Title: Understanding environmental reactions of PFAS and other contaminants for a more sustainable world
Abstract:
Harmful chemical contaminants are found in nearly every corner of the environment, affecting humans, wildlife, and drinking water. Ideally, all human-made chemicals would degrade safely after use, but unfortunately, many either persist themselves or transform into persistent and toxic products. Understanding environmental reactions is required to assess the lifecycle impact of a chemical and to determine why certain chemicals degrade while others do not. In this talk, I will focus on our efforts to identify reactive sources of trifluoroacetic acid (TFA) in the environment, a contaminant that is extremely persistent and increasing in environmental concentration. We are investigating how aquatic photochemistry reactions of aryl-CF3 contaminants, including pesticides and pharmaceuticals, can form TFA instead of complete mineralizion to fluoride. Mechanistic insights were gained by testing a scope of aryl-CF3 with different substituents, and the use of stable isotope labelling with high resolution mass spectrometry to track transformation product formation. I will also discuss our work understanding the fate of rubber additives and oil constituents in aquatic ecosystems. Together, this work aims to minimize exposure to harmful chemicals and inform design for degradation for a healthier, more sustainable society.
Bio:
Dr. Shira Joudan is an Assistant Professor in the Department of Chemistry at the University of Alberta. The Joudan Lab investigates how chemical and physical processes govern the environmental fate and transport of organic contaminants, and the resulting human and ecological exposure. Ultimately, their research helps inform policy and hopefully helps to design chemicals that provide functionality without environmental harm. Shira grew up in Winnipeg, obtained her BSc from Carleton University (2013), her PhD from the University of Toronto (2020), and held a postdoctoral research position at York University in Toronto (2022). In 2025, she was recognized as a Talented 12 by Chemistry & Engineering News. Since 2022 she has been a regular columnist for Nature Chemistry writing about experiences in academia.