Apr 05, 2021
Compostable VS Biodegradable? What is the Difference?

What is Compost?
Compost is organic material that can be used to help grow plants and keep soil healthy. In the process of breaking down your organic wastes, microorganisms produce a rich earthy substance called humus that is the key component in good compost and in healthy soils. At the end of the day your food scraps, yard wastes, and compostable materials can return to the soil where they are useful, important parts of life-giving soil.
What is Compostable Product?
Compostable Product is a product that is “capable of undergoing biological decomposition in a compost site as part of an available program, such that the product is not visually distinguishable and breaks down to carbon dioxide, water, inorganic compounds, and biomass, at a rate consistent with known compostable materials and leaves no toxic residue.” American Society for Testing & Materials (ASTM).
In order for a product to be called compostable, three (3) criteria must be met:
1. Biodegrade - break down into carbon dioxide, water and biomass at the same rate as cellulose (paper).
2. Disintegrate - the material is indistinguishable in the compost, that it is not visible and needs to be screened out.
3. No Eco-toxicity - the biodegradation does not produce any toxic material and the compost can support plant growth.
What is Biodegradable Product?
Biodegradable product is a product that can be broken down by the microbes in the environment and use as a food source under the right conditions.
What is the Difference Between Compostable & Biodegradable?
(1) Compostable set specific time limits for biodegradation while Biodegradable not.
For biofilms/bio bags or paperboard products, the time limit is usually within 90 days. For bioplastic cutlery such as CPLA cutlery with much bigger thickness, the time limit to biodegrade is usually within 180 days.
Biodegradable only means that a product can degrade, but does not provide any info as to how long will it take to fully degrade. You may call regular plastic items biodegradable, but they may take up to 100 years to degrade!
(2) Biodegradable doesn't provide any info regarding if the end products are toxic-free.
For a product to be called compostable, its end products need to be toxic-free. A regular plastic cup, can also call a biodegradable product, may break into numerous microplastics after degradation. Its end products are not toxic-free.