The marine realm is the largest ecosystem on our planet. However, to most people “the sea” is an infinite mass of water hidden from their direct view by its shimmering surface. If the fate and possible effect of plastic in the world’s oceans shall be addressed, or the effect of the marine environment on plastic, it is needed to know the framework of conditions that shape this ecosystem. This holds especially true for the development of substantiated testing schemes for the biodegradability of bio-based solid materials. A solid testing scheme for the marine environment does not exist yet. The aim of this deliverable is to provide the back-ground knowledge needed for the definition of an improved and substantiated testing scheme from literature and relevant existing standards. A collection and critical analysis of information on the subject needed to base the subsequent activities on a knowledge background, was executed.