Solving the plastic problem: From cradle to grave, to reincarnation

Abstract

Plastic packaging accounts for 36% of all plastics made, but amounts to 47% of all plastic waste; 90% of all plastic items are used once and then discarded, which corresponds to around 50% of the total mass of plastics manufactured. Evidence for the ubiquity of microplastic pollution is accumulating rapidly, and wherever such material is sought, it seems to be found. Thus, microplastics have been identified in Arctic ice, the air, food and drinking water, soils, rivers, aquifers, remote maintain regions, glaciers, the oceans and ocean sediments, including waters and deep sea sediments around Antarctica, and within the deepest marine trenches of the Earth. They have also been detected in the bodies of animals, including humans, and as being passed along the hierarchy of food chains, up to marine top predators. Evidence has also been presented that microplastics are able to cross different life stages of mosquito that use different habitats -larva (feeding) to pupa (non-feeding) to adult terrestrial (flying) -and therefore can be spread from aquatic systems by flying insects. The so-called 'missing plastic problem' appears to be, in part, due to limitations in sampling methods, that is, many of the very small microplastic particles may simply escape capture in the trawl nets that are typically employed to collect them, but have been evidenced in grab-sampling experiments. Moreover, it is simply not possible to measure entirely through the vast, oceanic volumes of the oceans. It can, however, be concluded with some confidence that the majority of the plastic is not located at the sea surface, and indeed, several different sinks have been proposed for microplastics, including the sea floor and sediments, the ocean column itself, ice sheets, glaciers and soils. The treatment of land with sewage sludge is also thought to make a significant contribution of microplastics to soil. A substantial amount of airborne microparticulate pollution is created by the abrasion of tyres on road surfaces (and other 'non-exhaust' sources), meaning that even electric vehicles are not 'clean' in this regard, despite their elimination of tailpipe PM 2.5 and PM 10 emissions. The emergence of nanoplastics in the environment poses a new set of potential threats, although any impacts on human health are not yet known, save, as indicated from model studies. While improved design, manufacture, collection, reuse, repurposing and reprocessing/recycling of plastic items are necessary, overwhelmingly, a Article Rhodes 219 curbing in the use of plastic materials in the first place is demanded, particularly from single-use packaging. However, plastic pollution is just one element in the overall matrix of a changing climate ('the world's woes') and must be addressed as part of an integrated consideration of how we use all resources, fossil and otherwise, and the need to change our expectations, goals and lifestyles. In this effort, the role of deglobalisation/relocalisation may prove critical: thus, food and other necessities might be produced more on...

Biodegradation of Wasted Bioplastics in Natural and Industrial Environments: A Review

“…In addition, there are biodegradable plastics that are The possibility to produce bioplastics from waste is of extreme importance as replacing the production of conventional plastics with bio-based polymers would require about 0.02% of the total available Earth's arable land used for agricultural products [7]. This percentage is destined to increase by over 50% by 2050 for the estimated plastics' growth demand, leading to a serious question of whether land should be used for growing food crops, or as a tank for plastic, as had happened for first-generation biofuels that required significant land-based crops [8]. The majority of bioplastics is indeed still produced from agricultural crop-based feedstocks (carbohydrates and plant materials) [46] that both lead to increased water usage and to the reduction of food production [47].…”

“…Other common biodegradable polymers produced by plants, animals, micro-organisms, or synthetically are PGA, PCL, PBS, PBAT, and PHB [25,45]. Among them, PLA is considered the most promising, as lactic acid can be obtained from corn and other crops [8,25,65]. For instance, fermentable sugars obtained from chemical treatment of food waste can be used as substrate by microorganisms to produce plastics precursors [44].…”

“…It is estimated that the annual production of conventional (petrochemical) plastic can exceed the amount of 350 million tonnes [7]. However, their extensive utilization has led to serious environmental pollution issues mainly due to the high amount of disposable plastic items, which is about 50% of the total mass of plastics generated [8]. From 1950 to 2015, less than 10% of the overall amount of plastic waste that was produced was actually recycled, while the remaining part was landfilled or released to the environment [9].…”

“…Moreover, the ever-growing plastic waste that is accumulated into the landfills and in the marine environment [3,14,15] has a huge impact on the living organisms of these ecosystems [16], in particular sea mammals and turtles that confuse plastic waste for food often leading to their suffocation after swallowing it. Microplastics-plastic particles characterized by a diameter less than 5 mm derived from macroplastics' degradation [17]-have been identified not only in food, drinking water, soil, and the air but also in the least expected areas, such as deep sediments around Antarctica and the ice of the Arctic [8]. Furthermore, microplastics, accounting for about 13% of the plastic waste mass [18], and macroplastics may be mistaken for food by living organisms, which would be lethal as they would cause injuries [11,19,20] or lead to detrimental effects on human health as a consequence of being ingested [21].…”

“…The long-term existence of plastics in the environment [2,5,11,16,20,22] as well as their resistance to degradation led to the development of new materials, the biodegradable bioplastics [23,24]. These materials may be decomposed by the same abiotic mechanisms that allow the disintegration of conventional plastics, such as photodegradation, oxidation, and hydrolysis [25] as well as by microbial degradation [8]. According to recent estimates [7], global bioplastics generation capacity slightly exceeds 2.1 million tonnes, which is equivalent to 0.6% of the global plastic generation.…”