In theory, oxo-degradable plastics sound fantastic. Developed in the 1970s, they are made by mixing in an additive during the manufacturing process that weakens the carbon chains, making it easier for the plastic to break down when it’s exposed to UV light, oxygen and heat. In accelerating the breakdown of plastics into smaller pieces, they biodegrade more quickly, so the claim goes. The reality, however, is somewhat different from the concept.
"It would be great if it actually worked," says David Newman, president of World Biogas Association and Managing Director of the Bio-based and Biodegradable Industries Association (BBIA). "The problem is no one's actually found the formula yet to make it work." An April 2023 paper by UCL researchers concluded that “there is little data to substantiate the claim that PAC plastics [pro-oxidant additive containing plastics, another term for oxo-degradable plastics] fully biodegrade after the abiotic degradation stage”. In other words, there is very little evidence to support the much hyped claims. It’s a category of plastics that makes a lot of promises but in fact could be doing more harm than good.