Polystyrene packaging has fewer negative impacts on the environment than other popular disposable takeaway food containers, however, because it isn’t currently recycled, it cannot be considered a sustainable packaging option.
That’s the findings of researchers from Manchester University's School of Chemical Engineering and Analytical Science who have carried out the first ever comprehensive study of the environmental impacts of disposable takeaway-food containers. They looked at aluminium, polystyrene (styrofoam) and polypropylene (clear plastic) containers and compared them to reusable plastic containers, such as Tupperware.
They found that polystyrene was the best option among the disposable containers across all the impacts considered, including the carbon footprint. For example, it has 50% lower carbon footprint than aluminium and three times lower than plastic. This is because of the lower amount of materials and energy used in the production of polystyrene compared to the other two types of container.
However, because it isn’t currently recyclable, scientists cannot consider it a sustainable packaging option.
In comparison, the study found that reusable Tupperware containers had a lower carbon footprint than disposable polystyrene when they were reused more than 18 times. This is despite the energy and water used for their cleaning. Disposable clear-plastic containers needed to be reused even fewer times – only five – to become better for the carbon footprint than the polystyrene.
Professor Adisa Azapagic, the project leader, commented: “As consumers, we can play a significant role in reducing the environmental impacts of food packaging by reusing food containers as long as possible. Our study shows clearly that the longer we reuse them, the lower their impacts become over their extended lifetimes.”
The study used life cycle assessment (LCA) to estimate the impacts of containers, taking into account their manufacture, use and end-of-life waste management. Altogether, the research team investigated 12 different environmental impacts, including climate change, the depletion of natural resources and the toxic effect on ecosystems.
The study estimates there are 2025 million takeaway containers per year being used in the EU alone. It also says finding a way to recycle disposable takeaway containers could help reduce equivalent greenhouse gas emissions generated annually by 55,000 cars.
The global takeaway food market is growing fast, with a projected value of over £80 billion in 2020.