Biodegradable Plastic Problems

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 ‘biodegradable’, ‘oxo-degradable’ or even ‘landfill degradable’. Unlike bioplastics which are produced from renewable resources, these ‘biodegradable 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 is the difference between bioplastic and biodegradable plastic?

Bioplastics are a large family of different materials. Plastic material is defined as a bioplastic if it is either biobased, biodegradable, or features both properties.

  • ‘Biobased’ means that the material or product is derived from biomass (plants such as corn, sugarcane, or cellulose). Common plastics like PET can be made from a renewable feedstock for instance.
  • Biodegradation is a process during which microorganisms that are available in the environment convert materials into natural substances such as water, carbon dioxide, and compost (artificial additives are not needed). The process of biodegradation depends on the surrounding environmental conditions (e.g. location or temperature), on the material and on the application.
  • Compostable describes materials that are suitable for microbial treatment at end-of-life in a composting environment, whether commercial or in the home. Products or materials that pass the required standard for such microbial treatment in these environments may be verified as compostable according to the requirements of the European Standards EN13432 (biodegradable materials suitable for commercial composting) and European Standard NF T-51 800 (biodegradable plastics suitable for home composting).
difference between biodegradable and nonbiodegradable chartdifference between biodegradable and nonbiodegradable chart

Biodegradable plastics, also called “oxo-degradable plastics”,  are conventional plastics made with fossil fuel, like PE, PP or PET, and an additive (a pro-oxidant, hence the “oxo” in the name) which allegedly allows the rapid biodegradation of the product. The main problem with these claims is that there is no independently verified conclusive proof that the plastic will completely biodegrade.

Why is biodegradable plastic bad?

Biodegradable plastics are often claimed to be sustainable and better for the planet. These properties are inaccurate and misleading. Not only are biodegradable plastics made from fossil fuels, they also end up creating microplastics and contaminating other plastics recycling streams. Read on!

plastic floating on waterplastic floating on water

1. Greenwashing

The problem with oxo-degradable plastics is that they are actually known to create small fragments called microplastics, which, when ingested by animals, can eventually make their way up the food chain. All they do is offer consumers and brand owners a false sense of sustainability.

Regulations are in place in many countries that ban companies from making these unsubstantiated and misleading claims. (source>>)

plastic bottles on the beachplastic bottles on the beach

2. Harmful for the planet

In addition, there is wide-spread recognition that oxo-degradable plastics are a threat to the environment. In fact, the United Nations Environment Programme (UNEP) states:

  • “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 microplastics 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….”

(source>>)

pile of plastic bottlespile of plastic bottles

3. Contaminates recycling stream

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.”

The Association of Post-Consumer Plastics Recyclers in the US says:

  • “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.”

(source>>)

factory smokefactory smoke

4. Made from fossil fuels

Biodegradable plastics are made from oil, so they participate in the depletion of a finite fossil source of energy. Fossil fuel extraction and the plastic industry are linked to climate change and significant pollution at all stages of production. They have been found to contaminate land, water and air with chemicals toxic for all living organisms, including human beings.

(source>>)