Field and Laboratory Approaches for PFAS Mixture Toxicity Testing in Freshwater Fish

Date: Thursday, October 30, 2025, 12–1 p.m. ET

Abstract

Per- and polyfluoroalkyl substances (PFAS) are a diverse group of synthetic chemicals used in a wide range of industrial and consumer applications. Because of their widespread use and environmental persistence, PFAS have become pervasive contaminants in aquatic ecosystems globally, accumulating in surface water, ground water, sediments, and biota—often as complex mixtures. Currently, PFAS toxicity and ecological risk to freshwater ecosystems are not fully understood. Developing a comprehensive understanding of PFAS distribution, bioaccumulation, and toxicity in freshwater environments and species is critical for evaluating human exposure risk and ecosystem health. Our research in the Center for PFAS Research at Michigan State University investigates the impacts of PFAS mixtures in Great Lakes ecosystems and native fishes. This webinar will discuss the field and laboratory approaches we use to assess PFAS distribution, bioaccumulation, and toxicity, including environmental surveys, in situ studies, flow-through laboratory exposures, and dietary bioaccumulation studies. This research contributes to our understanding of PFAS impacts in freshwater ecosystems and can help inform future risk assessments.

The Presenters

Rachel R. LeadsPostdoctoral Research Associate, Michigan State University
Dr. Rachel Leads is an aquatic ecotoxicologist and postdoctoral research Associate in the Department of Fisheries and Wildlife and Center for PFAS Research at Michigan State University. She received her MS in marine biology from the College of Charleston and her PhD in biology from the University of North Texas. Her research characterizes the physiological mechanisms and ecological effects of contaminants and environmental stressors on marine and freshwater organisms. Currently, Dr. Leads studies the impacts of PFAS on native fish in the Great Lakes region. Overall, her work uses both field and laboratory assessments to understand the mechanisms and impacts of contaminant exposure on aquatic organisms across multiple levels of biological organization, from molecular to whole-organism responses.
Portrait of Brent Paulter
Brent G. PautlerChemistry Services Manager, SiREM
Brent received his PhD in environmental analytical chemistry in 2013 where he gained advanced technical experience in spectroscopy, chromatography, mass spectrometry, passive sampling, and chemistry informatics. Throughout his career, he has worked with scientists, engineers, and consultants, applying his expertise in chemistry and information technology to help them solve unique problems in the laboratory and the field. His role includes managing and advancing SiREM’s passive sampling portfolio, analytical testing services, and compound specific isotope analysis (CSIA) services.