Compostables

One of the problems associated with compostable plastics is consumer confusion around different types of compostable plastics.

The perception very often is that all “Compostable Plastics” will naturally biodegrade in a short, defined period of time. This is not always the case, however.

Very often “Compostable plastics” need to be chemical treated to stimulate the decomposition process or must be exposed to very specific environmental conditions (e.g. temperatures, moisture levels) for the process to begin.

Quick Guide Terminology

Polymers

They are the conventional plastics, complex organic compounds capable of being moulded, extruded and cast into various shapes and films. Polymers are most commonly fossil-fuel based and non-biodegradable.

Biopolymers

Aka Bioplastics, the biopolymers are derived from renewable materials such as polylactic acid, corn or cellulose. The environmental dividend lies in the production process. These may or may not be biodegradable. Non bio-degradable plastics can be recycled alongside regular plastics.

Bio materials

Are material made from plant fibres, wood pulp, cellulose, corn or lactic acid, that composts within 12 weeks (if correctly processed). These cannot be recycled alongside regular plastics.

Home Compostable

Plastics that will naturally decompose into organic materials in an ordinary garden compost tray or a compostable bin (brown bin) within a short period- for example, less than 40 days.

Pros

  • Compostable plastics are perhaps the most consumer friendly option; particularly home compostable options. The concept is easy to understand and managing waste is relatively simple.

  • Logistically, home compostable packaging does not require collection and processing.

  • The quality and reliability of compostable plastics has improved considerably in recent times making them more attractive for packaging.

  • Viable Home Compostable plastics are available immediately and do not require the support infrastructure of recycled plastics- empowering consumers to make responsible environmental choices right now.

Cons

  • Compostable plastics are single use plastics. As such the energy used in its production is lost in composting giving compostable plastics a higher carbon footprint than successfully recycled plastic.

  • Compostable plastics are expensive relative to conventional plastics and can contribute to price inflation.

  • Mixing compostable plastics with recyclable plastics can contaminate the recycling process and render the recycled plastic useless.

  • The EU has committed to developing a Circular Plastics Economy strongly focused on recycling. Compostable plastics alone cannot deliver on the ambitious targets set by Member States and should be viewed as complementary to the evolution of recycling infrastructure to support the recycling of plastics.