Microbial interactions with microplastics: Insights into the plastic carbon cycle in the ocean

Once entering the ocean, plastics undergo biotic and abiotic degradation to smaller particles (microplastics, MPs) and dissolved organic carbon (DOC), contributing to the pools of particulate organic carbon (POC) and DOC, respectively. We conducted laboratory experiments on the natural microbial assembles of coastal and offshore water samples from the Gulf of Maine to investigate (i) potential rates of microbial degradation of plastic-derived DOC, and (ii) the role of phytoplankton aggregates in vertical sinking of MPs (plastic POC).