Photochemical dissolution of buoyant microplastics to dissolved organic carbon: Rates and microbial impacts.

•Sunlight can remove microplastics from the sea surface.•The type of plastic influences how rapidly microplastics photo-degrade.•Microplastics dissolve at the sea surface due to sunlight-driven photochemistry.•Dissolved organic carbon is produced as microplastics photo-dissolve in sunlight.•Photo-produced dissolved organic carbon impacts marine bacteria.