Comments on marine litter in oceans, seas and beaches: Characteristics and impacts

Abstract Marine litter is observed along shorelines, pelagic, benthic marine and lake systems all around the globe. On beaches, litter creates aesthetic and related economic problems because a clean beach is one of the most important characteristics of a seaside resort required by visitors. Litter can reach the marine environment from marine or land activities but it is estimated that 80% originates from land-based sources. The marine-based sources of litter include all types of sea-going vessel and offshore installations, the most abundant plastic debris in the oceans being derelict (lost or improperly discarded) fishing gear. Most of marine litter is composed by plastics due to their greater durability and persistence, combined with plastic rising production and low rates of recovery. Special importance is linked to microplastics because their ubiquity, persistence, mechanical effects on biota and the ecosystem because of ingestion by organisms and their toxic potential. As plastics degrade they can release toxic chemicals initially incorporated during their manufacturing or persistent organic pollutants and heavy metals sorbed to their surfaces in the environment. Such toxins can disrupt endocrine functions and cause harmful reproductive and developmental effects in aquatic animals.