Do compostable bags break down into microplastics?
Compostable bags contain no plastic.
But don’t get confused by the term “biodegradable”
—this means mineral fillers were added to plastic to shorten the long carbon chains that make plastic last essentially forever. Biodegradable bags break down into smaller bits, but they are not compostable.
They become microplastics.
On the other hand, compostable bags are made of plant-based materials—not petroleum or natural gas based polymers like plastic
. These bags degrade into plant-based nutrients that can enrich soils.