Compostable plastics may look, feel, and perform just like traditional plastic, but they are eco-friendly, plant-based products that can usually go straight into your green bin and get picked up curbside with your kitchen waste! Instead of getting recycled or ending up in a landfill, compostable plastic products can be broken down into usable compost.
There are many innovative, compostable plastics available on the market today, and sometimes it can feel complicated to find and use the right products for your household needs and composting habits. From “bio-based” to “biodegradable,” here’s what every Canadian should know about compostable plastics—and how to make smart, environmentally sound buying decisions.
Not all “biodegradable” and “bio-based” plastics are compostable
When you’re looking to make eco-friendly purchasing choices, it’s important to keep in mind that not all bioplastics are actually biodegradable, and not all biodegradable plastic is compostable.
Biodegradable plastics can be broken down by microorganisms like bacteria and fungi into biomass, water, and carbon dioxide or methane. But for some products, this process can take a long time and require specific environmental conditions.
The U.S. Department of Agriculture defines bio-based products as “composed in whole or in significant part of biological products, forestry materials, or renewable domestic agricultural materials” instead of natural gas or oil. For example, polylactic acid (PLA) is a biopolymer plastic made from plants like corn, sugarcane, and potato. Some bio-based plastics can be recycled.
According to the United States Environmental Protection Agency, compostable plastic should be biodegradable, but it also must be “able to be broken down by biological treatment at a commercial or industrial composting facility” in a reasonable amount of time and without leaving any “toxic residue that would adversely impact the ability of the finished compost to support plant growth.”
Many compostable plastics are designed to work with industrial composting systems
Unless they are specifically labelled for use with home composting systems, the majority of compostable plastics are designed to work with municipal and commercial composting programs, so they won’t simply break down in your backyard pile or outdoor composter.
If you have access to a curbside organics program, you’ll want to check the specific requirements in your area and confirm that compostable plastic products are accepted. Additionally, look for items that are designed or labelled in a way that can help them stand out from non-compostable plastics. This helps the waste-management company identify compostable items, and can prevent compostable items from accidentally ending up in standard recycling streams. Compostable plastics cannot be recycled, and should not be mixed in with recyclable plastics.
Look for certified products
In Canada, organizations like the Bureau de normalisation du Québec (BNQ), which is accredited by the Standards Council of Canada, and the Biodegradable Products Institute (BPI) offer science-based certification services that can help you identify effective compostable plastics. As part of the process, they perform lab testing to confirm the product’s chemical composition and the time it would take to biodegrade in specific settings.