Researchers used artificial intelligence to pinpoint four new policies they say could reduce the amount of "mismanaged" plastic waste -- more likely to leak into the environment -- by over 90 percent by 2050.

The University of California scientists hope their findings will inform negotiations to agree the world's first treaty on plastic pollution that began Monday in Busan.

The policies are: investment into waste-management infrastructure, limits on virgin plastic production, financial measures such as a packaging tax, and mandating that new products contain at least 40 percent recycled plastic.

They are "by no means a panacea" to the huge problem of plastic pollution, cautioned Neil Nathan of the University of California, Santa Barbara.

But when implemented together, the measures could reduce annual levels of mismanaged plastic waste to around 11 million metric tons by 2050, compared with 121 million under a business-as-usual projection.

"These are the four from our model that seemed to be the most impactful, or be the biggest bang for your buck, while also balancing what is most feasible," Nathan told AFP.

The researchers set out to simulate the effects of policies that could be included in the global treaty.

They created an interactive tool showing the predicted impact of measures like increased recycling or a reduction in single-use plastics on different regions.

"We decided to use artificial intelligence to be a bit more adaptive to... socioeconomic changes, changes in GDP, changes in population," said Nathan.

Plastic production is expected to triple by 2060, and over 20 million tonnes of plastic waste spills into the environment each year.

Nations gathered in South Korea are hoping to cap two years of negotiations on a treaty to end plastic pollution, but they remain deeply divided, including on whether to limit plastic production or certain chemicals.

Nathan said he hoped to see the treaty include "innovative financing mechanisms where we can create global funds" to improve waste management, especially in developing countries where the problem is most acute.

"That is 100 percent core to a successful treaty, and in terms of reducing the burden of this problem."