Biodegradable, Degradable and Compostable - What is the difference?

Degradable. Biodegradable. Compostable.

What does it all mean and what's the difference anyway?

making greener choices

Many of us are interested in making greener choices but with so many terms and that all mean different things, we thought we’d explain just what these terms mean. 

Read through to discover the difference between degradable, biodegradable and compostable and how you can make informed choices. 


Degradable simply means that something will break down into smaller pieces. It can be oxo-degradable (degradable when exposed to air) or photo-degradable (degradable through exposure to light).

One of the common areas we find this in green-washing is on supermarket bags. These are simply a conventional plastic bag that has been treated with special chemicals that make it fall apart when exposed to air and sunlight.

All this really means is that smaller pieces of plastic are produced that end up in the environment and can be eaten by wildlife. It is in many ways a far worse result as the bags do more damage to the environment when in smaller pieces. At least a complete plastic bag has more chance of being able to be picked up. 

A recent senate enquiry into the threat of marine plastic pollution in Australia found that the degradable bag option is equally as bad for the environment as regular plastic bags. They enter the food chain lower down, getting eaten by smaller species and making their way up the chain as larger species consume then. 



Biodegradable simply means that it is able to be eaten by living things like fungi, bacteria or microorganisms. For plastic bags, the most common materials that these are made from are corn or wheat starch and for other products, 

Now, this is all good and well, but there are certain conditions that must be met for the bag to biodegrade. The bag must be exposed to UV light, but more importantly, the temperature must reach 50 degrees Celsius. If biodegradable bags are sent to landfill and do not have access to oxygen, they end up producing methane, a greenhouse gas with a warming capacity 21 times more powerful than carbon dioxide. 


Compostable is a specific term given to biodegradable materials that biodegrade within a certain time frame under composting conditions.  These time frames and conditions can vary depending on the country but as a general rule, it means that the products will break down within the typical commercial composting cycle of 8 weeks, aided by movement of the soil and high heat. 

Compostable is the gold standard for all products, meaning that they are certified they will go from their current form back to the earth. Wherever possible, try to use compostable products over alternatives. 

Can I recycle biodegradable and degradable bags?

Generally, no.

All plastic bags, biodegradable and compostable bags will interfere with the recycling process if they are put in your standard recycling bin at home. 

Some supermarkets have begun offering plastic bag recycling facilities but there is a far better option, as we'll explain below. 


So, what's the solution?

The answer is so simple. Bring your own bag and you are taking a great step towards a cleaner future. Invest in a sturdy canvas bag that you can throw in your car or backpack. A set of produce bags will help when you are purchasing vegetables too. 

The future is in our hands and by transitioning from an economy based on convenience rather than taking simple steps to limit our consumption. Every action we take is a vote for the type of future we want.

Be the change you want to see in the world and make the change today. 

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