Is PLA truly biodegradable?

Fact: PLA is biodegradable
Fact: Nature cannot decompose pla without human help

You will probably say that these 2 facts are very contradictory, but they are equally true.

So is PLA really biodegradable or is it just marketing?

"PLA (Polylactic acid) is made from natural corn starch, biodegradable and BIO! "

In this manner PLA sounds (and smells) so good that we can slowly start 3D printing gnocchi at home and eat them.
This is how PLA is sold to us, this is how we will sell it to you because it is in fact true, PLA will be biodegradable at some point.

However, marketing will not specify when and how the PLA will be this perfect.
Let's start with a very important definition: What does "Biodegradable" mean?

– That I throw it into nature and in 2 months it's gone
– A substance or object capable of being decomposed by bacteria or living organisms without polluting the environment.

Reality:

PLA will still be just plastic, and if we don't treat it responsibly, nature won't cope, despite all its amazing BIO properties. PLA will take thousands of years to decompose in our normal climate, and our print will be just another piece of plastic in nature. PLA is not as weak material as it seems to be.

So how to decompose PLA? (Recipe)

PLA = Industrial composter + 60°C constant temperature + 2/3 organic substrate cocktail + 80% humidity + lots of oxygen + minimum 5 days.

These conditions may be available to 0.1% of us, and thus in the other 99.9% of cases, a PLA printout can be considered an ordinary piece of plastic that will lie next to other plastics for the same amount of time.

Which PLA is the least harmful?

The least modified PLA is transparent (uncolored), as this is its initial form after production. Transparent can be considered as "Real unmodified raw PLA". By the way, it is also the best printable. Black, blue, red, and all colored plates are already modified by adding color pigments, manufacturers have different pigments, so it is not possible to determine an exact rule about which color is the most harmful. In general, black filaments are the most modified (it is necessary to put more pigment into them than others) and therefore filaments of the same material but of a different color may be printed slightly differently.

However, Pla will still have an advantage over other plastics, namely that when it decomposes after those x years, it will not leave behind anything harmful (according to the definition: it decomposes without polluting the environment)

What do we propose? – Conclusion

The most ideal general solution that currently exists for plastics is to preserve them in their final form and reuse them.

We ask you to work with our filaments as responsibly as possible, and in any case, whether it is PLA, ABS, PET-G, never throw away the remnants after printing in the yellow container. This is because the surpluses after printing are not marked and only cause problems in the sorting lines. Unfortunately.

The least modified (and best printable) is transparent PLA. It is still better to use PLA than for example ABS, as when PLA finally decomposes, it leaves no traces behind.