The Pew Charitable Trusts and SYSTEMIQ, with academics from Oxford, Leeds and elsewhere, built a global model of plastic flows to test which combination of interventions could end ocean plastic pollution.
They found that under business as usual, plastic entering the ocean rises from 11 million tonnes in 2016 to 29 million tonnes in 2040. Applying every feasible intervention at once, from reduction and reuse to better collection and recycling, cuts 2040 pollution by 78% compared with business as usual, or 40% below 2016 levels.
The study is the basis for the widely used '80% reduction is possible with existing technology' claim, and it shows that no single solution, including recycling, is enough on its own.
Its 2016 baseline of 11 million tonnes is one of several ocean-inflow estimates and should not be mixed with the Jambeck 2010 figure of 8 million tonnes or the Borrelle 2016 figure of 19–23 million tonnes, which use different scopes.