Occurrence of a Wide Range of Antibiotics, Estrogenic Hormones, and UV-Filters in Engineered and Natural Systems: Development of Analytical Methods and Investigation of Ecological Effects

摘要

Anthropogenic chemicals like pharmaceuticals, hormones, and personal care products have been widely used for decades and trace amounts of these compounds have been detected in different environmental compartments partially as traditional municipal wastewater treatment plants (WWTPs) are not designed to remove these specialized molecules. The appearance of these contaminants of emerging concern (CECs) in the environment has drawn increased attention due to the potential impacts on both human and ecological health. However, limited data are available on the environmental fate and ecotoxicity assessment of these CECs mainly attributed to the lack of effective and efficient analytical methods applied to complex environmental matrices. Moreover, considering the fact that over 4,000 pharmaceuticals, and even more personal care products, are currently being used, experimental risk assessment of all CECs in a timely manner is a tremendous task. Therefore, this dissertation focused on identification of priority CECs in complex environmental sample matrices and investigation of their associated ecotoxicological impacts through both field- and laboratory-based exposure studies. Antibiotics, estrogenic hormones, and organic UV-filters were proposed as priority CECs due to their biological impacts with respect to antimicrobial resistance and endocrine disruption, and several advanced analytical methods and effective bioassay protocols were developed for their determination in different environmental samples. The concentrations of over 50 target CECs were measured in both engineering (WWTPs) and natural (Chesapeake Bay) environmental systems including wastewater, wastewater-impacted surface water, estuary water, sediment, and invertebrate organisms. The bioaccumulation and effects of CECs was also investigated via a laboratory-scale chronic exposure study in red swamp crayfish (Procambarus clarkii) at two environmentally-relevant concentrations. Results from this dissertation highlighted the ubiquitous presence of CECs in the environment, the first identification of fleroxacin and moxifloxacin antibiotics in United States wastewater, the first UV-filters in crayfish (Orconectes virilis) and oysters (Crassostrea virginica), and the urgent need for integrated chemical and biological protocols to better understand the toxicity of complex mixtures of CECs at environmentally-relevant conditions. Overall, the comprehensive findings resulting from the interdisciplinary approaches employed in this dissertation provided a deeper understanding of the occurrence, fate, and impact of some of the most important CECs in the environment.