1) PLA is not biodegradable it is degradable. 2)Enzymes which hydrolyze PLA are not available in the environment except on very rare occasions.

Is PLA really environmentally friendly?

PLA consists of renewable raw materials and is biodegradable in industrial composting plants. ... Overall, it can be said that PLA is somewhat more sustainable than plastic from fossil fuels due to its production from renewable raw materials and the possibility of biodegradation.

Is PLA biodegradable or compostable?

PLA: Conditionally compostable

Because it can be derived from plant material such as corn sugar, potato or sugar cane, it can reduce the demand for fossil fuels used to make conventional plastics. PLA is recyclable, biodegradable and compostable.