Polypropylene (PP) is a thermoplastic polymer (a type of plastic) that has a wide variety of applications. It’s a very durable plastic that is resistant to fatigue, which is why it’s used for things such as flip-top bottles, piping systems and kettles. It’s also used in sanitary products, woven bags and to seal tea bags No, polypropylene is not biodegradable.
Unfortunately, the term ‘biodegradable’ is often defined vaguely. The Cambridge Dictionary defines ‘biodegradable’ as meaning something that is “able to decay naturally and in a way that is not harmful”.
Other definitions often say that something is biodegradable if it can be broken down by microorganisms relatively rapidly (usually within a year). Polypropylene (PP) takes about 20-30 years to degrade, and will release toxins in the process, so it can’t be described as biodegradable. Since all plastics contain harmful toxins that will leach into the soil when broken down, it could be argued that no plastic is really biodegradable.
Some plastics are labelled as biodegradable since they break down more quickly, but this doesn’t mean they are safe for the environment.
Also, biodegradable plastics aren’t always as biodegradable as they’re made out to be. Sometimes these plastics will only degrade quickly in temperatures above 50°C, so they won’t break down in the earth or the ocean.