Is 3D printing dangerous?

There are a huge number of objective benefits associated with 3D printers that make users around the world happy to use them in their schools, libraries, and homes. As barriers to access and use of 3D printers have exponentially decreased over the past decade, 3D printing has become much more mainstream. With this increasing popularity, there has been a spike in interest regarding potential health and safety concerns associated with the use of 3D printers—especially as more and more of us have one or more printers in our homes.

There are two major types of additive manufacturing processes: fused-deposition modeling (FDM) and stereolithography (SLA). FDM printers use heat to melt a solid thermoplastic filament, which then cools and hardens into the desired model. SLA printers use UV light to cure a resin mixture of short-chain carbon molecules into a solid plastic model. Researchers have found that both processes frequently release carcinogenic and irritant byproducts, which can cause short-term discomfort and have potential long-term health effects if safety measures are not implemented.

We don’t want to scare you—we believe it is important for hobbyists to be aware of all the risks associated with 3D printing so they can make healthy, informed decisions and keep themselves safe while printing. This guide covers what we know about potential toxicity and other dangers associated with 3D printing and provides useful tips for keeping your workspace safe and reducing the risk of exposure to harmful byproducts during and after the 3D printing process.

Potential dangers associated with 3D printing

The major risks associated with 3D printing are the release of carcinogenic chemicals, release of nanoparticles that can irritate the skin and lungs, and emission of volatile organic compounds (VOCs), which have been reported to cause irritation, headaches, and organ and nervous system damage following long-term exposure.

While this article focuses on the chemical and particulate irritant risks of 3D printing and their impacts on users, it is also important to remember that more than just humans are affected by these emissions—pets, wildlife, and the ecosystem can all be damaged by reckless use of 3D printers in both residential and commercial workspaces.  

Are some 3D printing filaments more harmful than others?

Each type of thermoplastic used in FDM printing has different characteristics. Manufacturers include different base plastics and additives to promote strength, flexibility, color, or conductivity in the final material, which can lead to various chemicals being off-gassed or nanoparticles being released into the surrounding environment. Several research projects, including two headed by the US Environmental Protection Agency, have evaluated the emissions associated with different types of 3D printing filament and explored their potential effects on human and environmental health. We cover the key findings associated with the most common types of 3D printing filament below.

ABS

Acrylonitrile butadiene styrene (ABS) filament is a highly durable thermoplastic that is frequently used by both commercial 3D printing companies and hobbyists for its temperature resistance and strength as well as its reliability for rapid prototyping.  

Acrylonitrile alone is a toxic chemical known to have carcinogenic properties and has been subjected to stringent workplace safety standards in industrial manufacturing facilities working with this material. Styrene is also known to be toxic, though it is less harmful than acrylonitrile. In ABS filament form, these toxic compounds are more stable and can be handled safely. However, the heating and cooling process that occurs during printing releases toxic fumes.

Some ABS manufacturers include bisphenol A (BPA), which has raised significant concern over recent decades due to its abundance in all types of plastics. BPA is considered a probable carcinogen with known toxic and irritant effects in human and animal respiratory and digestive systems.

Due to the off-gassing that occurs when printing with ABS, it is widely considered among the highest-risk materials to work with and requires specific safety considerations.

PLA

Polylactic acid (PLA) filament is by far the most widely used 3D printing material owing to its beginner-friendliness, reliability, and good finish. The base material of PLA is a naturally derived starch, often corn glucose, that is subjected to an enzymatic reaction and subsequent fermentation to produce lactic acid polymers, which can be bound into a hardened plastic under certain conditions.

While many users and manufacturers celebrate the ecofriendliness of PLA filament due to its naturally derived base, researchers have found that some companies include specific property-enhancing  additives, such as materials that improve the filament’s flexibility or help it retain color after heating, which can promote the release of harmful substances throughout the printing process.

Whether or not your PLA filament has problematic colorants or additives, it still releases ultrafine particles after heating, which can act as skin and respiratory irritants, particularly in pets and children. The accumulation of these particles in the body can lead to increasingly severe toxicity responses, although this is primarily a concern in industrial facilities using this material.

PETG

Polyethylene terephthalate glycol (PETG) filament is an increasingly popular FDM filament option owing to its high durability, ease of use, and food-safe properties. Polyethylene is the most widely used plastic in the world and is known to be highly stable under a wide variety of conditions.

Because polyethylene and terephthalate, a salt, serve as the base materials for PETG filament, it does not degrade or off-gas significantly under normal printing conditions. As a result, it is considered among the safest 3D printing materials to use, particularly for residential/hobby applications.

The heating of any type of plastic can release some irritant particles, so basic safety protocols should still be followed when using PETG.  

TPU

Thermoplastic polyurethane (TPU) filament is a popular option for highly flexible 3D prints that can be used to create rubber-like prints that retain structural integrity and shock-resistance. Like PETG, the base materials used to create TPU filament are highly stable under room temperature and heated conditions. As of the time of writing, researchers have not found hazardous fumes associated with TPU printing that make it dangerous to print with in enclosed areas.

Is SLA resin toxic?

Generally, SLA resins are considered more toxic than their FDM filament counterparts owing to the ease with which the chemicals can absorb into the skin. While there have been few studies on the potential toxicity and carcinogenicity of resin fumes, it is known that some chemicals that are released during the resin printing process can cause headaches and respiratory irritation.

Resins also release VOCs during printing, which pose a risk to both humans in the workspace and to pets. Like filament, resins also release ultrafine particles that can accumulate in the surrounding environment during and immediately after printing.

Safety measures for 3D printing

As noted above, the most common risks to human health associated with 3D printing include hazardous fumes and nanoparticle emissions that can have short-term irritant impacts and pose long-term risks if repeated exposure occurs.

Choose the right workspace

If possible, maintain a designated workspace for your 3D printer(s), preferably a garage or office that can be well-ventilated. Avoid keeping your 3D printer(s) in a family room, kitchen, or bedroom. Regardless of how your hobby space is setup, maintaining good ventilation is crucial. Keep your workspace near a window and use fans to circulate the air away from inhabited spaces in your home. We know that air and temperature fluctuations can mess with prints, which makes some hobbyists hesitant to keep windows open during the printing process. Buying or building a 3D printing enclosure will keep cool air from messing with the hardening/curing process while allowing you to maintain good airflow throughout the work space.

Keep your distance

We recommend staying out of the immediate vicinity of your 3D printer for the duration of the print. While one should never leave any heated appliance on completely unattended, it is important to reduce the risk of exposure to nanoparticles and fumes that can be released.

Setting up a remote monitoring system is easy and can allow you to leave the immediate workspace while keeping an eye on your print and your machine. If you live in a very small space and cannot reasonably leave the area, such as a desktop printing setup in a studio apartment, only use filaments like PETG and TPU, which are much safer than PLA and ABS.

Use an air filtration system

While passive and mechanical ventilation (fancy terms for keeping a window open and using a fan) are important for working with 3D printers of any type, hobbyists who work with riskier materials like ABS and PLA or who use SLA printers should invest in a ventilation system that suits their workspace.

Here are some examples:

• If you have a garage or workshop, outfit a window or a duct with a ventilation adapter that draws out air and circulates fresh air in throughout the printing process.
• If you have a desktop workspace in an office or spare room, use an enclosure with a designated fan and air filter, which carries out the process outlined above on a much smaller scale.

Use PPE

Regardless of the type of 3D printer you use, personal protective equipment (PPE) is a must. Make sure you have gloves, a filtered mask, and washing materials available at all times to reduce the risk of skin exposure, inhalation, and spills.

The verdict

There is no doubt that there are some major health and environmental concerns associated with 3D printing, particularly at scale. Even for the at-home hobbyist, we know that there are undeniable hazards. Knowledge is power—by understanding the risks associated with your materials of choice, you can keep yourself, your pets, and your environment safe and limit exposure with any harmful vapors or irritants.