Compostable Packaging Claims Crumble in Mother Earth News Study

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Photo By Gretchen Stuart/Courtesy Mother Earth News

More and more companies are displaying the words “biodegradable” and “compostable” on plastic bags and packaging. But without much additional explanation on the products, some companies are getting away with exaggerating their products’ composting capabilities.

With the help of Woods End LaboratoriesMother Earth News put five plastic bags’ claims to the test. Bags from NovamontBioTufBag-To-Nature and Oxo-Biodegradable were composted for 25 weeks in two different composting settings.

One setting simulated commercial, large-scale composting conditions at 140 degrees Fahrenheit. The other simulated conditions in average home composts at 77 degrees Fahrenheit. The result? None of the bags fully broke down in normal home composting conditions. The Mater-Bi bag from Novamont performed the best in home conditions, and was about halfway degraded at the end of the study.

The Novamont, BioTuf and Bag-To-Nature bags all decomposed in the higher temperature composts, but the Oxo-Biodegradable bags did not begin breaking down at all, even in the higher temperature compost.

Though some companies claims are less-than-truthful, Frito Lay’s SunChips brand gives a clearer definition of its compostable bags’ capabilities. It emphasizes that its packaging will break down in a “hot, active compost bin or pile.” The average home compost doesn’t fit into the category, but the description helps consumers know exactly what they’re buying (and what they’re buying into).

More on plastic bags: 

• FritoLay and TerraCycle turn old chip bags into useful products.

• Reuse plastic bags to make a unique lampshade.