My printer has a transparent enclosure. I heard about ABS emitting particles so I thought I'd try an unscientific test. I killed the light in my work room while the printer was running and shot a green laser through the enclosure. I did not see the beam or any scintillations inside the box at all (unlike the rest of the room). Maybe the particle size is too small to see that way...
Ultra MegaMax Dominator 3D printer: [
drmrehorst.blogspot.com]