Earlier this week, the University of Plymouth published research that questioned how good for the environment compostable, biodegradable or oxo-degradable bags are for the environment. It caused some confusion, with some members of the public not understanding the difference between the three, writes Daphna Nissenbaum, CEO of compostable bag company TIPA.
Since publication, the University of Plymouth has clarified that compostable labelled bags do perform differently to those marked biodegradable or oxo-degradable when it comes to decomposition in water and soil, and overall impact on the environment.
It is vital to make the distinction between biodegradable, oxo-degradable and compostable, as they mean very different things with different implications for their respective end of life scenarios.
As the research makes clear, ‘biodegradable’ is a term that has no official definition or requirements, often misleading brands, retailers and consumers. Meanwhile, oxo-degradable have been outlawed by the EU commission, due to their contribution to the micro-plastics problem.
On the other hand, the term compostable means products are capable of complete biodegradation in compost and must meet specific standards for breakdown to receive a compostability certification.
As the research found, biodegradable products were discovered to persist in the environment with minimal degradation of quality after 3 years, while compostable products broke down (or completely disappeared) much quicker, even when not placed in the ideal composting conditions.
As the packaging industry is going through a period of radical transformation and transition to ‘sustainable’ packaging materials, accuracy regarding the issue of degradation is more vital than ever. This research is an important opportunity to differentiate between compostables, which live up to their end of life claim, and biodegradable, which can be seen as misleading.
In any case, innovators in the industry alongside TIPA, strongly believe that no material should wind up in marine water, litter open fields nor end up in a landfill.
Compostable packaging is certified to decompose within a few months in a home or industrial facility. Governments should collaborate with businesses on achieving a circular economy for plastic packaging, and ensuring the right infrastructure methods in place for each plastic packaging stream. This is the only way in which we can achieve the Global ambitious goal of all plastic packaging being reusable, recyclable or compostable by 2025.
Confusion is still bigger, why oxo-degradable? The study does not test oxo-degradable products but oxo-biodegradable products, two different technologies. One may be banned in EU the other not.
There is an ongoing study by ECHA on oxo-biodegradable products, and till now no negative conclusion has been published, and specially no references to microplastics.
Once again, we see a need from the compostable plastic producers to mislead the public in general lying.
The study even if not complete, is clear in the conclusions, compostable or biodegradable products labeled 14855 or 13432 do not perform better than conventional plastic if left in the open air/water/buried. For information 14855 is one of the tests of 13432.
“compostable or biodegradable products labeled 14855 or 13432 do not perform better than conventional plastic if left in the open air/water/buried”
…but surely (?!) the compostable product contains no plastic and is hence better for the environment in the longer term, even if not composted “correctly” ? Or have I, like others, mis-understood or been misled ?
Most flexible compostable plastics made from formulations based on
thermoplastic starch and biodegradable synthetic polymers – known as starch blends strach, contain a fossil based aliphatic-aromatic copolyester to give them strengh. The ratio is between 30 and 40%. This polyester is added to increase the strenght and fexibility of the biobased material.
BASF is one of the major producers of this polyester, it is called Ecoflex.