As network of early stage researchers in biotechnology connected to greener approaches, we would like to bring also to our attention a current global issue. The harmful potential of the plastics in Earth landscape is a hot discussed topic at the moment. Similarly to many anthropogenic impacts on nature, and despite widespread recognition of the worry, this is potentially still growing and even if stopped immediately will persist for centuries. The major amount of plastics released into the environment is the result of inappropriate waste management and disreputable human behavior (e.g. abandoning waste improperly). ^[1]

Do we really need to use the amount of plastics we are using everyday? The answer is probably no. We are just all used to the daily utilization of plastic tools, many of which are for single use. Until a massive plan is not applied in each country prioritizing the sustainability (e.g. fully commercialization of bio-degradable plastics and/or intensive proper waste management with a view to the circular economy), at least littering must be avoided.

Massive plastic accumulation is taking place on different landscapes, occurring heavily on coastlines, at the sea surface, on the sea floor, and in Arctic sea ice. ^{[2, 3, 4]} This has been slowly begun since approximately 1950 when its production started to be intensive. Mainly due to its general high strength and the massive production, the long degradation time of used plastic causes a volumetric accumulation in the environment which increases time by time. These polymers can be fragmented in the environment as a consequence of prolonged exposure to UV light and physical abrasion. This is particularly evident on shorelines where photo-degradation and abrasion through wave action increase their fragmentation. The range of plastic debris sizes can broadly be divided into mega (> 100 mm diameter), macro (> 20 mm), meso (5–20 mm), and micro (< 5mm) debris. ^[1]

The variations of pelagic micro-plastic abundance in the Pacific Ocean from 1957 to 2066 were recently shown. This study was based on a combination of numerical modeling supported on removal processes on a 3-year timescale and transoceanic surveys conducted from Antarctica to Japan. The results suggested that the weight concentrations of pelagic micro-plastics around the subtropical convergence zone would increase approximately twofold by 2030 and fourfold by 2060 from the present condition. ^[5] A major ocean plastic accumulation zone is formed in subtropical waters between California and Hawaii: The Great Pacific Garbage Patch. This is the largest of the five offshore plastic accumulation zones in the world’s oceans. ^[6] The mass of the plastic was estimated to be approximately 80 thousand tonnes. Having a more practical idea of the number, this value is similar to the weight of 500 Jumbo Jets. Due to seasonal and interannual variabilities of winds and currents, the location and shape are constantly changing. Only floating objects that are predominantly influenced by currents and less by winds were likely to remain within the patch. The vast majority of plastics retrieved were made of rigid or hard polyethylene or polypropylene, or derelict fishing gear. A recent model, calibrated with data from multi-vessel and aircraft surveys, predicted at least 79 thousand tonnes of ocean plastic are floating inside an area of 1.6 million km². Over three-quarters of the mass was carried by debris larger than 5 cm and at least 46% was comprised of fishing nets. 1.8 trillion micro-plastics pieces are floating in the area. The ocean plastic pollution within the Great Pacific Garbage Patch is increasing exponentially and at a faster rate than in surrounding waters. ^[7]

In a recent “Green paper on a European strategy on plastic waste in the environment”, the European Commission addresses the issue as part of a wider review of its waste legislation. ^[8] This document focuses on potential mitigation strategies for plastic litter at the source and also expresses particular concern about their hazardous potential. ^[9]. Micro-plastics are ingested by hightrophic-level taxa, such as birds and marine mammals. A comprehensive assessment of the whole digestive tracts of 50 individuals from 10 species was recently investigated at the British coast. Micro-plastics were ubiquitous with particles detected in every animals examined. A relatively low number per animal (mean micro-plastics = 5.5) was observed. Stomachs contained a greater number than intestines indicating a potential site of temporary retention. 84% of particles were fibers while the remaining 16% was fragments. Nylon was the most prevalent polymer type. A possible relationship was found between the cause of death category and micro-plastic abundance, indicating that animals that died due to infectious diseases had a slightly higher number of particles than those that died of trauma and other causes of mortality ^[10]. The potential toxicity of the chemicals mix is not the only cause for concern, also microorganisms developing biofilms on such particles. Opportunistic pathogens like specific members of the genus Vibrio were found to dominate plastic particles. Therefore, micro-plastics can act as a vector for pathogens influencing the hygienic water quality. This interaction is still poorly understood and needs to be further investigated. ^[9]

Others interesting samplings were recently done through surface trawls in oceanic surface waters of the Antarctic Peninsula. Hard and flexible fragments, spheres and lines were found. Mean debris concentration was estimated at 1,794 items ∙ km⁻². No statistical difference was found between the amount of meso-plastics (46%) and micro-plastics (54%). Their composition had mostly of polyurethane, polyamide, and polyethylene. Sources of plastics in Antarctica can be diverse, including direct sources via disposal or inadequate management of waste produced by ships and research stations. Indirect sources such as transport by marine currents are carrying plastics from distant areas located at lower latitudes. Paint fragments were present at all sampling stations and were approximately 30 times more abundant than plastics. ^[11]

Population size and the quality of waste management system largely determine which countries contribute the greatest mass of uncaptured waste available to become plastic marine debris. China, Indonesia, Philippines, Vietnam, and Sri Lanka are the countries with highest % of total mismanaged plastic waste calculated in a study by 2015. ^[2] Especially in marine basins, plastic fragments are widespread and potentially source of negative effects also on terrestrial food chain. Data from freshwater ecosystems are scarce, only few investigations providing evidence for the presence of micro-plastics in rivers and lakes are reported. ^{[11, 12]}

Schools and voluntary organizations (e.g. The Ocean Cleanup, Seabin Project, 4Ocean) have made annual coastal and ocean surface collections of stranded plastics. This is an important educational issue for future generations.