Technological watch

Perspective: The Materials Wars: Is plastic actually better?

Plastic containers and packaging continue to be a hot-button issue in corporate social responsibility campaigns. Yet some companies are making the switch to plastic. Surprised? Companies are learning that plastic can often be the most sustainable choice.

Coca-Cola — selling about 1.8 billion drinks per day — prefers to stick with plastic bottles to reduce the company's carbon footprint. Snapple and MillerCoors have made the switch from glass to plastic. Pepsi has introduced a bottle of 100 percent recycled PET plastic for its LIFEWTR product.

"Using PET instead of glass can provide sustainability benefits, for example by reducing the weight of packaging and associated carbon emissions from transport," says worldwide drinks company Diageo.

For years, activists have been simplistically advocating for glass, aluminum, cartons and biodegradable materials for packaging.

Glass, though recyclable, requires more energy to produce and ship. A new study from the United Kingdom ranks glass last when comparing the environmental impact of commonly used materials.

Aluminum, also considered an eco-friendly alternative, requires a mining process that has long-term negative effects on local communities and the environment, long after mines have been shut down. The production of aluminum releases twice as much carbon into the atmosphere in comparison to plastic.

Then there are the cartons (think: boxed wine). While lighter than glass, the glued combination of plastic, aluminum and cardboard to create the packaging and lining makes these products more difficult to recycle than other materials.

Biodegradable packaging, meanwhile, is growing in prominence. It appears at first glance to thread the needle. It keeps some of the same benefits as plastic (lightweight, flexible), while supposedly eliminating a downside (lack of biodegradability).

But the reality is not up to the promise. They may biodegrade in controlled conditions, but in nature and marine environments, biodegradable materials can take years to decompose.

Corn-based plastics (polylactic acid) are being used by some foodservice companies. When placed in landfills, with no oxygen present, degrading bioplastic materials release methane, a greenhouse gas 23 times more troubling than carbon dioxide.

In order for corn-based plastic to live up to its "biodegradable" moniker, the composting process requires extreme heat and controlled moisture levels — not found in a landfill or the ocean.

Another practical issue is that many consumers will toss this plastic in the recycling bin. Plant-based material needs to be handled separately. Mixing it in with conventional plastic will actually contaminate the recycling process, creating more waste by sending other perfectly recyclable items to landfills.

And not all conventional plastics are the same. Taco Bell switched in 2018 to using clear polypropylene plastic cups because it is more recyclable. PET and high density polyethylene are accepted in almost all curbside programs, and polypropylene is also commonly accepted.

Other plastic resins including polystyrene — what Taco Bell previously used for cups — are not nearly as recycled and typically wind up in a landfill.

PS packing peanuts are another plastic that companies are rejecting. Instead, many are using more recyclable fillers including paper, cardboard pads and partitions, and even starch-based peanuts that dissolve in your kitchen sink.

There's no one-size-fits-all approach to packaging. Companies should aim to increase the recyclability of their products. Factors, including greenhouse gas emissions in production and transportation, should be considered. Ultimately, a pragmatic approach, not a dogmatic one, is the best way to support sustainability.

Will Coggin is managing director of the Essential Plastics Coalition. Learn more at EssentialPlastics.org.

Publication date: 19/03/2021

Plastics News - packaging



      

This project has received funding from the Bio Based Industries Joint Undertaking under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 837761.