Plastic is not fantastic

Plastic is not nature

Plastic materials is any of a wide range of synthetic compounds that are malleable. Plastics often contain many chemical substances and are commonly derived from petrochemicals, but some are partially natural. It takes about 2 kg oil for every 1 kg plastic production, from a life-cycle perspective. The more advanced plastics requires more energy for production. Due to their relatively low cost, ease of manufacture, versatility and imperviousness to water plastics are used in an enormous and expanding range of products from food packaging to computers and cars. Motivated by the finiteness of oil and threat of climate change, bioplastics are being developed from cellulose and starch. Most plastics, however, are durable and degrade very slowly, some taking centuries. Plastic pollution pose as a major problem for the world's marine life and food web. 

Using the world’s oceans as a dump

Humans have little consideration for how much waste we continuously dump into the world's oceans and its effects on marine life. Plastic pollution is nowadays common throughout the marine environment. In a new study in PLOS, scientists from the US, France, Chile, Australia and New Zealand report for the first time an estimated number of 5 trillion pieces of plastic in total afloat at sea. With a collective weight of over 250 000 tonnes, it weighs more than the entire biomass of humans (Guardian, 2014). The volume of plastic pieces, largely derived from products such as food and drink packaging and clothing was calculated from data collected in 24 expeditions during 2007-2013 across five sub-tropical gyres.
Seal trapped in plastic pollution. Photo: Nels Israelson CC-BY-NC

Plastics and Marine Life

Large pieces of plastic can strangle animals such as seals, while smaller pieces are ingested by fish and then fed up the food chain, all the way to us humans. Chemicals contained within plastics and the pollutants they attract once they’re in the marine environment are toxic and can cause great harm to animals and humans. It’s hard to tell how much pollution is being ingested by marine life but plastics definitely contribute to increased toxins along the food web. While spread out around the globe, much of the plastic accumulates in five large ocean gyres, which are circular currents that churn up plastics in a set area. The gyres contribute to the problem because they shred the plastic before dispersing it. This micro-plastic continue to disperse and interact with entire ocean ecosystems (see figure 1 and 2).
Fig.1 Pieces of plastic debris by size, pieces per square km

Fig.2 Weight of plastic debris by size, grams per square km

Plastic: the last frontier of recycling

Researchers predict the volume of plastic pollution will increase due to rising production of throwaway plastic, with only 5% of the world’s plastic currently recycled. Policymakers need to understand the scale of the problem and take action accordingly. Some countries have taken measures to restrict plastic pollution. Germany has changed policy so that manufacturers are responsible for the waste they produce. By putting more responsibility on producers a larger shift towards recycling in possible. Recycling plastic can save energy and reduce carbon pollution but a major hindrance is how to sort plastics effectively since its made up out of so many different chemical compounds (polymers). 700 000 tonnes plastic is thrown away unsorted in the Nordic countries every year. Three new reports (2014) from the Nordic Council of Ministers describe methods for improving collection, sorting, and recycling of plastic waste in the Nordic countries. “Collection and recycling of plastic waste” presents the first steps towards improved nordic systems for collection and recycling. Every year 65 000 tonnes of plastic is burned at recycling stations.“Guideline for plastic sorting at recycling centres” looks at municipal recycling station practices for increasing collection of plastic materials of higher quality. Despite usable recycling techniques being available, less than 30% of plastic waste is recycled. “Plastic value chains - Case WEEE” identifies a substantial potential for increased recycling of plastics from electronic waste. This field is an excellent case where circular economy principles could be applied, the potential for improvements being large.


Out of the ashes into the fire

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