Co-contaminant Transport: Nanoplastics as vectors for organic chemical contamination

Nanoplastics are plastic fragments less than 1000 nm and are a growing concern within the plastic pollution crisis. They have distinct properties that differ from bulk plastics because of their size, large surface area-to-volume ratio, and their potential to disrupt biological processes once ingested. These particles can be further transported at larger distances and can be carriers for other pollutants via the “Trojan Horse” mechanism. This co-contaminant transport and uptake raise a concern as pollutants bound to nanoplastics can have a larger effect than they would on their own.  Hence, understanding the role of nanoplastics as vectors for organic contaminants is crucial for formulating effective strategies to mitigate their adverse effects on aquatic organisms and human health. The Arlos Research Group evaluated the adsorption of two different-sized polystyrene nanoplastics (PSNPs) (500 and 20 nm) with various trace organic substances in four types of water matrices. The sorption of plant protection products (glyphosate, methyl parathion), an antidepressant (fluoxetine), a ubiquitous industrial chemical (perfluorooctanoic acid [PFOA]) and a polycyclic aromatic hydrocarbon (phenanthrene) to commercially available polystyrene PSNPs was measured via radiolabeled techniques. The impacts of pH changes, low and high amounts of natural organic matter (NOM), and tertiary-treated wastewater effluent (pre- and post-UV treatment) on sorption were further evaluated.