The types of fumes that can be generated by a laser engraver are even more varied than the materials they can process. A laser engraver can turn a single material into dozens of chemicals. The particulate generated by lasers is usually in the 1- to 5-micron range, which is harmful as this particle size is the easiest to get stuck in your lungs.
Lasering acrylic generates large quantities of methyl methacrylate, which is an irritant to the skin, eyes, and mucous membrane. The particulate from glass can lead to silicosis, and polyoxymethylene gives off copious formaldehyde, which is an irritant and has been linked to some types of cancer.