Based on the report of the European Comission: https://ec.europa.eu/environment/circular-economy/pdf/oxo-plastics.pdf
The European Parliament’s Directive foresees a ban on using and selling products made of oxo-degradable plastic in the EU. Unfortunately, Chinese manufacturers keep presenting their oxo-degradable plastic as biodegradable.
“In order to limit the adverse impact of such single-use plastic products on the environment, Member States should be required to prohibit their placing on the market.”
“The restrictions on placing on the market introduced in this Directive should also cover products made from oxo-degradable plastic, as that type of plastic does not properly biodegrade and thus contributes to microplastic pollution in the environment, is not compostable, negatively affects the recycling of conventional plastic and fails to deliver a proven environmental benefit.”
What are oxo-degradable plastics?
So called oxo-plastics or oxo-degradable plastics are conventional plastics which include additives to accelerate the fragmentation of the material into tiny pieces, triggered by UV radiation or heat exposure. The plastic fragments are so small that it is impossible to see them, but they remain as plastic microparticles at best in the landfill, and at worst in forest environments.
The fragmentation of oxo-degradable plastic requires oxygen. There is very little oxygen in landfills, especially in the inner parts. Evidence to date suggests that in the deeper layers of landfill – where the material has no access to a sufficient amount of air and only anaerobic degradation is possible – there is no biodegradation of oxo-degradable plastic. In the outer layers, where the material has access to oxygen, aerobic degradation is possible.
From the environmental protection perspective, the main distinction between aerobic and anaerobic degradation is that aerobic degradation produces CO2 whereas anaerobic degradation produces methane, which is 25 times more harmful than CO2.
THEREFORE, IF SOME BIODEGRADATION WERE POSSIBLE IN THE DEEPER LAYERS OF A LANDFILL, OXO-DEGRADABLE PLASTIC WOULD BE EVEN MORE HARMFUL THAN CONVENTIONAL PLASTIC FROM A GREENHOUSE EFFECT PERSPECTIVE POINT OF VIEW, BECAUSE CONVENTIONAL PLASTIC DOES NOT BIODEGRADE IN THESE CONDITIONS.
Are oxo-degradable plastics eco-friendly?
The question is whether in uncontrolled conditions in the open environment, in landfills or in the marine environment, the plastic fragments will undergo full biodegradation within a reasonable time-frame. If this is not the case, oxo-degradable plastic will contribute to the microplastics release in the (marine) environment while misleading consumers.
AS RECENT RESEARCH SHOWS, MICROPLASTICS RELEASED IN THE MARINE ENVIRONMENT GET INTO THE FOOD CHAIN AND END UP BEING CONSUMED BY HUMANS.
Recycling issues
The inherent and programmed fragmentation as intended with the oxidising additives is not desirable for many products made of recycled plastic. Oxo-degradable plastic should therefore be identifiable and separated from other plastics collected for recycling. Currently available technology can however not ensure identification and separate sorting of oxo-degradable plastic by re-processors.
TESTS HAVE DEMONSTRATED THAT THE PRESENCE OF OXO-DEGRADABLE PLASTIC IN A CONVENTIONAL PLASTIC RECYCLING SYSTEM CAN LEAD TO POOR QUALITY RECYCLATE.
Materials that are wrongly marked as ‘biodegradable’ do not end up in the proper recycling area which is bad for the recycling process of materials that are designed to be eco-friendly.
Composting
ACCORDING TO THE EU STANDARDS, OXO-DEGRADABLE PLASTIC IS NOT SUITABLE FOR COMPOSTING OR ANAEROBIC DIGESTION BECAUSE REMAINING PLASTIC AND FRAGMENTS AND MICROPLASTICS MIGHT ADVERSELY AFFECT THE QUALITY OF THE COMPOST.
Conclusion on oxo-biodegradable plastics
Oxo-biodegradable plastics are not non-polluting, eco-friendly, nor sustainable solution. Despite statements that have been made, they are broken down into very small particles that cannot be destroyed, rather than degrade to organic matter. Using certified biodegradable compost bio-films and bags is the only alternative to plastic oil-based oxo-biodegradable bags.