What Is the Difference Between Compostable and Biodegradable?
When looking for eco-friendly products, the words “compostable” and “biodegradable” pop up a lot on packaging, whether it’s describing the packaging itself or the product inside.
Finding out the difference between them shouldn’t be so hard – especially when it seems like every company has a different definition for the same words.
The main difference between compostable and biodegradable is time. How long it takes a product to biodegrade isn’t regulated and can be as little as a few months or hundreds of years, while something compostable is regulated to make sure that it breaks down within a certain amount of time.
Is biodegradable and compostable the same thing?
The main similarity between biodegradable and compostable materials can be confusing. Something compostable is always biodegradable, but something biodegradable isn’t always compostable.
Biodegradation is a natural process where materials break down into their component parts. This can be done by bacteria, fungi, or other biological processes.
When plastic undergoes biodegradation it breaks down into carbon dioxide, water, and other components. That’s right – even plastic is biodegradable. In landfills, plastic can take many years to biodegrade, and it typically leaves toxic pollutants behind.
Compostability involves breaking the material down into non-toxic components like water, carbon dioxide, and biomass.
While it’s possible for compostable products to compost in landfills, the process is slowed down because composting needs to happen in specific conditions. These conditions involve industrial composting facilities which use high heat, airflow, and moisture to create optimum composting conditions.
Don’t get the two confused – they need to be disposed of properly!
Biodegradable materials will leave particles and toxins behind when left in compost piles, gardens, and the environment. Compostable materials will just add more mass to landfills and the composting process will be slowed down drastically.
Compostable products are typically made with plant matter, like corn starch, or are food waste, like banana skins. Biodegradable products can be natural products like banana skin or made from chemicals like plastic.
Penn Jersey Paper Company says that both biodegradable and compostable products are better for the environment than plastic products because plastic can take hundreds of years to disintegrate.
Composting might be the faster and less toxic process, but products advertised as biodegradable are still better than ordinary plastics. There are some exceptions to this though – like oxo-degradable, explained below.
It’s important to know that marketing has blurred the lines and definitions of what is “biodegradable” and what is “compostable”. Unfortunately, this has made it more difficult for consumers to work out which are the best eco-friendly products to buy.
What’s better: biodegradable or compostable?
Is one better than the other? What are the benefits and drawbacks of biodegradable and compostable products?
Let’ s find out:
Benefits of biodegradability
- Biodegradable plastics consume less energy when manufactured
- Bioplastics have reduced carbon emissions
Drawbacks of biodegradability
- Almost anything can be labeled biodegradable
- Biodegradation leaves pollutants behind
- Will take an undetermined amount of time to break down in landfills
- Still contributes to plastic pollution, especially when littered
Benefits of compostability
- Doesn’t produce toxins or pollutants
- Compostable products are made from organic materials
- Guaranteed to biodegrade in a set (and shorter) amount of time
- Made from recycled materials
Drawbacks of compostability
- When sent to landfills, compostable materials take far longer to break down
- Composting needs the right conditions via industrial composting facilities
Why compostable is better
Compostable waste is largely better for the environment when disposed of properly.
Regulations on the definition and marketing of compostable products mean that consumers can generally (though not always) be safe in the knowledge that compostable products are environmentally friendly.
While they do require industrial composting facilities, these products do not release toxic components and may even be recyclable depending on the product and materials used.
Organizations like the Federal Trade Commission do regulate what can and can’t be called compostable. Products advertised as compostable must adhere to these regulations.
The FTC’s Green Guides outline the following:
“A marketer claiming that an item is compostable should have competent and reliable scientific evidence that all the materials in the item will break down into, or otherwise become part of, usable compost (e.g., soil-conditioning material, mulch) in a safe and timely manner (i.e., in approximately the same time as the materials with which it is composted) in an appropriate composting facility, or in a home compost pile or device.”
In the Biodegradability test for packaging materials, Aryal Rabin says, “any material to be compostable should undergo testing and should meet framework of international standards which also have fixed time frame”. They also state that “the residue of the compostable materials can be used as compost and is non-toxic to the environment.”
When buying compostable products or packaging, it’s important to make sure that you properly dispose of them.
Find a local composting facility and find out how you can get your waste to them, and see what else you’re able to compost at the same time. Many will be geared towards businesses, but it’s worth finding out what they can do for you.
If you’re not able to find somewhere suitable, focus on recyclable products and packaging instead, and stay away from single-use products where possible.
Other terms you should be aware of
Bioplastics
Bioplastics are made from renewable sources like vegetable fats, corn starch, sawdust, and more. By using natural polymers, this alternative to plastic helps reduce reliance on plastic.
However, not all bioplastics are biodegradable or compostable. Some bioplastics are partially bio-based or are petroleum-based.
Oxo-degradable
If you see a product advertising itself as oxo-degradable, avoid it at all costs! These products aren’t made from organic matter or bio-plastics.
Instead, they’re made of “conventional plastic mixed with an additive in order to imitate biodegradation”, as explained by Green Dot Bioplastics. This creates microplastics that are left in the environment for a long time until they naturally biodegrade.
Microplastics
Microplastics are particles of plastic after the initial material has broken up instead of down. These fragments can absorb toxic contaminants, further polluting the environment, and can affect the ecosystem by starving animals of necessary nutrients.
They have also been linked to harmful health effects like cancers and weakened immune systems. True biodegradable and compostable products should never result in microplastics.