Biodegradable and compostable materials are gaining in popularity. Biodegradable packaging materials can be broken down by microorganisms (bacteria or fungi) into water, methane and CO2. This process is strongly dependent on the environment: temperature, the presence of microorganisms and the presence of oxygen and water. It should be noted that biodegradable and compostable materials do not necessarily offer environmental benefits for all applications and waste processing systems.
Compostable packaging materials are materials that meet the requirements of the EN13432 standard. When packaging materials and disposables are EN13432 certified, they may carry a seedling and/or OK Compost logo. These logos indicate that the product can be composted in an industrial environment.
The Belgian certification OK Compost is found on bags, sleeves and trays made of compostable plastic. Only compostable organic waste bags (bearing the OK Compost or Seedling logo) may be disposed of in the green organic waste bins. Other compostable packaging materials and compostable products, e.g. single-use cutlery and trays, should be disposed of as residual waste. This is because it is unclear whether the lead time in the industrial composting facility is long enough to properly break down the compostable plastics. In one's compost heap at home, such materials are also not broken down efficiently. The organisation AIB Vinçotte issues the certification and is also responsible for auditing manufacturers.
Considerations for composting
- When a packaging is badly contaminated with organic material, processing it in the compost stream can be the optimal solution.
- Compostable packaging materials can be used to make the collection of organic waste streams easier. Think of e.g. the bag inside a compost bin.
- Compostable packaging materials can lead to confusion among consumers with regard to the correct disposal method and the perception of sustainability. When these materials end up in the plastic waste stream, they can disrupt the plastic recycling process.
- Biobased and compostable materials are generally more expensive that conventional packaging materials.
Biodegradable versus biobased
Biodegradable packaging materials are not the same thing as biobased packaging materials. Biobased materials have a direct or indirect natural origin, e.g. paper and wood. There are also various types of plastic that are made from biobased raw materials, such as sugar from sugar cane and sugar beets.
In general, biodegradable packaging materials can be broken down in industrial composting facilities if they meet the EN 13432 standard. This is an international standard for biodegradable packaging materials which states that these packaging materials break down quickly enough in industrial composting facilities and are therefore degradable. The EN 13432 standard is based on a decomposition process for biodegradable plastics of no more than twelve weeks at a temperature of circa 60 degrees. Biodegradable plastic packaging materials that meet the EN 13432 standard can be recognised by the Seedling logo or the OK Compost logo.
In recent years, however, the processes used at composting facilities have been optimised and significantly shortened. On average, the decomposition period is just two to four weeks. The question is therefore whether the EN 13432 standard is still relevant to modern-day practice, in which composting facilities utilise much shorter lead times.
Contrary to what many people believe, biodegradable plastics are currently not degradable in nature. The use of biodegradable packaging materials therefore does not offer a solution for the litter problem or the plastic soup.
Separate collection and processing
The costs of organising separate sorting and recycling processes are high and separate processing will only pay off if the stream of material is large enough. At the moment, separate processes are only organised for streams of packaging materials from businesses or for streams that are manageable and large enough, such as the PLA drinking cups that are used at festivals and disposed of on site. In that case, all used cups can be recycled or fermented separately after the festival.
Situation in various countries
The National Waste Management Plan 3 (LAP 3) indicates that there are still some practical issues with regard to the composting of biodegradable plastics and that a policy statement concerning the use and processing of, among other things, biodegradable plastic is being developed. In accordance with LAP 3, biodegradable plastic packaging materials should currently not be disposed of as organic waste, not even if they feature the Seedling logo or the OK Compost logo. The only exception are the biodegradable plastic bags that are used for the collection of organic waste.
The waste stage
The use of packaging materials is subject of European legislation. On 20 December 1994, the European Parliament and the Council of the European Union introduced the Directive 94/62/EG (hereinafter: Directive) for packaging materials and packaging waste. This Directive was subsequently revised on 22 May 2018. The goal of this Directive is to limit the use of packaging materials and stimulate recycling, reuse and other useful applications for packaging waste.
All EU Member States are required to implement the Directive in their own national legislation. Every Member State has its own way of doing so. Packforward started to give an overview of the way the different Member States implemented the Directive, but the overview is not completed yet. You can find more information for the Netherlands, information about other countries will follow soon.
Despite the efforts made with regard to collecting, sorting and recycling packaging waste, new raw materials will have to flow into the packaging chain in order to safeguard the quality of the material and compensate for the loss of material in the chain. For a growing number of the new raw materials, steps are being taken towards a circular economy, e.g. by making use of biobased materials.