I'm always curious about how long things last, so when I heard that biodegradable plastics were made from trees, I was immediately intrigued. But are they more expensive than regular plastic? And how do they break down? This article explores the answers to these questions and more.
Biodegradable plastics are not made from trees. Instead, they're made from oil—which is a non-renewable resource. Oil is essentially a finite resource. It can be used up at any point in time and never restored to its original supply (the same way you could use up all of your money at any point). This means that when we use oil to make plastic, we're depriving future generations of the same resources that we have now. It also means that if we don't start conserving our supplies now and find new sustainable sources for our plastics industry, by 2050 there will be more plastic than fish in our oceans!
Yes. Biodegradable plastics are more expensive than conventional plastics because they require a higher level of processing. Bioplastics can be made from materials like starch, wood fiber and cellulose, but each material has its own properties and production costs.
Biodegradable plastics have been developed in order to address the pollution currently seen in landfills, oceans and rivers around the world. Processing these types of plastics requires more time and effort than conventional plastic because they need to be treated differently during the manufacturing process. As a result, bioplastics generally cost more than their non-biodegradable counterparts.
Do all biodegradable plastics break down in the same amount of time? No! There are many different kinds of degradation rates and pliability (i.e., how easy they are to break down) among bioplastics. While some biodegradable plastics may decompose faster than others, this can also vary based on environmental conditions such as temperature, humidity and light exposure.
PLA stands for polylactic acid, and it’s the most common type of biodegradable plastic. PLA is made from plant-based materials, including cornstarch and sugarcane. It’s used in many disposable food containers as well as other products like packaging for electronics and cosmetics.
PLA is also the main ingredient in corn-based nurdles—those tiny white beads that you see in everything from shoes to shampoo bottles to construction materials. These nurdles are often made from recycled plastics that have been ground down into a fine powder, so they can be melted together into a new product.
But let's get back to those cereal box liners we mentioned earlier... The average American eats around 25 pounds of cereal per year—most of which comes in plastic-lined boxes made with PLA or other types of biodegradable plastics!
Compostable plastics are made from renewable resources, such as cornstarch or sugarcane. Compostable plastics break down into carbon dioxide, water and biomass when they're exposed to certain conditions such as high temperatures for a long period of time.
Composting is the process of breaking down organic matter in a controlled environment. It can be done on the ground or in an enclosed container (like a compost bin), but neither method will create the same results as aerated composting—a process that uses oxygen-rich air to speed up decomposition—and requires specialized equipment. You've likely seen commercial versions of this type at parks and restaurants where food scraps are turned into rich soil amendment for local farmers' fields.
If you're shopping for biodegradable or compostable plastics, you should be able to tell by looking at the packaging. If the plastic product has a number 1 inside of a triangle, this means that it is recyclable and made from 100% renewable resources.
If the packaging has PLA or Bio written on it, it means that there are parts of the plastic that are made from corn or sugarcane rather than petrochemicals. These kinds of plastics aren't always labeled "compostable," but they can still be recycled in your home compost bin if you're feeling ambitious (and have enough room).
Plastic products will also sometimes include text that says something like "recyclable" or "biodegradable," which both indicate whether they can be broken down by microorganisms in landfills and wastewater treatment facilities—which sounds pretty great!
The jury is out on whether or not composting bioplastics is actually harmful to the environment. While there's some evidence that composting can release greenhouse gases, it's debatable as to how significant this impact might be.
For example, in a study published in the Journal of Environmental Quality (vol. 30), researchers found that plastics containing a mixture of polyethylene and polypropylene released greenhouse gases when they were heated (to around 140 degrees Fahrenheit) during composting. However, because these plastics are only partially biodegradable and are often treated with chemicals to make them more durable, they're typically not used by consumers—meaning that they're not going into your backyard compost bin anyway!
In another study published in Waste Management (volume 18), researchers analyzed samples from landfills across Europe and found higher levels of heavy metals than those found in regular municipal solid waste sent to landfills. But again—this was due to non-biodegradable plastics being used for packaging or disposal purposes rather than for products meant for personal use like coffee containers or water bottles!
As you can imagine, it's not a great idea to put biodegradable plastic into the same compost bin as other types of plastics. In this case, "biodegradable" means that it will eventually break down in the environment—but only if it gets there in one piece (and with no other materials mixed in). It doesn't mean that the material itself is compostable in any meaningful way (even though some brands might use this word to describe their products).
The reason why bioplastic isn't compatible with regular plastic has to do with how each type breaks down over time. When you make something out of traditional petroleum-based plastics like polyethylene or polypropylene and throw it away, those chemicals don't easily return to their original chemical composition; instead they float around as tiny particles called microplastics until they either sink or get eaten by wildlife somewhere along our modern waste stream. Bioplastics are different: once they're exposed to air and water for long enough—which could be months or years depending on how thick your plastic bag was when you folded it up—their molecules begin breaking apart so that eventually what remains resembles plant matter rather than synthetic material (hence the term ". . . degrades"). But since there's no known way for microorganisms or worms living inside your backyard compost bins (. . . well . . . maybe) know whether an object has been made from petroleum products versus vegetable oil derivatives; using them together also runs the risk of contaminating other items that would otherwise break down quickly if left alone!
Another consideration is that bioplastics are made from renewable resources, which means they're less likely to pollute the environment. They also have a lower carbon footprint than regular plastic, making them better for the planet in that way.
However, bioplastics do come with their own unique set of environmental impacts:
There are many types of biodegradable plastic: some break down in a few months, others take years to break down. In general, the longer it takes for your product to decompose, the more it will cost you.
Bioplastics are an exciting new development that can help reduce our reliance on petroleum-based plastics. But it’s important to know exactly what biodegradable means before you buy any goods that are labeled as such, so you’re not left with a bunch of useless garbage after they break down!