The failure of recent global talks in Busan, South Korea, to produce a landmark treaty to combat plastic pollution, has underscored the complexities and challenges of addressing one of the planet’s most pressing environmental and climate issues.

More than 100 countries want the treaty to limit production as well as tackle cleanup and recycling, which is essential to address chemicals of concern.

Negotiators at a U.N. plastic pollution summit in Busan, South Korea are pushing for a legally binding treaty that would set global plastic production reduction targets.