study warns that home grade 3d printer poses similar threat as smoking

The emission rates measured during the printing of small plastic figures were similar to cooking on a gas or electric stove, or burning scented candles and even as harmful as cigarette smoke indoors.
The study found that these printers produce a high amount of “ultrafine particles” (UFP), which have the ability to become deposited in the lungs and penetrate the tissue, becoming absorbed right into the blood stream.

from globalnews