̽��ֱ�� of Cambridge - plastic

Scientists warn of ‘invisible threat’ of microplastics as global treaty nears completion

sc604 — Tue, 26 Nov 2024 10:50:47 +0000

Even if global production and pollution of new plastic is drastically reduced, scientists, writing in the journal Nature Communications, say that legacy plastics, the billions of tonnes of waste already in the environment, will continue to break down into tiny particles called microplastics for decades or centuries.

These fragments contaminate oceans, land, and the air we breathe, posing risks to marine life, food production and human health.

̽��ֱ��researchers – from the ̽��ֱ�� of Cambridge, GNS Science in New Zealand and ̽��ֱ��Ocean Cleanup in ̽��ֱ��Netherlands – say the problem lies in a gap between ambition and action, called the fragmentation gap.

At a meeting this week in Busan, South Korea, the Intergovernmental Negotiating Committee on Plastic Pollution is meeting to finalise the Global Plastics Treaty, the first legally binding treaty to tackle plastic pollution.

While the treaty’s initial discussions highlight prevention of plastic pollution, the researchers say it largely overlooks the need to remove existing waste. This omission means microplastics will continue to accumulate, even if plastic pollution slows.

“ ̽��ֱ��treaty is aiming to eliminate plastic pollution by 2040, but this goal is unlikely without stronger action,” said co-author Zhenna Azimrayat-Andrews, a PhD student at Cambridge’s Department of Earth Sciences. “Even with a sharp reduction in plastic entering the ocean, existing debris will split into smaller pieces and persist for centuries.”

These microplastics have already infiltrated marine ecosystems and are harming marine ecosystems, degrading commercial seafood quality, and disrupting critical ocean processes.

̽��ֱ��researchers argue that plastic clean-up efforts must be prioritised alongside reduction targets. Strategies to remove plastics from terrestrial and marine environments, such as those targeting pollution in beaches and rivers, could help prevent microplastics from forming. In fact, a 3% annual removal of legacy plastic, combined with aggressive reduction measures, could significantly curb future contamination, they say.

Without action to address legacy plastic, the treaty risks leaving behind a long-lasting problem for marine life and future generations. Experts are calling for clean-up efforts to become an equal pillar of the treaty, alongside prevention and recycling.

As world leaders gather to negotiate the treaty this week, the spotlight is on their ability to craft a comprehensive plan that doesn't just slow pollution but also begins to reverse the damage that has already been done.

Reference:
Karin Kvale, Zhenna Azimrayat Andrews & Matthias Egger. ‘Mind the fragmentation gap.’ Nature Communications (2024). DOI: 10.1038/s41467-024-53962-3

As the UN meets this week to finalise the Global Plastics Treaty, researchers warn that the agreement could fail to address one of the biggest threats to marine environments—microplastics.

Alistair Berg via Getty Images

Researcher holding small pieces of micro plastic pollution washed up on a beach

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Plastic Fantastic Cambridge

plc32 — Wed, 13 Mar 2024 13:48:55 +0000

Cambridge ̽��ֱ�� Association Football Club (CUAFC) will wear a design that copies the match kit from their 1905 Varsity fixture with Oxford for this year's 150th Anniversary Varsity match. But the shirts, socks and shorts for the 39th Women’s Varsity Match and the 139th Men’s Varsity Match in Cambridge on Friday 15th March are a modern marvel of recycling innovation.

A habitable planet for healthy humans

plc32 — Wed, 13 Dec 2023 17:28:42 +0000

Cambridge Zero symposium gathers researchers to examine the connections between planetary and public health.

World’s most threatened seabirds visit remote plastic pollution hotspots

jg533 — Tue, 04 Jul 2023 15:00:00 +0000

̽��ֱ��extensive study assessed the movements of 7,137 individual birds from 77 species of petrel, a group of wide-ranging migratory seabirds including the Northern Fulmar and European Storm-petrel, and the Critically Endangered Newell’s Shearwater.

This is the first time that tracking data for so many seabird species has been combined and overlaid onto global maps of plastic distribution in the oceans.

̽��ֱ��results show that plastic pollution threatens marine life on a scale that transcends national boundaries: a quarter of all plastic exposure risk occurs in the high seas. This is largely linked to gyres - large systems of rotating ocean currents - where vast accumulations of plastics form, fed by waste entering the sea from boats, and from many different countries.

Seabirds often mistake small plastic fragments for food, or ingest plastic that has already been eaten by their prey. This can lead to injury, poisoning and starvation, and petrels are particularly vulnerable because they can’t easily regurgitate the plastic. In the breeding season they often inadvertently feed plastic to their chicks.

Plastics can also contain toxic chemicals that can be harmful to seabirds.

Petrels are an understudied but vulnerable group of marine species, which play a key role in oceanic food webs. ̽��ֱ��breadth of their distribution across the whole ocean makes them important ‘sentinel species’ when assessing the risks of plastic pollution in the marine environment.

“Ocean currents cause big swirling collections of plastic rubbish to accumulate far from land, way out of sight and beyond the jurisdiction of any one country. We found that many species of petrel spend considerable amounts of time feeding around these mid-ocean gyres, which puts them at high risk of ingesting plastic debris,” said Lizzie Pearmain, a PhD student at the ̽��ֱ�� of Cambridge’s Department of Zoology and the British Antarctic Survey, and joint corresponding author of the study.

She added: “When petrels eat plastic, it can get stuck in their stomachs and be fed to their chicks. This leaves less space for food, and can cause internal injuries or release toxins.”

Petrels and other species are already threatened with extinction due to climate change, bycatch, competition with fisheries, and invasive species such as mice and rats on their breeding colonies. ̽��ֱ��researchers say exposure to plastics may reduce the birds’ resilience to these other threats.

̽��ֱ��north-east Pacific, South Atlantic, and the south-west Indian oceans have mid-ocean gyres full of plastic waste, where many species of threatened seabird forage.

“Even species with low exposure risk have been found to eat plastic. This shows that plastic levels in the ocean are a problem for seabirds worldwide, even outside of these high exposure areas,” said Dr Bethany Clark, Seabird Science Officer at BirdLife International and joint corresponding author of the study.

She added: “Many petrel species risk exposure to plastic in the waters of several countries and the high seas during their migrations. Due to ocean currents, this plastic debris often ends up far away from its original source. This highlights the need for international cooperation to tackle plastic pollution in the world’s oceans.”

̽��ֱ��study also found that the Mediterranean Sea and the Black Sea together account for over half of petrels’ global plastic exposure risk. However, only four species of petrel forage in these enclosed, busy areas.

̽��ֱ��study was led by a partnership between the ̽��ֱ�� of Cambridge, BirdLife International and the British Antarctic Survey, in collaboration with Fauna & Flora International, the 5 Gyres Institute, and over 200 seabird researchers in 27 countries.

It was published on 4 July in the journal Nature Communications.

To get their results, the researchers overlaid global location data, taken from tracking devices attached to the birds, onto pre-existing maps of marine plastic distribution. This allowed them to identify the areas on the birds’ migration and foraging journeys where they are most likely to encounter plastics.

Species were given an ‘exposure risk score’ to indicate their risk of encountering plastic during their time at sea. A number of already threatened species scored highly, including the Critically Endangered Balearic Shearwater, which breeds in the Mediterranean, and Newell’s Shearwater, endemic to Hawaii.

Another Endangered species, the Hawaiian Petrel also scored high for plastic exposure risk, as did three species classified by the IUCN as Vulnerable: the Yelkouan Shearwater, which breeds in the Mediterranean; Cook’s Petrel, which breeds in New Zealand, and the Spectacled Petrel, which only breeds on an extinct volcano called Inaccessible Island, part of the Tristan da Cunha archipelago, a UK Overseas Territory.

“While the population-level effects of plastic exposure are not yet known for most species, many petrels and other marine species are already in a precarious situation. Continued exposure to potentially dangerous plastics adds to the pressures,” said Professor Andrea Manica at the ̽��ֱ�� of Cambridge’s Department of Zoology, a co-author of the study.

He added: “This study is a big leap forward in understanding the situation, and our results will feed into conservation work to try and address the threats to birds at sea.”

̽��ֱ��research was funded by the Cambridge Conservation Initiative’s Collaborative Fund for Conservation, sponsored by the Prince Albert II of Monaco Foundation, and the Natural Environment Research Council.

Reference

Clark, B.L. et al.: ‘Global assessment of marine plastic exposure risk for oceanic birds.’ Nature Communications, July 2023. DOI: 10.1038/s41467-023-38900-z

Analysis of global tracking data for 77 species of petrel has revealed that a quarter of all plastics potentially encountered in their search for food are in remote international waters – requiring international collaboration to address.

Ocean currents cause big swirling collections of plastic rubbish to accumulate far from land

Lizzie Pearmain

Beth Clark

Northern Fulmar bird in flight

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Licence type:

Attribution

Solar-powered system converts plastic and greenhouse gases into sustainable fuels

sc604 — Mon, 09 Jan 2023 16:00:00 +0000

̽��ֱ��researchers, from the ̽��ֱ�� of Cambridge, developed the system, which can convert two waste streams into two chemical products at the same time – the first time this has been achieved in a solar-powered reactor.

̽��ֱ��reactor converts carbon dioxide (CO2) and plastics into different products that are useful in a range of industries. In tests, CO2 was converted into syngas, a key building block for sustainable liquid fuels, and plastic bottles were converted into glycolic acid, which is widely used in the cosmetics industry. ̽��ֱ��system can easily be tuned to produce different products by changing the type of catalyst used in the reactor.

Converting plastics and greenhouse gases – two of the biggest threats facing the natural world – into useful and valuable products using solar energy is an important step in the transition to a more sustainable, circular economy. ̽��ֱ��results are reported in the journal Nature Synthesis.

“Converting waste into something useful using solar energy is a major goal of our research,” said Professor Erwin Reisner from the Yusuf Hamied Department of Chemistry, the paper’s senior author. “Plastic pollution is a huge problem worldwide, and often, many of the plastics we throw into recycling bins are incinerated or end up in landfill.”

Reisner also leads the Cambridge Circular Plastics Centre (CirPlas), which aims to eliminate plastic waste by combining blue-sky thinking with practical measures.

Other solar-powered ‘recycling’ technologies hold promise for addressing plastic pollution and for reducing the amount of greenhouse gases in the atmosphere, but to date, they have not been combined in a single process.

“A solar-driven technology that could help to address plastic pollution and greenhouse gases at the same time could be a game-changer in the development of a circular economy,” said Subhajit Bhattacharjee, the paper’s co-first author.

“We also need something that’s tuneable, so that you can easily make changes depending on the final product you want,” said co-first author Dr Motiar Rahaman.

̽��ֱ��researchers developed an integrated reactor with two separate compartments: one for plastic, and one for greenhouse gases. ̽��ֱ��reactor uses a light absorber based on perovskite – a promising alternative to silicon for next-generation solar cells.

̽��ֱ��team designed different catalysts, which were integrated into the light absorber. By changing the catalyst, the researchers could then change the end product. Tests of the reactor under normal temperature and pressure conditions showed that the reactor could efficiently convert PET plastic bottles and CO2 into different carbon-based fuels such as CO, syngas or formate, in addition to glycolic acid. ̽��ֱ��Cambridge-developed reactor produced these products at a rate that is also much higher than conventional photocatalytic CO2 reduction processes.

“Generally, CO2 conversion requires a lot of energy, but with our system, basically you just shine a light at it, and it starts converting harmful products into something useful and sustainable,” said Rahaman. “Prior to this system, we didn’t have anything that could make high-value products selectively and efficiently.”

“What’s so special about this system is the versatility and tuneability – we’re making fairly simple carbon-based molecules right now, but in future, we could be able to tune the system to make far more complex products, just by changing the catalyst,” said Bhattacharjee.

Reisner recently received new funding from the European Research Council to help the development of their solar-powered reactor. Over the next five years, they hope to further develop the reactor to produce more complex molecules. ̽��ֱ��researchers say that similar techniques could someday be used to develop an entirely solar-powered recycling plant.

“Developing a circular economy, where we make useful things from waste instead of throwing it into landfill, is vital if we’re going to meaningfully address the climate crisis and protect the natural world,” said Reisner. “And powering these solutions using the Sun means that we’re doing it cleanly and sustainably.”

̽��ֱ��research was supported in part by the European Union, the European Research Council, the Cambridge Trust, Hermann and Marianne Straniak Stiftung, and the Engineering and Physical Sciences Research Council (EPSRC), part of UK Research and Innovation (UKRI). Erwin Reisner is a Fellow of St John’s College, Cambridge.

Reference:
Subhajit Bhattacharjee, Motiar Rahaman et al. ‘Photoelectrochemical CO2-to-fuel conversion with simultaneous plastic reforming.’ Nature Synthesis (2023). DOI: 10.1038/s44160-022-00196-0

For more information on energy-related research in Cambridge, please visit Energy IRC, which brings together Cambridge’s research knowledge and expertise, in collaboration with global partners, to create solutions for a sustainable and resilient energy landscape for generations to come.

Researchers have developed a system that can transform plastic waste and greenhouse gases into sustainable fuels and other valuable products – using just the energy from the Sun.

A solar-driven technology that could help to address plastic pollution and greenhouse gases at the same time could be a game-changer in the development of a circular economy

Subhajit Bhattacharjee

Reisner Lab

Solar-powered reactor for converting plastic and greenhouse gases into sustainable fuels

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. Images, including our videos, are Copyright © ̽��ֱ�� of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – as here, on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Sustainable, biodegradable glitter – from your fruit bowl

sc604 — Thu, 11 Nov 2021 15:23:09 +0000

Cambridge researchers have developed a sustainable, plastic-free glitter for use in the cosmetics industry – and it’s made from the cellulose found in plants, fruits, vegetables and wood pulp.

‘Vegan spider silk’ provides sustainable alternative to single-use plastics

sc604 — Thu, 10 Jun 2021 09:00:00 +0000

̽��ֱ��researchers, from the ̽��ֱ�� of Cambridge, created a polymer film by mimicking the properties of spider silk, one of the strongest materials in nature. ̽��ֱ��new material is as strong as many common plastics in use today and could replace plastic in many common household products.

̽��ֱ��material was created using a new approach for assembling plant proteins into materials that mimic silk on a molecular level. ̽��ֱ��energy-efficient method, which uses sustainable ingredients, results in a plastic-like free-standing film, which can be made at industrial scale. Non-fading ‘structural’ colour can be added to the polymer, and it can also be used to make water-resistant coatings.

̽��ֱ��material is home compostable, whereas other types of bioplastics require industrial composting facilities to degrade. In addition, the Cambridge-developed material requires no chemical modifications to its natural building blocks, so that it can safely degrade in most natural environments.

̽��ֱ��new product will be commercialised by Xampla, a ̽��ֱ�� of Cambridge spin-out company developing replacements for single-use plastic and microplastics. ̽��ֱ��company will introduce a range of single-use sachets and capsules later this year, which can replace the plastic used in everyday products like dishwasher tablets and laundry detergent capsules. ̽��ֱ��results are reported in the journal Nature Communications.

For many years, Professor Tuomas Knowles in Cambridge’s Yusuf Hamied Department of Chemistry has been researching the behaviour of proteins. Much of his research has been focused on what happens when proteins misfold or ‘misbehave’, and how this relates to health and human disease, primarily Alzheimer’s disease.

“We normally investigate how functional protein interactions allow us to stay healthy and how irregular interactions are implicated in Alzheimer’s disease,” said Knowles, who led the current research. “It was a surprise to find our research could also address a big problem in sustainability: that of plastic pollution.”

As part of their protein research, Knowles and his group became interested in why materials like spider silk are so strong when they have such weak molecular bonds. “We found that one of the key features that gives spider silk its strength is the hydrogen bonds are arranged regularly in space and at a very high density,” said Knowles.

Co-author Dr Marc Rodriguez Garcia, a postdoctoral researcher in Knowles’ group who is now Head of R&D at Xampla, began looking at how to replicate this regular self-assembly in other proteins. Proteins have a propensity for molecular self-organisation and self-assembly, and plant proteins, in particular, are abundant and can be sourced sustainably as by-products of the food industry.

“Very little is known about the self-assembly of plant proteins, and it’s exciting to know that by filling this knowledge gap we can find alternatives to single-use plastics,” said PhD candidate Ayaka Kamada, the paper’s first author.

̽��ֱ��researchers successfully replicated the structures found on spider silk by using soy protein isolate, a protein with a completely different composition. “Because all proteins are made of polypeptide chains, under the right conditions we can cause plant proteins to self-assemble just like spider silk,” said Knowles, who is also a Fellow of St John's College. “In a spider, the silk protein is dissolved in an aqueous solution, which then assembles into an immensely strong fibre through a spinning process which requires very little energy.”

“Other researchers have been working directly with silk materials as a plastic replacement, but they’re still an animal product,” said Rodriguez Garcia. “In a way, we’ve come up with ‘vegan spider silk’ – we’ve created the same material without the spider.”

Any replacement for plastic requires another polymer – the two in nature that exist in abundance are polysaccharides and polypeptides. Cellulose and nanocellulose are polysaccharides and have been used for a range of applications, but often require some form of cross-linking to form strong materials. Proteins self-assemble and can form strong materials like silk without any chemical modifications, but they are much harder to work with.

̽��ֱ��researchers used soy protein isolate (SPI) as their test plant protein, since it is readily available as a by-product of soybean oil production. Plant proteins such as SPI are poorly soluble in water, making it hard to control their self-assembly into ordered structures.

̽��ֱ��new technique uses an environmentally friendly mixture of acetic acid and water, combined with ultrasonication and high temperatures, to improve the solubility of the SPI. This method produces protein structures with enhanced inter-molecular interactions guided by the hydrogen bond formation. In a second step, the solvent is removed, which results in a water-insoluble film.

̽��ֱ��material has a performance equivalent to high-performance engineering plastics such as low-density polyethylene. Its strength lies in the regular arrangement of the polypeptide chains, meaning there is no need for chemical cross-linking, which is frequently used to improve the performance and resistance of biopolymer films. ̽��ֱ��most commonly used cross-linking agents are non-sustainable and can even be toxic, whereas no toxic elements are required for the Cambridge-developed technique.

“This is the culmination of something we’ve been working on for over ten years, which is understanding how nature generates materials from proteins,” said Knowles. “We didn’t set out to solve a sustainability challenge -- we were motivated by curiosity as to how to create strong materials from weak interactions.”

“ ̽��ֱ��key breakthrough here is being able to control self-assembly, so we can now create high-performance materials,” said Rodriguez Garcia. “It’s exciting to be part of this journey. There is a huge, huge issue of plastic pollution in the world, and we are in the fortunate position to be able to do something about it.”

Xampla's technology has been patented by Cambridge Enterprise, the ̽��ֱ��'s commercialisation arm. Cambridge Enterprise and Amadeus Capital Partners co-led a £2 million seed funding round for Xampla, joined by Sky Ocean Ventures and the ̽��ֱ�� of Cambridge Enterprise Fund VI, which is managed by Parkwalk.

Reference:
A. Kamada et al. ‘Self-assembly of plant proteins into high-performance multifunctional nanostructured films.’ Nature Communications (2021). DOI: 10.1038/s41467-021-23813-6

Researchers have created a plant-based, sustainable, scalable material that could replace single-use plastics in many consumer products.

It was a surprise to find our research could also address a big problem in sustainability: that of plastic pollution

Tuomas Knowles

Xampla

Packaging incorporating Xampla's plant-based plastic

Yes

Plastic: the new fantastic?

lw355 — Fri, 05 Jun 2020 09:30:20 +0000

Plastic has become a malevolent symbol of our wasteful society. It’s also cheap, durable, flexible, waterproof, versatile, lightweight, protective and hygienic.

During the coronavirus pandemic, plastic visors, goggles, gloves and aprons have been fundamental for protecting healthcare workers from the virus. But what about the effects on the environment of throwing away huge numbers of single-use medical protection equipment? How are we to balance our need for plastic with protecting the environment?

Released on 5 June 2020, World Environment Day, this new film considers how society might ‘reset the clock’ when it comes to living better with a vital material. We hear how Cambridge ̽��ֱ��'s Cambridge Creative Circular Plastics Centre (CirPlas) aims to eliminate plastic waste by combining blue-sky thinking with practical measures – from turning waste plastic into hydrogen fuel, to manufacturing more sustainable materials, to driving innovations in plastic recycling in a circular economy.

“Plastic is an example of how we must find ways to use resources without irreversibly changing the planet for future generations,” adds Professor Erwin Reisner, who leads CirPlas, which is funded by UK Research and Innovation.

Explore more:

Find further information on CirPlas

Plastic: the new fantastic?

Taylor Uekert studies the transformation of plastic waste into hydrogen fuel

Yes