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.
My boss printed me three LEGO bricks when he got his 3D printer (everyone here knows I am an AFOL = Adult Fan Of Lego). I have no idea what kind of printer that was, but the bricks were very detailed. Now they have totally warped out of shape. I kept them on my desk in the electronics lab, so heat or sunlight are no major issues here.
Maybe fumes from solvents in the room?
No solvents, thank goodness. It’s a lab, but it’s an electronics lab. And no, anything with soldering or cleaning boards is done far elsewhere.