This was an ornament I printed roughly 6 years ago. Being a Christmas ornament it spent most of those 6 years stored in my roof space.
Being in Australia this would have been subject to average temperatures of 30 to 35 degrees c but also peaks across summer approaching 70 degrees c. Also in high humidity.
The PLA crumbles into tiny pieces at the softest touch.
I thought it was interesting that PLA would start to break down in these conditions.
PLA is widely used as a medical plastic and its normal decomposition is into lactic acid.
Even if it is just being atomized down into smaller and smaller particles it’s safer for you than any other common plastic.
The colorants added are the only risk
Not entirely true as there are no industry standards for PLA. Lots of manufacturers add things they don’t put on the label. Especially in the variants like PLA+ and High Speed PLA.