Plastics in the world’s oceans, whether floating or resting at the bottom, is a problem that’s on the rise, and is said to have “reached crisis proportion.”
And while they may be assumed to be more eco-friendly, plastics labeled “biodegradable” still pose a threat to marine environments, a new United Nations study has found.
The report from the UN Environment Programme (UNEP), Biodegradable Plastics and Marine Litter. Misconceptions, Concerns and Impacts on Marine Environments (pdf), explains how these products still fail to tackle the growing problem.
The agency’s executive director, Achim Steiner, underscored the magnitude of the problem. “Recent estimates from UNEP have shown as much as 20 million tonnes of plastic end up in the world’s oceans each year. Once in the ocean, plastic does not go away, but breaks down into microplastic particles.”
The report notes that just what proportion of this plastic is biodegradable versus non-biodegradable has yet to be analyzed.
One of the problems, the report states, is that in order for some of the plastic debris to be completely broken down, conditions found in industrial compositing units that can achieve prolonged temperatures of above 50°C are needed. Yet those conditions “are rarely if ever met in the marine environment.”