Following the European Commission’s definition, "marine litter consists of items that have been deliberately discarded, unintentionally lost, or transported by winds and rivers, into the sea and on beaches. It mainly consists of plastics, wood, metals, glass, rubber, clothing and paper". Marine debris originates from a variety of sources. Shipping and fishing activities are the predominant sea based, ineffectively managed landfills as well as public littering the main land based sources. Marine litter can pose a threat to living organisms, especially due to ingestion or entanglement.
Currently, there is no international standard available, which appropriately describes the biodegradation of plastics in the marine environment. However, several standardisation projects are in progress at ISO and ASTM level. Furthermore, the European project OPEN BIO addresses the marine biodegradation of biobased products.