Plastic is present everywhere around us – its durability, low cost, light weight and easily modified shape and properties has led to almost exponential increase in production since its large-scale manufacturing started in 1950s. Nowadays the global annual production of plastics exceeds 311 million tons and it is expected to rise year after year. Plastic is a synthetic material consisting of polymers, which form the basic structure of plastic. This structure can be modified to fulfil different needs by using additives that for example improve the flexibility or strength of the material. The wide variety of different plastics have their unique properties which make them suitable for different applications, e.g. packaging or insulation.
Marine litter includes all anthropogenic material that has been entered the marine environment by intentional or unintentional actions of human beings. The composition of marine litter varies between locations, but usually most of the litter consists of plastic. Plastic litter is considered as a long-lasting threat to the environment, since it is not easily degraded: UV-radiation and thermal energy induces weathering and causes plastic to fragment into small pieces called microplastics. Without further biodegradation carried out by micro-organisms, both large plastic litter and fragmented pieces are assumed to persist in the marine environment even hundreds of years.