Comment: Closing the loop on plastic waste
In 2017, US researchers estimated that 6.3bn tonnes of plastic waste has been generated globally since the 1950s, of which almost 80% has accumulated in landfills or the natural environment. Significant volumes of this waste enter marine environments, much of it fragmented into microplastic particles that are difficult to retrieve and can be ingested by fish, birds and other marine life. Combined with the potential for larger pieces of plastic waste to entangle animals, the risks for marine ecosystems are clear.
What is less well understood are the potential health implications for humans of plastics entering the food chain or contaminating water stocks – a concern which is being fuelled by emerging evidence on the extent of plastics pollution from microbeads in cosmetics and fibres released from synthetic textiles during washing.
Despite these concerns, the fact remains that plastic is a durable, cheap and versatile material that performs many useful functions. Plastic packaging helps to preserve food and reduce wastage, plastic components are a lighter and more fuel-efficient alternative to metal in vehicle components, and surgical gloves and single-use syringes are vital in preventing infection in healthcare environments. The economic importance of plastics is also difficult to understate, with the plastics industry in the EU alone employing over 1.4 million people and contributing more than €350bn to the European economy.
It is not plastics themselves, but rather our relationship with them in a linear economic model of production, consumption and waste that leads to problems. How then do manufacturers, producers and consumers work together to cut unnecessary use and close the loop on plastic waste?
The circular economy
Strategies aimed at tackling global plastic pollution are taking their lead from the circular economy by considering how existing resources can be recovered, reformulated and continuously recycled back into supply chains. Currently, recycling volumes are too low and methods too imperfect to adequately repurpose all types of plastic, but a growing number of initiatives are focusing on improvements in product and packaging design, in waste collection and in systems for processing recyclate. Aside from the environmental benefits, this makes economic sense as it preserves the value of polymers for reuse.
There are numerous initiatives underway which seek to redefine our relationship with plastics. Converting plastic bottles into sports shoes or car interiors, for example, indicates a growing trend in more unconventional material repurposing. Manufacturers are looking to reduce the environmental impact of polymer production, cutting costs associated with energy and resource use. Growing awareness of the environmental impact of single-use plastic waste is prompting food producers and other suppliers of consumer goods to reduce levels of plastic in packaging and investigate biodegradable or fibre-based alternatives. And consumer habits are changing through the imposition of taxes on plastic bags and their proposed extension to other single-use items such as takeaway coffee cups.
Producers also need to increase the scope of recovery systems in their supply chains to help prevent unnecessary waste. Technology such as reverse vending machines (which collect, identify and sort recyclable containers deposited by consumers) help to increase waste collection volumes while reducing problems caused by mixed materials or contamination in recyclate. More broadly, the concept of “reverse logistics” (whereby waste is diverted for use as an input in another process) is delivering benefits in both developed and developing economies, limiting environmental damage and supporting material recovery and reuse.
Successful innovation, more robust public policy and enhanced business models are likely to galvanize similar actions across plastics industries worldwide. With the environmental consequences of waste very much in the public eye at present, the financial and reputational risks of failing to explore sustainable alternatives are particularly high.