Grant: Discovery Launch Supplement

Aquatic ecosystems potentially contain many harmful Chemicals of Environmental Concern (CECs), released into the environment during manufacture and use. In this proposal, we define CECs as chemicals with the potential to adversely affect the environment and human health. This includes `emerging' chemicals, some which have recently appeared in the environment, or have been present with recently raised concerns. Many CECs are currently not included in routine monitoring programs and lack published health standards. Examples of CECs, include industrial chemicals, pharmaceuticals, personal care products, and many other unknown chemicals. Characterizing CECs presents a significant research challenge because they exist in complex environmental mixtures, which can vary spatio-temporarily, resulting in an infinite number of possible real-world combinations. Traditionally, the risk assessment of contaminants has depended on single chemicals or known priority substances, with extrapolations to closely-related compounds. However, since chemicals co-occur and act jointly, this approach can underestimate risk because it overlooks combined effects. Effect-based methods (EBMs) offer a mixture-based approach as they integrate chemical analysis with in vivo or in vitro toxicity-testing to identify and prioritize CECs driving adverse effects. Moreover, when combined with non-targeted (NTA) screening methods, unknown and suspected CECs can be identified using high-resolution mass spectral methods. My research program aims to advance our current knowledge on complex CECs in mixtures in order to improve environmental health risk assessment. In applying EBMs with tools such as passive samplers, and NTA methods, this proposal will expand our knowledge on CECs. We will approach CECs broadly, as well as, focus on aquatic pollution related events, i.e. toxic algal blooms and tire wear. Short-term objectives are to: [1] Characterize the distribution of CECs from point sources to the aquatic environment, [2] Investigate the role of CECs in harmful algal blooms, [3] Measure tire-derived contaminants in the environment and identify potential markers, and [4] Investigate the influence of surface water parameters on CECs mixtures. This program has the potential to provide insight into CECs in aquatic ecosystems, by identifying novel ecological stressors and source-specific toxicological markers driving deleterious effects in mixtures. Furthermore, our work will help support risk assessments and long-term plans to address water safety. My proposed program is also highly multidisciplinary and collaborative, and will present learning and training opportunities for highly qualified personnel across several fields, including analytical chemistry, biology, and environmental science.