From enzymes that eat polyester clothing to policy effectiveness, the University of Portsmouth is at the forefront of research into ways to end the scourge of plastic pollution
This article was originally published on theguardian.com as part of the University of Portsmouth and Guardian Labs campaign.
How can society move from a linear throwaway plastics economy to a circular, more sustainable one?
As the detection of microplastics in human blood demonstrates, plastics have become intertwined in our everyday existence, and the challenge of combating this global problem is huge.
At the University of Portsmouth, the Revolution Plastics initiative has assembled researchers, businesses, campaigners and others to transform the way we make, use and dispose of plastic.
“We urgently need to tackle the plastic problem in a systemic way,” says Steve Fletcher, professor of ocean policy and economy, who leads the initiative.
Here are just some of the ways the university is leading in the search for solutions to the global plastics crisis.
Plastic-eating enzymes
Portsmouth scientists have been engineering PETase, an enzyme that digests PET (polyethylene terephthalate).
Since the discovery of plastic-eating bacteria at a rubbish dump in Japan in 2016, University of Portsmouth scientists have been engineering PETase, an enzyme that digests PET (polyethylene terephthalate), the material that most plastic bottles are made from.
Fletcher says that PETase breaks down complex polymer chains into their smaller building blocks, which can then be reconstructed. In its earlier iterations, PETase worked slowly, but the latest form digests PET more quickly, offering the potential for large-scale recycling.
Fletcher is clear, though, that recycling should be the last resort, because the priority is to reuse items and keep plastics in circulation for as long as possible rather than creating products that are discarded after a single use. But some goods, such as medical supplies, cannot be reused and so a form of low-energy clean recycling is needed.
One of the major challenges of recycling is the many different types of plastic in use, so Portsmouth’s scientists are in the early stages of addressing this issue. “Ideally, what we need is a mix of enzymes that can digest many types of plastic,” says Fletcher. “So here, researchers are developing enzyme cocktails that work on a whole variety, including polyester used in clothing.”
Scaling up this process to give waste plastic real financial value would transform recycling, he adds.
Recycling is not the university’s only focus. It is also investigating ways to reduce the impact of plastic on the environment, with researchers developing fishing gear and food packaging that are ultimately biodegradable. “Innovation and good design is undoubtedly part of the solution to the plastics challenge,” Fletcher says.
Global bans on plastics
“This is a once-in-a-generation opportunity. We need to be bold and take some big decisions around tackling what has become an urgent global crisis - Steve Fletcher.”
Around the world, many countries are initiating bans on a range of single-use plastic products but without, it appears, much coordination or understanding of their likely effectiveness.
In the UK, single-use plastic straws, stirrers and cotton buds are already on the banned list, while items such as single-use plates and cutlery are due to be added in October. France no longer permits single-use plastic bags or packaging for fresh fruit and veg, while India’s banned list includes plastic straws, cutlery and carrier bags.
“That all sounds great but national level policy is often sector-specific and isolated, so it does little to shift the global system that creates plastic pollution,” says Fletcher. “Only global action can have the reach, influence, and power to shift the dial when it comes to changing the plastics economy.”
To this end, the University of Portsmouth has launched the Global Plastics Policy Centre to analyse the effectiveness of plastic policies from around the world. It’s a “one-stop shop” of independent, evidence-based policy advice for governments and businesses who need to make informed decisions around plastic policies.
With a number of governmental, NGO and international partners, the Global Plastics Policy Centre is supporting negotiations for the development of a legally binding global treaty to end plastic pollution. The aim is to phase down the amount of new plastic entering the economy, which in turn will reduce pollution. Given that the manufacture of plastics from petrochemicals is a significant driver of the climate crisis, this policy could help the world towards net zero targets too.
Possible new approaches include a tax on virgin plastic, standardising plastic packaging production so that items are easier to reuse and recycle, banning all unnecessary single-use plastics and those that are hard to recycle, and a ban on all toxic additives. “There’s no justification for several categories of plastic even being produced in the first place,” says Fletcher. “What is needed is a broad range of policies that interact and support each other, and which consider climate, health, biodiversity loss and economy because they’re intrinsically connected. Currently, plastic policy tends to be rather fragmented. For policies to work, there needs to be a systemic change.”
Working with people for change
“So many people think plastic pollution is all about litter in the sea.” In fact most plastic pollution is on land.
The charity Tearfund, which works to reduce poverty, estimates that in developing countries 400,000 to 1 million people die each year from diseases related to mismanaged waste, particularly the toxic fumes emitted when plastic rubbish is burned. “Plastic pollution is an urgent health issue, particularly in the global south, where many lives are being put at risk ,” says Fletcher.
Fletcher’s team works with people living in Lamu, an archipelago off the Kenyan coast, to find solutions to plastic pollution on land as well as at sea. Lamu’s economy is dependent on more than 10,000 donkeys. Many graze in areas where plastic waste is littered and dumped, and ingest plastic, resulting in effects ranging from loss of body condition to death. The detrimental effects extend beyond animal welfare to those people whose livelihoods depend on these animals.
The university’s research into the impact of plastic pollution will help to inform potential future waste management strategies. “We’re looking to find solutions that work for everybody to reduce the amount of waste entering nature,” says Fletcher. “We’re bringing together donkey owners, local vets, business owners and residents to discuss ways to improve donkey welfare. We will work with a local theatre group to raise awareness of the issues among the wider community and motivate change.”
Revolution Plastics collaborated with Flipflopi, a Lamu-based initiative which is developing innovative community-led waste management solutions across east Africa, and has constructed a sailing dhow out of recycled plastic to promote its work.
Flipflopi recently established a heritage boat-building training centre to tackle plastic pollution in the Lamu archipelago, using recycled plastic instead of wood. Local people are paid for the plastic they collect, which is then recycled into canoes, fence posts, furniture and other items, helping the local economy and creating jobs. The University of Portsmouth contributed to developing and delivering the course curriculum.
“During the course, the students visit a slaughterhouse to see the kilos of plastic inside cows’ stomachs. They also learn about circular business models and build a canoe out of plastic,” says Fletcher, who says that projects such as this build people’s capacity to act differently and find healthier solutions. “We’re empowering local communities by co-designing solutions that work for them.”
