As PLA is the type of filament that melts at a lower temperature, around 190-220°C, it's less prone to warping and is less resistant to heat. Although breathing in the fumes of any plastic can't be good for anyone whatsoever, as compared to the infamous ABS, PLA comes out on top in terms of emission of toxic fumes.

Is PLA toxic to breathe?

PLA Filament Fumes

It is made from entirely natural substances such as maize and sugarcane. This is why it smells so nice and sweet when heated up! When it is heated, PLA gives off a non-toxic chemical called Lactide. A lot of people say, if you're using PLA, you shouldn't worry about breathing in the fumes.

Is PLA plastic toxic?

In fact, Polylactic Acid (PLA) is biodegradable. It is often used in food handling and medical implants that biodegrade within the body over time. Like most plastics, it has the potential to be toxic if inhaled and/or absorbed into the skin or eyes as a vapor or liquid (i.e. during manufacturing processes).