Compostable! Biodegradable! But what is it exactly?
“Commercially compostable only. Facilities may not exist in your area.”…hmm…
Can I just throw biodegradable plastics in our backyard compost bin? It says it is biodegradable. Oh wait, there are more writings on the plastic! “Commercially Compostable Only” …“Facility May Not Exist in Your Area” Oh geez. Now what.
First of all, what is the difference between compostable and biodegradable? I thought these were the same…
Compostable plastic means it can break down into non-toxic, natural elements in a commercial compostable setting. Made from plants instead of petrochemicals from fossil fuels.
Unless the product says it’s okay for backyard composting, it can only compost in commercial composting facilities which have higher temperatures and different breakdown conditions. Compostable plastics are usually obtained from starch from corn, potatoes and sugar canes and leave no toxic residue.
On the other hand, Biodegradable plastic, often called bioplastic, means plastic made from renewable resources like plants rather than fossil fuels mixed with other chemicals.
Traditionally biodegradable means having the ability to be disintegrated by bacteria or other living organisms. And it doesn’t necessarily mean it will turn back into soil. So some companies are taking advantage of using the term biodegradable just for marketing purposes.
Two of the most commonly used bioplastics are called PHA (polyhydroxyalkanoate) and PLA (polylactic acid) which is made from natural materials such as corn and sugarcane and that can be broken down by microorganisms only under certain conditions in industrial composting facilities. It takes months to finish the process. In order for the bacteria to break down those plastics, the facility has to break down the tough molecules which we cannot do at home or in a landfill. It sounds like a good idea to send the biodegradable plastics to those facilities, but unfortunately since they don’t have enough bioplastics to operate at this moment, only a few of them exist in the US and they don’t operate much.
Now you know that compostable plastics are biodegradable but biodegradable plastics are not necessarily compostable. You can tell how people get confused by these two words, right?
In my opinion, if you need to use those compostable/biodegradable plastics, I would choose the ones with the “home compostable” label, which can compost at lower temperature.
Though, if you mistakenly throw these plastics into your regular recycling bin, it could contaminate and disrupt the recycling stream. So make sure to take the compostable plastic or bioplastics to the correct facilities or (unfortunately) trash bin.
If sugars from corn and sugarcane become the future of plastic, we still have to consider how agriculture will respond to these productions. Remember, plastics are just one part of our environmental problem.
Obviously the best is not to use plastics! You can start with saying no to the plastics when you go to the supermarket or ordering takeout food. Use wax paper instead of ziplock bags or plastic wrap. If possible, bring your own utensils everywhere you go (ask parents to keep them in their car). When we go to an ice cream shop, I often see these “biodegradable spoons” and this confuses me what to do with it after I use it so I use my own!