Is This Plastic Biodegradable?

So last week we defined the super abstract word "sustainability" but turns out there’s a whole dictionary out there of environmental concepts that are incredibly misunderstood. One of the biggest is biodegradable.


Whether it’s referring to packaging or “plastic” bags, the term biodegradable is everywhere but what is it really and, most importantly, can you compost it??

The basic qualifier of whether an item is biodegradable is that it can fully decompose into naturally occurring materials (such as water and hydrogen) in a “reasonable” timeframe. While there’s no set definition on what that timeframe is, it’s typically considered to be less than a year. There’s also no definite agreement on what full decomposition looks like.


Most importantly though, it doesn’t mention the conditions under which it decomposes, which is why most biodegradable labels are misleading at best and total fraud at worst. This is because when a lot of products say “biodegradable”, they mean under incredibly specific, controlled, energy-intensive conditions, this material will decompose.


These conditions are typically in-vessel composting operations, of which only a small minority of waste ever ends up, meaning that biodegradable coffee cup is just going to landfill and polluting the surrounding ecosystems like everything else in your bin. Those plastic bags that say compostable have the caveat of requiring a compost operation to maintain temperatures of over 70˚C for ten consecutive days to fully break-down. That is just unachievable in anything but top-of-the-line commercial facilities and definitely not your backyard container.


Now, this isn’t to say that we shouldn’t be moving towards using biodegradable materials just because they won’t end up being sustainably managed. The whole predicament is very much a chicken-and-egg scenario - composting facilities won’t be viable without demand from materials requiring them and compostable materials will be effectively useless without these facilities. The increase in use of biodegradable materials is definitely a step in the right direction but it has come with a few negative side effects.


One big problem is that whether it’s biodegradable or not, it’s still waste and most of the time it’s unnecessary waste. Even if a coffee cup is biodegradable, it still requires energy and resources to produce and will require them to break down, whereas a reusable cup can be used for years. This is applicable with most forms of packaging and similar consumer goods.


Following on from that, another issue is that using biodegradable packaging creates a false sense of doing good, which allows people to justify single-use packaging. There are very few items that truly need to be single-use, as these days almost everything has a reusable alternative that should be utilised.

The last issue was the real kicker for this blog - as mentioned, just because it says biodegradable, doesn’t mean you can put it in your compost. We obviously have our own compost here at EarthOffset and often people (understandably) put in items misleadingly labelled as compostable. It's pretty gross having to de-contaminate a three-day old bin so please stop putting those annoying PLA bags into organics collection!


We're always posting about compost and heaps of other sustainability content so if you're as crazy about it as we are make sure you're following us on our socials (Facebook, Instagram, Twitter and LinkedIn), check out our site and subscribe or reach out to us!

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Created in 2020 by Monty Compost Co