New battle lines drawn for plastics biodegradability

The recent Loughborough University report on oxodegradable plastics was supposed to draw a line under the long-running argument between the champions of different types of degradability.

Instead, it appears to have inflamed passions still further, and UK oxodegradable additive manufacturer Symphony Environmental has come out fighting.

The European Bioplastics industry association claimed the report, sponsored by the Department for Environment, Food & Rural Affairs, had "rattled" the oxodegradables sector. Instead, Symphony said it was "irritated by its inaccuracy". It also called the report "incomplete" and "misleading".

Technical director at Symphony Michael Stephens commented: "It was flawed as a review, very arms-length, with no real scientific aspect to it."

The tussle could intensify still further if, as Stephens has predicted, a British Standard for oxodegradables is published by the end of the year. This could potentially create a European standard competing with the EN 13432 biodegradability standard.

Oxodegradables combine traditional oil-based polymers with additives that cause the films to fragment under given conditions. But Symphony and others have been working to demonstrate that they genuinely biodegrade. They have also been struggling with the testing and standardisation of films with differing degradability specifications and 'life expectancies'. Unlike bio-based biodegradables, these films can take months or even years to break down completely.

Meanwhile, the bioplastics industry has moved away from debating whether or not these materials biodegrade. Chair of European Bioplastics Andy Sweetman argued: "You have to ask how your technology contributes to the cause of sustainability. For biodegradable polymers, it's easy to come up with proof of renewability, compostability and biodegradability."

The same is not true of oxodegradables, he claimed, since degradation times are excessive. "They may well be biodegradable, but whether they end up in industrial composting or anaerobic digestion there's going to be a set timetable so what's the point?"

Stephens at Symphony believes this argument is irrelevant. "No one is going to collect these materials and point them in the direction of biodigestion," he said. "It's a dreamworld scenario."