Use of Biodegradable Plastics “Well-Intentioned but Wrong”, Warns Top Scientist

A leading authority on environmental issues has warned that the use of biodegradable plastic should not be seen as a long-term solution or sustainable replacement to traditional plastics. In a UN report released last month, the body’s chief scientist at the Environment Programme said that the use of such bags was “well-intentioned, but wrong”.

An uphill battle against a growing problem

The ever-accumulating amount of plastic which finds its way into our oceans is of increasing concern, affecting all manner of marine life. Birds, fish and other creatures ingest the plastic, which leads to gastrointestinal difficulties and can cause starvation and death.

Several years ago, many companies sought to circumvent the problem by creating a biodegradable alternative. Supermarkets and shops were encouraged to adopt the biodegradable options for carrier bags in order to cut down on the amount of plastic ending up in the sea. However, there have been problems with the idea of a “biodegradable” plastic since the outset.

Back in 2011, the EU Commission highlighted the discrepancy between biodegradable and compostable, pointing out that the two terms are not interchangeable.

“In the current practice, a packaging product is acknowledged to be biodegradable if it biodegrades in industrial composting facilities in controlled conditions. However, a product that is compostable in an industrial facility will not necessarily biodegrade in natural conditions in the environment,” the Commission said. “Advertising a packaging product as biodegradable when in fact it will not biodegrade in natural conditions can be misleading for the consumer and can contribute to the proliferation of littering of products that will
persist in the environment.”

Biodegradable plastic often not available for recycling

Meanwhile, a more recent study conducted by the Heidelberg Institute for Energy and Environmental Research found that such bags offered little to no ecological benefits over traditional plastic carriers.

This is largely because although the bags do compost, the time necessary for this process to take place makes it unfeasible in an industrial composting plant. At the same time, it can’t be recycled along with other plastic materials, since the variation in their composition would contaminate one another. As such, these bags are generally burned in thermal incineration plants.

Now, the UN’s chief scientist Jacqueline McGlade has lent her voice to the argument against biodegradable plastic, claiming that despite their compostable nature, they are unlikely to end up in conditions conducive to disintegration.

“"It's well-intentioned but wrong,” McGlade told the Guardian. “A lot of plastics labelled biodegradable, like shopping bags, will only break down in temperatures of 50°C and that is not the ocean. They are also not buoyant, so they're going to sink, so they're not going to be exposed to UV and break down.”

Instead, the solution lies in reduced use of plastics, improved waste collection and a comprehensive recycling infrastructure.