21st of April 2017Composting & recycling

Why we don't use biodegradable plastic additives

If you've ever tried to make an eco-friendly choice when it comes to packaging materials, you'll know it can be a confusing landscape to navigate. With various claims and technical terms, it's important to be on the lookout for unscrupulous marketing. As for plastic products, the most common (misleading) claim is plastics labelled as ‘degradable’, ‘biodegradable’ or even ‘landfill degradable’. Unlike bioplastics which are produced from renewable resources, these 'degradable plastics' are just conventional plastics derived from fossil resources with an additive that the manufacturers claim will render the product biodegradable under specific conditions. 

What’s the difference between bioplastic and plastic with a biodegradable additive?
The problem with these claims is that there is no independently verified and conclusive scientific proof that the plastic will completely biodegrade. If the plastic does break down into smaller fragments that persist in the environment, they could be ingested by animals and eventually make their way up the food chain. It also does not address the problem of using finite fossil resources for single use packaging and is certainly not a solution for littering. All this does is offer consumers and brand owners a false sense of sustainability.

Regulations are in place in many countries that restrict companies from making these unsubstantiated and misleading claims. 

United Nations Environment Programme (UNEP) say:

  • “The inclusion of a pro-oxidant, such as manganese, in oxo-degradable polymers is claimed to promote fragmentation by UV irradiation and oxygen. The fate of these fragments (microplastics) is unclear, but it should be assumed that oxo-degradable polymers will add to the quantity of micro-plastics in the oceans, until overwhelming independent evidence suggests otherwise…
  • “Oxo-degradable polymers do not fragment rapidly in the marine environment (i.e. persist > 2-5 years) and so manufactured items will continue to cause littering problems and lead to undesirable impacts….”

Read the UNEP document on BioPlastics

Recyclers are also having problems when these products end up in the recycling streams. Here is what North American Recycling Industry is saying about the use of these degradable additives use in bottles, forms, and films (2013):

  • “Degradable additives that weaken products or shorten the useful life of durable plastics have a strongly negative impact of postconsumer plastics recycling
  • “APR asks those who advocate and specify degradable additives to consider the sustainability implications of degradable additives that lower the functionality of recycled postconsumer plastics when included with recyclable plastics.”

Read more from the North America Recycling Industry

The Association of Post consumer Plastics Recyclers in the US say:

  • "Since mid-2009 APR has repeatedly asked those who sell and those who use oxo-degradable or biodegradable additives to consider the sustainability implications of those additives on the recyclability of packaging
  • “The real concern is the impact of a degradable additive once the plastic is recycled and used in second and successive applications. A great deal of recycled plastic goes into carpeting, geo-textiles, strapping, plastic lumber, and pipe. All are long-lived uses. Some of these products have a 30 plus year expected life span. What happens if the polymer molecules break down during the expected service life? Failure and potentially expensive remediation likely result.”
  • “APR is reinforcing its support of legislation … that would prohibit the use of the term ‘degradable and recyclable’ on the label of a container