Researchers from the University of Manchester discovered that although Styrofoam containers have been assigned the lowest carbon footprint (50% lower than aluminum containers and three times lower than plastic containers), they are not categorized as sustainable packaging because Styrofoam is typically not recycled in significant amounts and is generally destined for the landfill.

To conduct what they are calling the first-ever comprehensive study of the impact disposable takeout containers have on the environment, researchers concentrated on disposable containers made of aluminum, clear plastic (polypropylene) and Styrofoam (polystyrene), comparing them to reusable containers like Tupperware.

Researchers concentrated on life cycle assessment (LCA) to approximate the impact of containers, looking at factors such as manufacturing, usage and end-of-life waste management. In total, the team examined 12 different environmental impacts, including marine ecotoxicity, climate change and depletion of natural resources.

Based on that data, researchers concluded that polystyrene containers had less of an environmental impact than the aluminum and plastic container options due to using fewer materials and expending less energy during its manufacture than the other materials. Yet, without a clear and current polystyrene recycling policy in place in the EU, it is not a sustainable packaging option.

Lead author Alejandro Gallego-Schmid, Ph.D., explained: “Achieving this level of recycling of styrofoam [sic] containers is going to be challenging. Although technically possible and practiced at small scale in some countries, the main difficulties are related to collecting the used containers and the associated costs.”

Joan Fernandez Mendoza, Ph.D., and one of the study authors, added: “Because they are so light, the styrofoam containers can easily be blown away, contributing to urban and marine litter. So, despite their lower life cycle environmental impacts relative to the other containers, styrofoam [sic] containers cannot be considered a sustainable packaging option unless they can be recycled at a large scale.”

Considering that an estimated 2.025 billion takeout containers are used and discarded in the EU per year, never mind other parts of the world, Manchester University scientists believe that recycling such waste might be the equivalent of reducing greenhouse gas emissions by roughly 55,000 cars each year. However, If EU goals for recycling are met by the year 2025, recycling half of the containers currently in use might lead to a one-third reduction in the carbon footprint.

The study is published in the Journal of Cleaner Production.