Biodegradable vs Compostable: What’s the Difference and Why It’s Important
Updated: Nov 8, 2021
People who try to live a sustainable lifestyle have a special eye for labels. Vegetarian, vegan, recyclable, biodegradable, compostable - some are precise, some are vague, but all of them make us feel a little better about our purchases. And rightfully so!
But even similar terms can have some crucial differences which determine how much we are helping or harming the planet. That’s exactly the case with biodegradable and compostable. Although these terms overlap, it is important to distinguish them. So let’s break it down! (no pun intended)
At first glance, the definition of biodegradability may seem quite simple. “Bio” part hints that such a product can naturally break down with the help of bacteria, fungi, or other biological processes.
That’s a good start, isn’t it? However, there are many details to take into consideration. Practically, nearly everything can degrade and fall apart. Even well-known polluters such as plastic or diapers will eventually break down, but it could take hundreds of years.
Therefore, time is an important criterion to consider. A product or material can be considered truly biodegradable if it can quickly break down into harmless particles with no human intervention. “Quickly” can be defined differently, but anything up to a year is usually satisfactory. If it takes more time, it’s degradable, but not biodegradable.
Another aspect to consider is how well can a material break down. For instance, plant-based plastic is usually considered biodegradable. While it can break down naturally, it relies heavily on environmental factors such as temperature and humidity level. In unsuitable conditions, it will lose its ability to degrade quickly and will be as harmful to the environment as regular plastic. Since biodegradation is an unsupervised sensitive process, in some cases materials can also leave toxic waste behind.
As a rule of thumb, every plant-based, animal-based, or natural-mineral based product is biodegradable. Many people are not aware of that and assume only food and plants are biodegradable, but in reality, the list is much longer. Even though they take more time to break down to a microscopic level, such things as paper bags or cardboard boxes can be biodegradable as well.
In a way, composting is a special type of biodegradation that is done by humans and can only be applied to organic products. Unlike biodegradation that can leave toxic residue, the end result of composting is actually useful for the environment. Compost, decomposed organic waste, can be used as a fertilizer.
Although the terms are often confused, compostable materials aren’t always biodegradable and vice versa. Compostable products will not necessarily break down quickly unless they are placed in specific conditions. On the other hand, in a special composting environment with certain air, sunlight and air conditions, they will break down in less than 90 days and leave no harmful residue.
Compostable materials are a great way to not only minimize the harm you do to the environment but also improve the conditions of the soil. By supplying it with nutrients, compost improves the soil’s structure and water retention thus aiding plant growth. Although composting in industrial conditions is extremely important, doing it at home is also a good step towards a more sustainable lifestyle. Many house owners make compost piles in their backyards, but there are compact indoor solutions for apartment owners as well.
What’s the difference?
While composting is a relatively easy-to-understand concept, biodegradability doesn’t have a universal legal definition. That’s part of the reason why the terms are confused so often.
Whether we can consider something biodegradable largely depends on the time it takes to break down. That, in turn, is defined by the conditions in which the process takes place. But in some cases the process is unsupervised, so there’s no control over it.
Composting is, essentially, optimized biodegradation. It creates perfect conditions so that products can break down in a fast and non-toxic manner. However, not every biodegradable product can be composted. A product not suitable for composting can take longer to break down, which can disrupt the composting cycle.
Finally, the term compostability refers to the product’s ability to be turned into compost and thus help the environment in a short amount of time. Biodegradability, on the other hand, only means that in the right conditions the material can quickly degrade through a biological process.
Why does it matter?
Both these terms are used to label the products that are designed to do less harm to the environment. However, misunderstanding of what they mean can bring dangerous consequences. The biggest mistake we make is assuming that just buying such a product will make a difference. In some cases it might be true - the production of biodegradable products is usually more sustainable, but the promises these terms bring can only be fulfilled if we discard the products properly. So it’s the consumers’ responsibility, not the companies’.
Due to the amount of trash and low oxygen content, landfills can have horrific conditions for biodegradation. In such an environment biodegradation will happen anaerobically, meaning it will produce methane gas, which is 25 times more potent than CO2. So, if you don’t take your time to dispose of your biodegradable waste in an optimal way, the label will completely lose its meaning and benefits.
Similarly, a compostable product is a product that can and should be composted. But you have to make sure it happens! Check the labels to see if your product is suitable for at-home composting or needs to be taken to a facility. Unfortunately, there’s still not enough composting infrastructure and you might not have one nearby.
To wrap it up, a compostable or biodegradable product can be just as dangerous as any other product. There are many caveats in how such products should be handled, so make sure to read the labels and, of course, reduce and reuse. Don’t get carried away by eco-friendly labels. If you don’t make sure to appropriately dispose of compostable and biodegradable products, they are nothing more than a feel-good marketing ploy.