Biodegradable vs Compostable…What’s the Difference?

styrofoam cup labeled biodegradable

A Styrofoam cup, labeled “shown to biodegrade 84.3% after 1154 days*”

Trying to make the right environmental choice can be confusing. Some products tout themselves as green – but what’s really beneficial and what’s just marketing? Terms like compostable and biodegradable can be hard to navigate, because they’re often misused and they do not mean the same thing. Lately we’ve seen some confusing examples, like a Styrofoam cup that’s labeled as biodegradable, and compostable K-cup coffee pods being tested for use. When it comes to packaging and food service products like bags or cups, do you know what these terms mean and how to dispose of them properly?

Biodegradable

‘Biodegradable’ simply means that a product will break down into smaller and smaller pieces until microorganisms can consume it, in the natural environment. Because the term ‘biodegradable’ has no standard legal definition, it’s been used loosely by some manufacturers and can confuse consumers who are trying to be green. If something will biodegrade, it means it will break down over some period of time – but that time is undefined and not held to a specific standard.

Products labeled as ‘biodegradable’ should be disposed in your garbage, since they do not meet composting qualifications. Even in the landfill, biodegradable items are unlikely to break down much – we’re talking hundreds of years – due to the lack of microorganisms and oxygen necessary for decomposition. Biodegradable sounds like a marker of sustainability, but in reality these products must go to the landfill.

Compostable

Products labeled as ‘compostable’ break down, and do so in a specific amount of time and under certain conditions. There are defined standards for something to be considered compostable (ASTM D64000).

Can you tell which cups are compostable and which are trash? All are labeled with "eco" graphics. (Left two are compost, right is trash.)

Can you tell which cups are compostable and which are trash? All are labeled with “eco” graphics. (Left two are compost, right is trash.)

Products labeled as ‘compostable’ should be placed in your food and yard waste cart, so they can enter an industrial composting facility and fully break down. The compost produced by these facilities is a valuable soil amendment. It’s important that only compostable materials go into the composting facility – other materials will not break down and will contaminate the final product. No one wants a chunk of plastic fork in the compost they add to their vegetable garden!

Manufacturers want to be hip and market their products as environmentally sound, so it’s important to look past the greenwashing! The most environmentally friendly option is to use durable reusable products, but if you’re going to use disposables, clearly marked compostable products are the way to go.