Degradable PET controversy
Another material receiving lots of attention, degradable PET, sounds like an ideal choice for green packaging because so much
PET packaging ends up as litter, ocean pollution, or in landfills. Three trade associations have reservations about this PET,
which includes additives to make it degradable. The associations fear that the material could cause problems for PET recycling
and recycled-content PET products.
NAPCOR contends that suppliers of degradable PET need to substantiate claims of degradability, investigate the effect of degradable
additives on the quality of the PET recycling stream, examine the effects of degradable additives on products made of RPET,
and learn how the material changes the service life of these products.
"We don't yet understand the impacts that these additives could have on the quality of the PET recycling stream, let alone
the impacts on the safety and functionality over time of next-use PET products like recycled-content PET packaging, carpeting,
or strapping," explains Sabourin.
EurPR (Brussels), a trade association for plastics recyclers, echoes NAPCOR's concerns and is particularly worried about whether
oxo-biodegradable PET will pose problems in recycling operations.
European Bioplastics (Berlin) also has issued warnings about oxo-biodegradable plastic containers, claiming that no evidence
shows that these materials meet international standards regarding biodegradation and compostability such as the International
Organization for Standardization's ISO 17088 Specifications for Compostable Plastics or European Norm 13432 Requirements for
Packaging Recoverable through Composting and Biodegradation. "If certain products that claim to be biodegradable or compostable
are proven not to fulfill acknowledged standards, this is liable to impact negatively on our own members' products, even though
they do fully comply," explains Andy Sweet-man, chairman of the board of European Bioplastics.
But a maker of oxo-biodegradable additives argues that its material complies with the degradability, biodegradability, and
nonecotoxicity requirements of the American Soceity for Testing and Materials's D6954-04 Standard Guide for Exposing and Testing
Plastics that Degrade in the Environment by a Combination of Oxidation and Biodegradation (Symphony Environmental Technologies,
London).
Another maker of a degradable additive also claims compliance with ASTM standards for biodegradability and recyclability and
has confirmed results with third-party testing and validation. This additive is not classified as oxo-biodegradable, but enables
the PET to degrade in anaerobic and aerobic environments by attracting microbes that convert the resin into humus and gases
such as carbon dioxide and methane. Because it does not chemically bond to the PET, it reportedly has no effect on bottle
weight or properties. Testing also has shown that the material has no negative effect on the PET recycling stream (EcoPure
degradable additive for PET, ENSO Bottles, Phoenix, AZ).
Hallie Forcinio is Pharmaceutical Technology's Packaging Forum editor, 4708 morningside Drive, Cleveland, OH 44109, tel. 216.351.5824, fax 216.351.5684, editorhal@cs.com
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