Most home compostable plastics don't break down, study finds

The majority of plastics marketed as “home compostable” do not fully disintegrate and end up settling in soil, new research has found.

The UK-based study, called The Big Compost Experiment, found that 60 per cent of home compostable plastics - used for items such as food packaging, bags and cutlery - do not break up within six months.

An author the study, Danielle Purkiss, said: “Compostable packaging does not break down effectively in the range of UK home composting conditions, creating plastic pollution.”

She added: “Even packaging that has been certified as home compostable is not breaking down effectively.”

The study found only 10 per cent of people can effectively compost plastics at home. for everyone else, landfills are the best place to dispose of compostable plastics.

The Big Compost Experiment, which analysed data from 9,700 people, also showed that participants were confused about the labelling and identification of these plastics.

Out of a random sample of 50 plastic packaging images, 46 per cent showed no identifiable home composting certification or standards labelling and 14 per cent showed an industrial composting certification.

Professor Mark Miodownik, who also helped write the study, published in the journal Frontiers in Sustainability, told The Guardian: “The bottom line is that home compostable plastics don’t work. Let’s just stop. Let’s not pretend to ourselves that it’s going to be some sort of panacea, and you can sell people stuff without really having infrastructure to deal with the waste and hope that it’s all going to go away.”

Another study by an international organisation called The Organisation for Economic Cooperation and Development (OECD), reported that plastic consumption has increased worldwide by over four folds in the past 30 years and only nine per cent of plastic waste is recycled.

The OECD work with 38 countries and stated that “plastic pollution is growing relentlessly.”

Compostable plastics are becoming more common as the demand for sustainability grows. The main use of compostable plastics includes food packaging, bags; cups and plates, cutlery, and bio-waste bags. But there are problems with these types of plastics as they are largely unregulated and claims about their environmental benefits are often exaggerated.

In response to this pollution crisis, several countries have set targets to cut down and eliminate all single-use plastics and to make plastic packaging 100 per cent recyclable, reusable, or compostable by 2025.