ELUCIDATING THE ENVIRONMENTAL IMPACTS OF NANOPLASTICS

Millions of tons of plastic are discharged annually into ecosystems, endangering human health and biota. Plastic waste fragments into tiny particles known as nanoplastics (NPs), which result in cell death in aquatic organisms. This project will provide a mechanistic understanding of NP toxicity.

The overall objective of this PhD project is to elucidate the mechanisms underlying nanoplastic (NP) toxicity, by examining the extent to which membrane stress versus oxidative stress underlies the bactericidal activity of nanoscale plastics. Our studies will focus on bacterial cells, as bacteria form the base of trophic chains, and play key roles in nutrient cycling.

The objectives of this PhD research project are as follows:

- To develop new AFM experimental protocols to provide direct, real-time quantitative measurements of the interactions between bacterial cell membranes and NPs in aqueous media.

- To systematically investigate the effects of NP length scale and morphology, by synthesizing NPs with well- defined edge asperities. - To evaluate the relevance of oxidative pathways in NP-induced cell membrane damage.

- To develop computational tools (i.e., Matlab or Python scripts) for the high-throughput analysis of experimental AFM data.