While everyone knows the unpleasant odor from ABS cannot possibly be healthy to breathe in, most of us generally do not really care. However, not only ABS, but also PLA, may release toxic fumes known as VOCs (Volatile Organic Carbon). Not all VOCs are actually toxic, but some may be, especially for younger users. Before this becomes a serious health issue, a new study conducted by 3Dsafety.org, in collaboration with Italian 3D printer manufacturer WASP, has analysed the exact quantities of toxic VOCs – as well as potentially dangerous nanoparticles – released during filament extrusion, in order to assess the potential health risks.
The new study, presented by Dr. Fabrizio Merlo and Dr. Eng. Stefano Mazzoni, starts off from other previous research conducted in the early 90’s, which demonstrated that during the fusion and processing of plastic materials, several toxic particles are released as gases, including ammonia, cyanidric acid, phenol, and benzene, among others.
The lab tests showed that ABS is significantly more toxic than PLA, but that the corn-based polymer is not exempt form dangerous emissions, especially if extruded at temperatures higher than 200°C. Furthermore (as may be expected), the same material spools, when acquired from different resellers, release very different quantities of VOCs, even if used in the same 3D printer and under the same parameters of speed and temperature.
A second critical aspect is that relating to the emission of nanoparticles, that is, particles with a diameter smaller than .1 micron, which can be absorbed directly by the pulmonary alveolus and the epidermis. In this case, the emissions, when using ABS, vary from 3 to 30 times those that occur when using PLA filament. The test also demonstrated that the time necessary for the nanoparticle concentration in the air to go back to standard levels was between 10 and 30 minutes after the extrusion processes stopped. Through a photo-ionization technology, the study (which has been published on 3Dsafety.org and will progressively be updated with further information) was also conducted on nylon, polystyrene, PET and other materials.
Among the effects that the absorption of toxic VOC’s and nanoparticles can cause to humans, the most common are pulmonary pathologies, such as bronchitis, tracheitis, asthma. In some cases, these substances can also cause certain types of cancers, so this is not something to be taken lightly. The solution, however, is not too complicated. 3Dsafety.org, in collaboration with WASP, is working to increase awareness as to the potential risks of toxic emissions from filament, while several practical tips can be implemented right away.
For example, working in well ventilated rooms: the ideal solution would be using an air ventilation system capable of moving three times the room’s volume of air in one hour. This means that a room measuring 100 cubic meters should have a system capable of displacing 300 cubic meters of air in one hour. When using closed-chamber 3D printers, it may be possible in the near future to implement an active carbon filtration device, and the team is actively working toward development of a device specifically tailored for 3D printers, which can be regulated according to the type of filament material used.
Certainly this does not mean we should all just stop using 3D printers. However, dealing with the potential health risks of 3D printing materials early is the best way to make sure this technology evolves in a way that we can maximise its benefits and limit any risks involved.