| Summary: | Endocrine disrupting compounds (EDCs) can disrupt normal hormone signalling and production, and potentially contribute to a range of adverse effects on the environment and health. In vitro bioassay analysis was performed (mammalian reporter gene assays; RGAs) to assess the hormone receptor activity of common wastewater contaminants at environmentally relevant concentrations. The estrogenic enhancing capabilities of three parabens, 4-tert-octylphenol, carbamazepine and ketoconazole were identified; carbamazepine also disrupted glucocorticoid receptor (GR) transcriptional activity. In addition, RGAs were used, coupled with a high content analysis (HCA) assay, to investigate the potential for persistent organic pollutants (POPs) to induce stress responses via disruption of the GR. PFOS, PFDA, BDE-47 and p,p’-DDE altered mammalian stress responses. HCA was also used to investigate chemically defined POP mixture induced toxicity on a liver cell model and successfully detected early signs of cellular stress. While it is important to understand and classify the effects of contaminants, it is also crucial to gain information about their presence in the environment. To this end a UPLC MS/MS method was developed to monitor fifteen common aquatic contaminants. Screening of wastewater treatment work effluent revealed 10 of the 15 contaminants were still detectable after WWTW treatment. Furthermore anthropogenic pollution was evident in the rural catchment rivers. These catchments also have the phenomenon of unexplained static biological water recovery. The prevalence of EDC activity was investigated using an effect-directed bioassay analysis approach. Areas of concern were highlighted (androgen receptor and GR antagonism). Furthermore a statistically significant association between GR antagonism and average score per taxon (ASPT) values (a measure of biological water quality) was highlighted for one catchment. The use of novel techniques as HCA can help advance knowledge on mixture effects due to the ability to incorporate multiple parameters. The ability to detect pre-lethal signs of cellular stress is important for risk assessment. Furthermore, this thesis shows the importance of constant and updated screening methods of environmental waters. The inclusion of bioassays for screening water samples gives valuable information which targeted methods are unable to provide.
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