The association's Dennis Sabourin told CosmeticsDesign.com that companies should ask: "First, does it really work? Second, if it does, could it influence the recycling of post consumer packaging? Third, does it influence the after use life of the material? Fourth, does it affect the service life of the material?"
Using additives in PET packaging without answering those questions, threatens the whole PET recycling system, he said. "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 safety and functionality over time of next-use PET products like recycled-content PET packaging, carpeting or strapping."
Thorough testing and verification must be conducted to answer serious concerns before degradable additives should be introduced into the consumer product stream, argues NAPCOR. Its chairman Tom Busard said: "We urge manufacturers of PET resin and packaging to refrain from introductions of degradable additive-containing products until data is available for review and verification so we can better understand these products and their potential ramifications."
In 2007, US companies recycled 1.4bn pounds of PET post consumer containers.
Even if additives do facilitate the degradation of PET packaging, NAPCOR questions their purpose. Assuming that packaging will safely degrade in landfill sites or as roadside or marine litter, the value of the inherent energy used in the manufacture of plastic packaging is lost; since it is not recaptured through a recycling and re-manufacturing process.
"If packages were to disappear or fragment - and we have not yet seen evidence of this - it would not make the package sustainable, nor does it provide any positive impacts in terms of greenhouse gas emissions or resource conservation," said Sabourin. "Landfill sites are literal tombs. Degrading plastic provides no useful nutrients to the soil, and impacts to the soil and sea of reducing the plastic to molecules using degradable additives is unknown."
Meanwhile, once degradable additives begin to be used more widely, it will be difficult to stop their spread, warns NAPCOR.
Brand owners and decision-makers should not adopt degradable additives in PET packaging simply in order to be perceived to be environmentally-friendly, said Sabourin. "Don't rush to be green simply for its own sake - be responsibility green," he advised.