If something sounds too good to be true, it often is. Such is the case with so-called compostable plastics.
Berkeley City Council members met last week to discuss sustainability initiatives about plastic in grocery stores and other commodity markets. Part of this conversation included the usage of compostable bags in produce sections of grocery stores, bookstores and clothing stores. While we commend this commitment to sustainability and appreciate the extension of the conversation beyond grocery stores, one distinction must be made: Compostable plastics are not a viable, long-term solution to our plastic crisis.
While biodegradable plastics are engineered to degrade in soil or water, compostable plastics specifically refer to materials that degrade into the soil. All compostable plastics are biodegradable, but not all biodegradable plastics are compostable. However, both biodegradable and compostable plastics are derived from starches such as corn, tapioca or soy. Growing plant products to produce bioplastic can be extremely resource intensive, drawing on our finite supply of water and fertile soil.
Contrary to popular belief, these plastics don’t always disappear as they are advertised to. In a study on bioplastics, several samples were still intact even after months or years spent in marine and garden soil environments.
And when bioplastics do successfully degrade, this prompts more questions than answers. These bioplastics might simply degrade into harmful microplastics that accumulate up the food chain.
But the vast majority of bioplastics end up in a landfill. Most bioplastics are marked with the #7 “other” plastic classification, which simply means that the plastics don’t fall under a normal recycling classification and may not be recyclable. And while they are certified by the Biodegradable Products Institute, a third-party bioplastic testing agency, the testing conditions — which can involve months in an industrial-grade processor at 122 degrees Fahrenheit — are nearly unattainable outside of the controlled environment.
We’re stuck in a cycle of thoughtless consumption, whether or not the plastic comes from petroleum or corn.
Breaking this cycle requires that we let go of our addiction to convenience. Single-use plastics — even if they are labeled as “compostable” or “biodegradable” — cannot coexist with sustainability. Instead of falling prey to the tactics of greenwashing, Berkeley must make bold steps to move away from single-use plastics altogether. This will require a bold solution that prioritizes equitable access to reusable containers and bulk commodities.
The solution to the plastic crisis will require innovation and imaginative thought — but it will not be found in our comfort zone.