Let's Talk About Biodegradables and Compostables

Written by Elizabeth Smith

Are you, like me, confused by the meaning of the word biodegradable? Do you wonder how that word differs from the word compostable?

Most of us think the two words are interchangeable. And most of us think that a product with a biodegradable icon on it means it will quickly and effortlessly decompose back into the earth. A good thing, right?

Digging a little deeper, I have learned that the terms biodegradable and compostable are not synonymous. And my comfortable belief that compostable products would easily return to the earth has been shattered. 

To make it easier, I’ve compiled a list of related words and a short definition of each, to try to make your understanding a little easier, as well.

Read the small print  Industrially Compostable

Read the small print Industrially Compostable

Biodegradable. These plastics are essentially the same as conventional petroleum-based plastics, but with the addition of many chemicals that give them the capability to break down under the right conditions. There is no legal definition of this word. If a product is designated biodegradable, it means that, over an unspecified period of time, it will break down. But unfortunately, that timeline is undefined and not held to any specific standard. The plastics industry often claims their products are biodegradable, which they well may be, if you are talking centuries. To further muddy the waters, not all biodegradable products are compostable. In order for those products to break down, they need to be exposed in a controlled manner to the proper degree of heat, humidity and sunlight.


Compostable. There is a legal definition for this word. A compostable material is one that breaks down fully (leaving no visible, distinguishable or toxic residue) in a specific amount of time and under certain conditions. The American Society for Testing of Materials sets the standards for compostable materials and products. All compostable materials are biodegradable. 


Landfill. Biodegradable products simply placed in landfills don’t break down easily. If they do not receive proper chemicals, light, oxygen and heat, they become entombed with all the other trash dumped into landfills, where they remain for great lengths of time in an anaerobic state, releasing methane, which contributes to problems related to climate change. According to Scientific American “methane warms the planet by 86 times as much as CO2, according to the Intergovernmental Panel on Climate Change.

Recycling Facilities. Biodegradable products cannot go into regular recycling facilities. Due to all additives used to create biodegradable products, they are not as durable and can actually contaminate regular recyclable products, causing them to be non-recyclable. 

Standard Composting. Standard composting does not provide adequate heat, light or humidity to break down biodegradable plastic. And even if it could, the chemical additives in biodegradable products would then be released into the soil, creating an entirely new problem. 

Commercial Composting Facility. If you look carefully at your biodegradable coffee cup, you might see, in very tiny print, the words, “Industrial Compostable”. Sad but true, the ONLY place where you can safely and effectively decompose biodegradable products is in one of these facilities. With only about 200 of these facilities in the US, our country is not equipped to adequately compost our current volumes of biodegradable plastic. To make matters worse, many commercial facilities reject PLA and other biodegradable plastics as they are seen as contamination risks. 

Bottom line: Until there is a system in place to properly compost biodegradable products, they continue to contribute to our global plastic crisis. There seems to be only one viable solution, and that is to reject plastic one-time-use products of all kinds, in the hope that a powerful grassroots movement will force suppliers to find solutions. If we sit idly by and do nothing, it is projected that the production of plastic will double in just one short decade, by 2030. 







Elizabeth Smith