A new study just came out regarding air quality safety and 3D printing. To my mind, it just reinforced my choice to only use PLA instead of ABS, because of the KNOWN hazards of ABS. PLA may also be hazardous, but:
the primary individual VOC emitted from PLA filaments was lactide … albeit in relatively low quantities (p. F)
We are not aware of any relevant information regarding the inhalation toxicity of lactide, the primary individual VOC emitted from PLA filaments. (p. G)
I spoke about this issue here 2 years ago, and I still feel like a large, well-ventilated room with a PLA printer is unlikely to harm anyone–unless someone sits next to it all day everyday. Then an air filter is a good idea. But I am not a plastics scientist or health expert, so be cautious!
Azimi, P., Zhao, D., Pouzet, C., Crain, N., & Stephens, B. (2016, preprint). Emissions of ultrafine particles and volatile organic compounds from commercially available desktop 3D printers with multiple filaments. Environmental science & technology.