines and Glycine Betaine........................... 118 Analysis for Water-Soluble Methane...................................................... 118 Lake Water Microbial Activity ............................................................... 120 Results ................................................................................................................. 121 Discussion ........................................................................................................... 122 References ........................................................................................................... 136 5. CONCLUDING REMARKS ............................................................................... 138 6. REFERENCES CITED ........................................................................................ 142 vii LIST OF TABLES Table Page 4.1 Physical and chemical measurments collected from tthe Madison River at different sampling dates in 2018 .................................. 129 4.2 Physical and chemical measurments collected from tthe Gallatin River at different sampling dates in 2018 ................................... 129 4.3 Physical and chemical measurments collected from tthe Yellowstone River at different sampling dates in 2018 ............................ 130 viii LIST OF FIGURES Figure Page 1.1 The two common inorganic arsenic species ...................................................
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