A global study has found that without immediate and sustained action, the annual flow of plastic into the ocean could nearly triple by 2040.

A rethink of the whole value chain of the functions provided by plastic is essential, and that no single policy or technical solution will suffice…Crucially, the increased use of plastic due to COVID-19 will heighten the urgency to develop interventions at all stages of the value chain. Dr Arturo Castillo Castillo Centre for Environmental Policy

Unless immediate and sustained action is taken globally, more than 1.3 billion tonnes of plastic will be dumped on land and in the oceans between 2016 and 2040, says a team of global experts who have analysed scenarios of interventions to tackle plastic pollution.

The analysis, led by The Pew Charitable Trusts and SYSTEMIQ and co-authored by a global team including Dr Arturo Castillo Castillo at Imperial College London, identifies solutions that could cut this volume by more than 80 per cent using a multi-pronged approach of currently available technologies.

These approaches include reducing growth in plastic production and consumption, substituting some plastics with alternatives such as paper, compostable materials and refillable packaging, designing recyclable products and packaging, expanding waste collection rates in middle- and low-income countries, increasing recycling, and reducing plastic waste exports.

Dr Castillo of Imperial’s Centre for Environmental Policy, who contributed expertise toward the ‘Reduce and Substitute’ analysis of interventions and their role in reducing infrastructure needs and preventing impacts said: “The time is now. The general public wants to see a response and we have the interventions at our fingertips to significantly reduce plastic leakage.”

The findings are published in Science.

Findings

We cannot reduce, recycle or dispose our way out of plastic pollution. None of the single-intervention strategies on their own can reduce annual leakage of plastic into the ocean below 2016 levels by 2040. Dr Arturo Castillo Castillo Centre for Environmental Policy

The research found that if no action is taken to address the projected growth in plastic production and consumption, the amount of plastic entering the ocean each year would grow from 11 million metric tonnes to 29 million metric tonnes over the next 20 years. This is equivalent to nearly 50 kilograms of plastic for each metre of coastline worldwide.

Because plastic remains in the ocean for hundreds of years and may never degrade, the cumulative amount of plastic in the ocean by 2040 could reach 600 million tonnes—equivalent in weight to more than 3 million blue whales.

Although progress has been made in addressing the global plastic challenge, the report found that current commitments by government and industry, even if they are successfully delivered, will reduce the amount of ocean plastic by only 7 per cent by 2040.

To ascertain the impact of solutions, the global team of experts used a new economic model that quantifies the potential amount of plastic in world oceans by 2040 under six scenarios. These scenarios range from no change to current approaches and projections (Business as Usual), to a total overhaul of the world’s plastics system (‘System Change’) - including its production, consumption, collection, recycling and disposal.

The work quantified the associated cost, climate, and employment implications of each scenario.

False dichotomy

To date, much of the debate has focused on either “upstream” interventions, such as plastic reduction and substitution, or “downstream” interventions, such as recycling and disposal.

Dr Castillo said: “Our study shows that this is a false dichotomy and clarifies that we cannot reduce, recycle or dispose our way out of plastic pollution. None of the single-intervention strategies on their own can reduce annual leakage of plastic into the ocean below 2016 levels by 2040.”

For example, an ambitious recycling strategy with scale-up of collection, sorting, and recycling infrastructure, coupled with design for recycling, reduces 2040 leakage by 38 per cent relative to the ‘business as usual’ scenario, which is 65 per cent above 2016 levels.

The scenarios

There’s no single solution to ocean plastic pollution, but through rapid and concerted action we can break the plastic wave. Tom Dillon The Pew Charitable Trusts

As well as the ‘business as usual’ scenario, the team studied scenarios including ‘Collect and Dispose’, ‘Recycling’, ‘Reduce and Substitute’, and an integrated ‘System Change’ scenario that used the entire suite of interventions. Under the ‘Reduce and Substitute’ scenario, annual combined terrestrial and aquatic plastic pollution in 2040 decreased 59 per cent relative to 'Business as Usual', while annual plastic production decreased by 47 per cent.

Dr Castillo argues that “a rethink of the whole value chain of the functions provided by plastic is essential, and that no single policy or technical solution will suffice.” He added that “crucially, the increased use of plastic due to COVID-19 will heighten the urgency to develop interventions at all stages of the value chain.”

The research also found that delaying interventions by five years could result in an additional 80 million metric tons of plastic going into the ocean by 2040. All elements of the ‘System Change’ scenario exist today or are under development and near adoption.

Tom Dillon, Pew’s Vice President for Environment, said: “There’s no single solution to ocean plastic pollution, but through rapid and concerted action we can break the plastic wave. As this work shows, we can invest in a future of reduced waste, better health outcomes, greater job creation, and a cleaner and more resilient environment for both people and nature.”

The researchers say this presents a unique opportunity for providers of new and existing materials and industries that use circular business models and reuse and refill systems, which are designed to keep products and materials in use for as long as possible.

The findings from the scientific analysis were released in a report, “Breaking the Plastic Wave: A Comprehensive Assessment of Pathways Towards Stopping Ocean Plastic Pollution.” The release coincides with the July 23 publication of the technical underpinnings of the report in an article in the journal Science, “Evaluating Scenarios Toward Zero Plastic Pollution.”

This news story was partly adapted from a press release by The Pew Charitable Trusts and SYSTEMIQ.

Dr Castillo is leader of the Ocean Plastic Solutions Network at Imperial (@OceanPlastic_IC), which co-produced the Briefing Paper with Imperial’s Institute of Molecular Science and Engineering

“Enabling a greener plastic future through molecular science”