University Archives

Plastic pollution has emerged as one of the most pervasive threats to aquatic ecosystems, with microplastics (<5 mm) and nanoplastics (<1 µm) infiltrating freshwater and marine environments worldwide. Microplastics are plastic particles that persist in aquatic environments and can accumulate in the tissues of organisms. Nanoplastics are even smaller particles that can cross biological membranes and cause intracellular damage. Because fish rely extensively on olfactory cues to locate food, identify conspecifics, and detect predators, their sensory systems represent a critical but vulnerable target of plastic exposure. To investigate these impacts, we exposed male and female fathead minnows to polystyrene MPs (30 µm) and NPs (0.5 µm) for 28 days at concentrations of 0 mg/L (control) and 1 mg/L. Motion tracking analysis will be conducted to quantify avoidance and preference responses to ecologically relevant odorants including L-alanine (food), taurocholic acid (social), and conspecific alarm cue. Given their smaller size we do anticipate that the fathead minnows exposed to nanoplastics will experience more severe olfactory deficits compared to those exposed to microplastics.  By understanding the impacts of plastic exposure on the olfactory system and impairments in olfactory-driven behavior, this study will provide insights into how micro- and nanoplastics may jeopardize fish survival.