No, biodegradable plastic does not just disappear by itself

Part of a series of business columns in Danish newspaper Fyens Stiftstidende
Author: Camilla Haustrup Hermansen, Director of Business Development
Published: 28.07.2019

There is a question which almost always comes up when the conversation is about plastic. That is regardless of whether I am attending a work meeting or I am together with friends and family. Is packaging made from biodegradable plastic environmentally friendly? Unfortunately, there is only one answer, and that is no.

The answer disappoints most people who sincerely want to make a positive difference in their daily lives, and I understand that. As a private consumer I too share this disappointment. It would be wonderful if all plastic packaging that has gone astray and ended up in nature would just disappear. That would be neither more nor less than a dream scenario – and that is exactly what it is. As a professional I can make it clear that plastic cannot disappear by itself.

I greatly appreciate that the idea of biodegradable plastic is an attractive and easy solution to buy into. The idea has close ties to the happy consumer’s everlasting dream of the good bargain that satisfies needs, while neither leaving traces nor causing undesirable, negative consequences. In the retail and food industry this dream is probably about a competitive packaging material which can degrade itself after use, thus minimising any risk of polluting the environment. Imagine if any physical evidence from our collective overuse of plastic would disappear as if by magic. Poof. No matter how good it may sound, it is not realistic to believe that packaging made from biodegradable plastic is good for the environment per se.

The reality is that biodegradable plastic does not fit into the waste system in Denmark. The Danish waste system is not designed to handle composting, and therefore no one can benefit from the biodegradability of a plastic material. Moreover, biodegradable plastic cannot be recycled together with other plastic types and it contaminates food waste. Therefore, biodegradable plastic should not be used for packaging.

My experience is that there is a general confusion regarding the advantages and disadvantages of the use of biodegradable plastic. It is important to distinguish between products which are used in private households, and products which are used for industry-specific purposes in professional gardening, for instance. My focus here is packaging for private consumers which is an area where biodegradable plastic has no place.

Back in May two British researchers from the University of Plymouth created headlines in the media when they presented the results of their study of biodegradable plastic. The researchers had set out to investigate what happens to different types of plastic bags over time, including both compostable and biodegradable plastic bags, when they are exposed to three different natural environments. The bags were therefore buried in the ground, sunken into the sea, thrown to the ground and exposed to natural weather. The results showed that after three years the plastic bags were still intact and could easily be used as carrying bags. The most startling part was that the biodegradable bag still looked like a bag and could carry up to two kilograms of groceries.

In the wake of this news, experts from the University College in London have raised criticism of companies that sell other types of products such as eco-friendly cutlery or diapers. They were criticised for not informing consumers about the fact that it requires an industrially controlled process in a hot and humid environment at approximately 60 degrees Celsius to degrade these products. In other words, it is a process that is impossible to recreate in the compost pile along with the rest of the bio or garden waste.

For the same reason, several experts have also argued that it is misleading for consumers when companies promote plastic packaging as compostable or biodegradable. The vast majority of the so-called biodegradable plastic packaging actually cannot be decomposed naturally – in fact it carries the risk of polluting the environment even more. According to the Danish Waste Association, products such as packaging, disposable cutlery and coffee capsules made from biodegradable plastic are on the “no-no list”.

The fact is that we experience problems with getting rid of the biodegradable plastic in Denmark, since few recyclers want to buy this kind of waste and apply it in their reprocessing plant for bio waste. In Germany, they even have a law for waste and fertilizers that prohibits biodegradable plastic in the treatment of biological waste. Therefore, the recommendation here in Denmark is clear: biodegradable plastic must either be utilised for energy, i.e. incinerated, or a new recycling solution must be developed for exactly this kind of plastic waste for when it is sorted along with other plastic packaging.

The important thing here is that there are certainly several alternatives to traditional plastics. However, none of these can be considered actually sustainable before they are supported by an infrastructure in the society which can contribute to ensure large-scale production as well as collection and recycling. In Denmark this is far from the reality today, when it comes to biodegradable plastic.



Plastic is not just plastic

Biodegradable plastic is produced with bio mass, oil and gas or a mix of these. It is used as for instance gardening foil which is certified to be composed in the soil.

There are no EU standards for biodegradable plastic.

Bio-based plastic is used in for instance soft drink bottles and can be recycled as traditional plastic.

Consumers cannot distinguish between traditional plastic and biodegradable plastic or bio-plastic at first glance. Typically, the plastic types are perceived as one in their clarity and quality, no matter what type of plastic it is.