Compostable Versus Biodegradable: What’s The Difference?

In this era of trying to tackle climate change, we’ve been introduced to new technologies and terminologies. However, these terms sometimes get jumbled up. Take, for example, compostable and biodegradable; two terms that many think are interchangeable. Let’s take a moment to explore what these terms actually mean.

Compostable

Compostable indicates that a product can decompose into natural constituents in a compost environment. Compostables are materials that break down in the composting process through biological processes to create inorganic compounds, water, CO2, and biomass at a rate equivalent to other compostable materials while leaving no trace behind.

Biodegradable

Biodegradable items can be broken down under any conditions, not just in a compost. Bacteria, fungi, and other biological activities can contribute to the process. Unlike compostable items, they don’t necessarily break down into their basic components. Depending on the material, at least.

When you look at the definitions of both terms, it’s easy to see why they’re used interchangeably, yet there is a distinction. If it’s compostable it’s biodegradable, but biodegradable isn’t always compostable.

Biodegradable plastic

If plastic is biodegradable, it essentially breaks down into microplastics faster than “regular” plastic. Depending on what the plastic is made of, this can be extremely dangerous. Petroleum-based plastics just break down into microplastics faster and continue to pollute the environment. Bioplastics, such as those made of corn, will still break into microplastics, but they will not leave toxic residue behind. Meanwhile, composts are nutrient-rich environments that help promote future plant growth.

In short, compostable products, when disposed of properly, are harmless whereas biodegradable products have mixed results.