This term covers a wide range of materials, as it is not clearly defined. On the one hand, there are plastics that consist partly or entirely of renewable raw materials. These are referred to as bio-based plastics. They can be obtained from sugar cane, corn, or wood, among other sources. The majority of these bio-based plastics are not biodegradable, such as bio-PE or bio-PET. However, these materials can be easily recycled via packaging waste (yellow bag/yellow bin), as they have the same properties as their petroleum-based counterparts. Additives such as lubricants and stabilizers, which can have adverse environmental effects, are also used in the production of bio-based plastics. 

On the other hand, there are biodegradable plastics, which do not necessarily have to be made from renewable raw materials. Biodegradability does not depend on the raw material, but on the chemical properties of the substance. According to the relevant DIN EN 13432 standard, at least 90 percent of the material must have decomposed within twelve weeks. Nevertheless, these products do not belong in organic waste or on your own compost heap, as the conditions for decomposition are not met there. These plastics are also not currently suitable for recycling via the dual system, as they hinder the processing of conventional plastics. Their chemical composition reduces the quality of the recyclate (processed plastic from which new plastics are made). Biodegradable plastics sound like a good solution. At present, however, only thermal recycling—i.e., incineration—is possible.

There are also so-called oxo-degradable plastics. These consist of petroleum-based raw materials whose degradability is achieved by means of chemical additives. They are broken down by sun and heat, but not completely degraded. In principle, these plastics disintegrate into microplastics, which remain in the environment and the food chain with all the known consequences.

In direct comparison with petroleum-based plastics, bioplastics are currently neither more sustainable nor more environmentally friendly. When it comes to the ecological balance, the origin of the raw materials is particularly important, as a lot of water and additives are also required for production. The raw materials are often produced using intensive conventional farming methods, which competes with arable land for food production and leads to ocean acidification due to the high use of fertilizers. This does not offset the better CO₂ balance compared to conventional plastics, but merely shifts the problems to other areas.

Petroleum is a finite resource and should no longer be used for plastic (disposable) products if possible. Bio-based plastics have a good chance of becoming a real alternative at some point. To achieve this, the raw material should come from by-products of food production, for example, and the use of resources should be reduced during manufacturing.

We will continue to use plastics for packaging in order to transport food hygienically and safely. However, packaging used in 2020 accounted for 40 percent of total European plastic consumption (source: Brizga et al 2020), and these figures are rising due to out-of-home consumption. It is up to us consumers to decide whether this trend will continue or can be broken. The slogan "better reusable than disposable" is still valid.

Environmental tip for August 2021