Biodegradation and composting are linked but they are not the same. Every compostable material is biodegradable but not every biodegradable material is compostable.
I know it sounds complicated so let me explain.
The term ‘biodegradable’ refers to the ability of a material to be decomposed by naturally occurring microorganisms into CO2, water, and biomass. Whether this process takes 3 months or 5000 years, or if it takes place in the soil or an industrial composting facility is, however, not specified. This means that, technically, most products can be labeled as biodegradable, because most things will break down at some point in their life. In addition, there is nothing specified regarding the residue obtained after a biodegradation process, which could in theory be harmful to the environment. When a material is compostable it also biodegrades, but in a controlled environment and conditions (e.g. temperature, humidity, aeration) and within a specified period (e.g. 6-12 weeks).
The end product has beneficial use as fertilizer and in improving soil health. The term ‘biodegradation’ is not well defined, but any statement about composting needs to be accompanied by a third-party certification using ISO standards (e.g. EN 13432 or EN 14995)
It is important to understand that if a material is not composted in the right environment or conditions, a complete breakdown might not occur, or at least not within the specified time frame. A material that is certified as ‘compostable’ in an industrial composter, will not (automatically) be compostable in soil, water, or in your home compost bin. This also means you do not have to worry about your compostable shoes degrading while you are wearing them.
At Stahl, we would like to understand the environmental impact of our products, and their ability to biodegrade and compost will be a factor in the calculation. In this article, we have just touched the surface of compostable materials and surfaces but we are committed to the transition to a circular economy: our products will play a key role in that endeavor.