Boring crustaceans damage polystyrene floats under docks polluting marine waters with microplastic

► Boring sphaeromatid isopods destroy expanded polystyrene foam floats under docks. ► Boring damage was observed in multiple sites in Asia, Australia, Panama and the USA. ► An adult isopod expels thousands of microplastic particles when creating a burrow. ► Microplastics similar to these are consumed and may be toxic to fauna. ► Floats made of extruded polystyrene inhibit burrowing damage by isopods.