Biodegradable vs. Compostable - What’s the Difference & Why Does It Matter?


There is a whole lot of talk about plastic these days, as films and TV programs are increasing our awareness of the scale of the plastic pollution problem.  Single-use plastics are becoming taboo, and even big brands and retailers are joining the fight against plastics.  

Or are they? 

One of my biggest bugaboos is with corporations that are simply swapping one kind of single-use packaging for another, replacing plastic with paper and calling it eco-friendly, for example.  

What consumers seem to overlook is that swapping all plastic packaging with paper is not sustainable either!  Paper production has a massive carbon footprint, and requires the consumption of a whole lot of trees, water, and energy.  Yes, paper will degrade much more quickly than plastic, but anything that is used once and thrown away is still a tremendous waste of resources, whether or not it goes on to sit in a landfill for hundreds of years to come. 

But the bigger problem I find is with the emergence of bioplastics, and the way they’re being touted as a solution to the plastic problem.  Because, guess what?  They’re not going to save us from the ongoing plastic crisis either.

Bio plastic

So, what is a bioplastic?  

A bioplastic is a form of plastic that is derived from biological substances, rather than from petroleum.  

Is it biodegradable?  

Yes it is.  

What does “biodegradable” actually mean? 

Biodegradable simply means that a substance will break down into organic matter in the right conditions, without harm to the environment.

What are the “right conditions”?  

The ideal conditions for breaking down biodegradable plastics exist in industrial-scale composting facilities, which use high heat and bacteria to break substances down into organic materials. 

Please note: just because something is labelled ‘biodegradable’ does not mean that you can just chuck it in your bin and it will break down swiftly once it gets to landfill. 

How long will it take for a biodegradable plastic to break down?

It depends on the product.  Most substances will break down eventually, but “eventually” can mean a wide range of things.  To be labeled biodegradable, a substance must be able to break down within a “reasonable amount of time”.  The time it takes most standard plastics to break down is about 1000 years, so a “biodegradable” plastic must be able to break down in less than 1000 years.  How much less?  The rules governing the term are a bit murky.  

Please note: just because something is labelled “biodegradable” does not mean that you can just chuck it in your bin and it will break down swiftly once it gets to landfill.  Nor does it mean that it will break down in your home compost bin.  It basically means that if you have an industrial composting facility in your city, and you have enough awareness to place your bioplastics in the correct bin, they will break down into organic matter without giving off harmful substances in less than 1000 years.  Super. 

Biodegradable vs compostable

In reality, the greatest advantage of bioplastics is that they allow retailers to give the impression that they care about the environment, by swapping one form of single-use plastics for another. Customers feel good about drinking their takeaway coffee in a single-use cup with a biodegradable lid, and they go on with their merry lives, free of single-use guilt.  

Compostable materials, on the other hand, will quickly break down into organic matter in your home compost bin.  Quickly means in 3-6 months (compare with “less than 1000 years”).  Compostable materials are always biodegradable.  Biodegradable materials are not necessarily compostable.  

If you must use single-use items, opt for compostable ones, but remember than any single-use material requires precious resources to produce.  The best solution is to avoid them altogether if you can.  Choose reusable containers over single-use packaging, and certainly over plastics, biodegradable or not. 


Biodegradable vs. Compostable - What's the difference and why does it matter