Worldwide production of plastics has more than tripled since 1990, reaching 331 million tonnes in 2014 and projected to more than triple again to well over one billion tonnes by 2050 (World Economic Forum, 2016). Yet the boon of convenient practicality that plastic products have arguably brought to modern life belies the monstrous economic and environmental problem that has arisen due to their almost-indestructibility.
The roots of the problem with nearly all plastics are two-fold: most take decades or even centuries to biodegrade, and yet most consumer plastic products are one-use only – think of plastic shopping bags, soft-drink bottles and other food packaging. It’s a linear economy: use something once then dispose of it. Relatively little is recycled; most ends up in landfill sites or, worse, the sea.
Just taking plastic bags as one example, between 500 billion and one trillion bags are made worldwide each year and fewer than 5% of these are recycled. Most are made of polyethylene, of which 80 million tonnes are produced worldwide annually and it can take up to a century for polyethylene to decompose.
Behind these figures is a major environmental challenge – processing the 86% of plastics that is not recycled and has ended up as waste, including in the oceans. In fact, a Texas-sized continent of plastics has formed in the Pacific Ocean – the largest of five similar ‘gyres’ circling in each of the world’s oceans. According to a report by the Ellen McArthur Foundation, some eight million tonnes of plastic ends up in the world’s oceans each year. Plastic microparticles drifting with the currents are absorbed by marine organisms that are eaten by fish and marine mammals and thus reach the top of the food chain, threatening both biodiversity and human health.
Reducing mankind’s apparent addiction to hydrocarbon-based plastic packaging – as well as reducing the massive waste piles that already exist – might appear insurmountable tasks. But increasing numbers of both large and start-up companies are investing in finding solutions to these problems – and not just for altruistic reasons: the potential cost of not doing so runs into billions of dollars a year.
The Ellen McArthur Foundation report cited above, which claims to offer ‘a blueprint to design a circular future for plastics’, notes: “[In] assessing global plastic packaging flows comprehensively for the first time, most plastic packaging is used only once; 95% of the value of plastic packaging material, worth USD 80-120 billion annually, is lost to the economy. Additionally, plastic packaging generates negative externalities, valued conservatively by the UN Environment Programme at USD 40 billion. Given projected growth in consumption, by 2050 oceans are expected to contain more plastics than fish (by weight), and the entire plastics industry will consume 20% of total oil production, and 15% of the annual carbon budget.”
The research and innovation in this field is both dynamic and varied. Among the large companies responding to the problem are two major drinks groups, Nestlé and Danone. According to a report in the Financial Times, they have teamed up to invest in research on producing bottles for products such as Perrier and Evian mineral water made from sawdust or farm crop residues.
But there are also many smaller-scale initiatives being reported from around the world. A Dutch teenager, Boyan Slat, determined to find a viable solution to ‘the impossible problem’ of removing plastic waste from the oceans, has managed to gather a crowd-funded, crowd-sourced group of scientists and engineers to work on the problem. The resulting organisation – named The Ocean Cleanup – claims that a full-scale deployment of its systems is estimated to remove half of ‘the Great Pacific Garbage Patch’ in five years. Its system of floating pipes, guided by solar-powered electronics, is designed to gather the waste to a concentrated point for easy removal.
In Spain, a researcher at the Institute of Biomedicine and Biotechnology of Cantabria found by chance that the caterpillar of the greater wax moth (Galleria mellonella), can eat polyethylene and digest it more quickly than other organisms can. It is as yet unclear whether this discovery may one day lead to large-scale plastic waste removal applications. And as the adult moth is a beehive parasite, it also raises the question of how to control the caterpillar populations so as not to put even further pressure on the world’s threatened bee populations.
Other ideas for reducing the amount of plastic waste from landfills around cities have already proven more successful. In India, a chemistry professor has developed a process to include plastic waste to replace 15% of more expensive bitumen in the mix used to lay roads. The technique requires no significant technical knowledge or changes to existing road-laying procedures. It has already been tested in India, where more than 5 000 km of ‘plastic’ roads have been laid.
And in the US, an architectural graduate has won awards for his idea of granulating waste plastic that would otherwise be dumped in landfills and instead including it in a cement mix. The concrete he created is as strong as traditional concrete made with completely mined aggregate. By reclaiming and integrating plastic in the concrete mix, he eliminated the need to recycle the plastic and spared both the financial and environmental cost of mining virgin aggregate.
BNP Paribas Asset Management's environmental experts pay close attention to how innovations of this kind can result in major breakthroughs in environmental protection and watching which companies will be able to benefit.
Written on 30 May 2017