08. Aug 2014
Mexico’s three biggest polyethylene suppliers have denounced oxo-biodegradable technology in a letter to the country’s national association of supermarkets and departmental stores, (as Plasticsnews.com published on July 31).
“We consider that the use of degrading additives is not a sustainable way of tackling this issue [of waste management], as it has not been proven indisputably that materials containing such [biodegrading] additives really do biodegrade in landfills or can be recycled. In other words, degrading additives do not add value to plastic waste, including polyethylene waste,” the letter from Braskem Idesa SAPI, Dow Química Mexicana SA de CV and Pemex Petroquímica stated.
In the letter, the trio of PE suppliers said they had written to ANTAD after becoming aware that some of the association’s members had been specifying the use of oxo-biodegradable additives in their PE shopping bags and packaging.
“We believe that, together with the use of said additives, a message is being spread that [oxo-biodegradable technology] is environment-friendly, which confuses and deceives society and consumers, inducing them to dispose of waste inadequately, thus damaging the environment and efforts to recycle the material,” the letter’s authors wrote.
They added that on April 16 the European parliament voted in favor of modifying directive 94/62/EC on packaging waste and which urged member countries to “drastically reduce materials that contain oxo-biodegradables to the point where they are eliminated altogether.” (Source plasticsnews.com / MT)
bioplastics MAGAZINE asked suppliers of such additives again and again to provide scientifically backed evidence. We did not receive any proving a complete biodegradation. They show mechanical fragmentation and some biodegradation (proven by the generation of CO2)... But this ends and 30 or 40 % in a Plateau. Then they extrapolate and say "eventually it will completely degrade". But such extrapolation is not allowed.
As soon as we receive scientifically backed evidence and test results from an independent lab showing complete biodegradation by the generation of CO2 in a given timeframe under controlled conditions), we'll be happy to publish these results.
For further information you can also have a look in some publications in bioplastics MAGAZINE, such as
Biodegradability - Sorting through Facts and Claims
by Prof. Narayan (among others: Distinguisehd professor, Michigan State University)
by Prof. Scott (among others: Chairman of the Scientific Advisory Board of the Oxo-biodegradable Plastics Association)
Editor's note (#2, 02 Sept. 2014)
Michael Stephen, Director of Symphony Environmental Ltd (producer of OXO-Additives, asked us to publish a response to the letter mentioned above.
Please find his response here.
Please also note, that we (bioplastics MAGAZINE) do noit consider this or any of the documents or publications in this letter as a scientifically backed evidence.
OWS comes to the following conclusion:
From the above results (cited in Michael Stephen's response) obtained by Jackubowicz, but also based on the results obtained by Chiellini in the past years, onecouldassume that biodegradation of oxo-degradable plastics in soil happens at a (much) higher rate when compared to compost. However, other publications, including those of Fontanella and Husarova, show the opposite. Furthermore, as compost, certainly in case of industrial composting,which is performed at elevated temperature,can considered to be more aggressive when compared soil, one would expect higher biodegradation rates in compost instead of in soil (just as with biodegradable plastics). In other words, there is aninconsistency in the biodegradation results obtained for oxo-degradableplastics.