Supplement for Role of Environmental Weathering and Gastrointestinal Digestion on the Bioavailability and Toxicity of Microplastic and Cadmium Mixtures - Project Summary of Diversity Supplement
In this supplement, the postdoctoral fellow candidate Dr. Justin Scott will carry out a project with the overall
goal of understanding the sorption of organic compounds onto weathered MPs and nanoplastics (NPs), and
MPs and NPs bioaccumulation and toxicity in fish (RTgutGC) and human (Caco2) intestinal cell lines. This will
allow us to better understand their transformation and fate after ingestion and determine exposure risk and
potential adverse effects. Justin will complement his toxicological training by learning advanced spectroscopy
and environmental chemistry methodologies under the supervision of Dr. Jorge Gonzalez Estrella. Through the
incorporation of analytical techniques such as dynamic light scattering (DLS), zeta potential, Fourier transform
infrared (FTIR), scanning electron microscopy (SEM), and pyrolysis gas chromatography mass
spectrophotometry (py-GC-MS) we will gain a better understanding of MP and NPs reactivity and adverse
effects. Importantly, the reactivity of specific weathered (i.e., UV aged and oxidized) MPs/NPs types (i.e.,
polyethylene, polyvinyl chloride, and polypropylene) with specific organic chemical mixtures (i.e., lindane,
dichlorodiphenyldichloroethylene (DDE), and azoxystrobin) will be determined. In addition, the adverse effect
of MPs/NPs alone or in co-exposure with organics will be evaluated using a physiologically relevant exposure
system which includes in vitro digestion and intestinal cells lines. We hypothesize that environmental
weathering of MPs and NPs will increase sorption of organic chemical mixtures onto them, which will increase
the contaminant uptake by the intestinal epithelium. Moreover, gastrointestinal and digestive processes will
allow desorption of chemicals from MPs and NPs and an increase in bioaccumulation and cytotoxicity. Aim .1
Evaluate the reactivity of weathered MP and NP with organic chemical mixtures in exposure media; Aim 2:
Evaluate the Fate of organic chemical mixtures and MPs/NPs in the exposure system; and Aim 3: Evaluate the
role of gastrointestinal digestion processes on MPs/NPs reactivity with organic chemicals and effect in
intestinal cells.
