Work

Photochemical Transformations of Consumer Plastics Shape the Diversity of Microbial Communities and Functions in the Coastal Ocean

Year: 2025

Type: preprint

Abstract: Sunlight driven transformations of plastics to dissolved organic carbon (DOC) is an important fate for plastic pollution in the ocean; however, the impact on microbial communities, including their abilities to adapt and metabolize plastic photo-products, is less understood. In this study, we characterized the photoreactivity of four common single-use plastic materials—polyethylene (PE), polyethylene terephthalate (PET), polylactic acid (PLA), and polystyrene (PS). The aromatic polymers (PS and PET) were notably more photoreactive than the aliphatic polymers (PE and PLA). PET and PS were photodegraded into compositionally similar DOC, and coastal microbial communities readily and similarly adapted their structure and function to metabolize the PET and PS photo-products. Comparative metagenomic analysis revealed that the compositionally similar photo-products uniformly affected metabolism of aromatics and carboxylic acids. Collectively, our findings indicate that coastal marine microbes are genetically equipped to readily metabolize PET and PS photo-products, suggesting these degradation products are less likely to persist and that strategies to enhance photodegradation may prove effective at mitigating plastic pollution.

Source: ChemRxiv

DOI: 10.26434/chemrxiv-2025-dfq0j