Presenter: Ben K. Feldman
Group Members: Emily K. Miller
Faculty Sponsor: Baoshan Xing
School: UMass Amherst
Research Area: Chemistry and Materials Science
Session: Poster Session 5, 3:15 PM - 4:00 PM, Auditorium, A52
ABSTRACT
Heteroaggregation with naturally occurring substances plays a critical role in determining the transport, fate, and ecotoxicity of nanoplastics. In this study, we investigated how different exposure sequences of nanoplastics and minerals to natural organic matter (NOM) affect their subsequent heteroaggregation. Our results indicate that when minerals are pre-exposed to NOM, the extent of heteroaggregation is significantly enhanced compared to scenarios where nanoplastics are pre-exposed to NOM. At low NOM concentrations, the modulation of heteroaggregation is primarily driven by electrostatic interactions, hydrogen bonding, and charge-assisted hydrogen bonding. In contrast, at high NOM levels, steric hindrance becomes the dominant mechanism controlling heteroaggregation. Moreover, the presence of Ca²⁺ was found to play a pivotal role, particularly under NOM-rich conditions, by facilitating aggregation through Ca-bridging effects.RELATED ABSTRACTS