UV-cured resin 3D printing is a popular choice among hobbyists and makers. A resin printer uses UV light to cure resin, layer by layer. Each layer in the printing process works to form a full 3D print.
But is the 3D printer resin toxic?
The liquid resin used in resin 3D printing is toxic and can cause an allergic reaction if it comes in contact with your skin or eyes.
Read on to learn more about why UV resin is toxic and safety tips you can implement to safely print using resin.
Is 3D Printer Resin Toxic?
Uncured 3D printer resin is toxic and requires safety precautions while 3D printing.
In its liquid form, the uncured resin contains irritants and pollutants which are harmful to humans and the environment.
Uncured liquid resin can cause adverse side effects when it comes into contact with the skin or eyes.
3D printing resins are not food safe.
If you accidentally ingest UV resin, you should immediately call poison control or a medical professional.
Liquid resin gives off fumes or vapors containing volatile organic compounds (VOCs) that can harm humans when inhaled. The VOCs in resin fumes can cause irritation in the throat and lungs and cause dizziness and headaches.
3D printing resin can cause:
- Skin irritation
- Irritation to the respiratory system
- Harmful to the eyes
- Poisonous if ingested
- Toxic fumes
- Harmful to the environment
3D printing resin is considered a “sensitizer,” meaning people who are more frequently exposed to it are more likely to develop an adverse reaction. In other words, the more times you come in contact with UV resin, the more likely you’ll experience bad side effects.
Uncured resin can cause skin irritation when it comes in contact with bare skin. The resulting irritation can cause a rash called dermatitis.
Prolonged skin contact can create more severe reactions, including allergic reactions or burning sensations.
You can wear protective gloves to prevent skin contact. It’s essential to wear the proper PPE, as frequent exposure can increase the chance of adverse reactions.
Several ingredients in 3D printing resins are harmful to the eyes. In the worst cases, if resin makes contact with the eyes and cures in the sunlight leading to loss of eyesight.
Poisonous if Ingested
Resin should never be ingested, whether cured or uncured.
Even in its cured state, UV resin is not food safe and should not be used to create items that come in contact with food.
If 3D printer resin is accidentally swallowed or ingested, seek urgent assistance from poison control or a medical professional.
Liquid resin gives off vapors of fumes that contain volatile organic compounds (VOCs), which may be harmful if inhaled. The toxic fumes can cause irritation to the throat and lungs, dizziness, and headaches.
Harmful to the Environment
3D printing resins are considered hazardous waste as they harm the environment. The harmful chemicals should never be poured down the drain, into bodies of water, or outdoors.
Photopolymer resins should be safely bottled and disposed of through proper toxic waste disposal companies.
Cured 3D resin is less environmentally harmful and can be disposed of in regular garbage. Plant-based, or bio-resins, might be safer for the environment, even in their uncured liquid state.
Safety Tips for Using UV Resin
Although UV resin is harmful to people, they are safe to work with when you take the appropriate safety precautions.
You can protect yourself by wearing the proper PPE, like gloves and safety glasses, and working in a clean, well-ventilated area.
Prepare the Work Area
Liquid resin fumes are toxic, so working in a well-ventilated area is essential.
The best solution is to work in an area with an overhead ventilation hood to ensure that harmful fumes are removed. You can create a makeshift ventilation hood at home to disperse toxic fumes from your work area.
If it’s not possible to set up a ventilation hood, you should position your work area close to an open window.
Your work table is a non-porous surface, such as a glass table. It’s best to cover the work surface with a plastic or silicone sheet to minimize spilling, making for easy cleaning.
Avoid printing on a porous surface, such as wood or fibreboard. UV resin can seep into the wood, which can be harmful in the future.
Read the SDS
All manufacturers of 3D printing resin must provide a safety data sheet (SDS). The SDS provides information on the resin’s ingredients, toxicity levels, and appropriate safety measures to take when working with the material.
The information on the bottle also provides information on properly storing the resin and gives you the expiration date.
When handling uncured resin, it’s essential to wear nitrile gloves. Nitrile gloves prevent toxic liquid resins from coming in contact with bare skin.
Even if you’re not directly touching the resin with your hands (for example, while pouring resin into the vat), it’s a good practice to wear gloves, as spilling or splashing can occur.
Wear Safety Goggles
Safety goggles or safety glasses should be used when handling toxic resin. The ingredients in the resin can be harmful to the eyes and can result in loss of eyesight if resin cures inside your eye.
Wear a Respirator
You can never be too safe, even when working in a well-ventilated area. Wearing a respirator prevents you from inhaling toxic fumes from uncured resin and avoids irritating your respiratory system.
For long exposures with UV resins, it’s best to wear a half-mask respirator with an organic vapor filter.
A standard disposable face mask or N-95 mask will work for short exposures. As the long-term effects of resin fumes are not yet known, we like to err on the side of caution and wear our respirator when working with 3D printing resin.
Cure Uncured Resin
Fully cured resin is far less toxic when cured. When cleaning spilled resin, it’s often a good idea to cure it with a UV light before wiping it up.
Hardened resin is also easier to dispose of because it poses less of a risk to people and the environment. If you don’t have a portable UV light, you can place the liquid resin in the sun to cure it.
Paper towels used to clean liquid resin should also be cured before disposal.
How to Clean Spilled Resin
If you spill resin on the ground or your workspace, you can clean it by using soap and water, then wipe it down with isopropyl alcohol (IPA).
You want to first use soap and water because it protects the surface from stripping. IPA is essentially a paint thinner. If you clean up the spill with IPA before cleaning with soap and water, you may strip the surface of the object you’re trying to clean.
How to Dispose of Uncured Resin
You should never dispose of liquid resin. We now know that liquid resin is highly toxic and can cause harm to humans, animals, and the environment.
It’s vital to cure resin before disposal.
You don’t need to use a 3D printer to cure the unwanted resin. A portable UV light can cure the resin in minutes. But if you don’t have a UV light, you can put your unwanted resin or failed prints into a plastic container and leave it in the sun for a few hours.
The UV radiation from the sun cures resin and makes it safe for disposal.
Fully cured resin can be disposed of with your regular household garbage.
Plant-based resins, or bio-based resins, are made from natural sources. Plant-based resins are less harmful to people and the environment than traditional UV-cured resins.
Surprisingly, plant-based resins have comparable performance to standard resins.
Here are four plant-based resins to try with your resin printers:
Is UV Resin Toxic After Curing?
Cured UV resin is not toxic. Once the liquid resins are cured, they are safe to touch with your bare hands.
Is it Safe to Print Resin Indoors?
It is safe to 3D print resin indoors in a well-ventilated area with the proper PPE. If you’re printing indoors, using a low-odor and low-VOC resin such as a bio-resin is best.
Should You Wear a Mask While Using UV-Cured Resin?
You should wear a mask while working with UV resins like those used in 3D printing. A mask with an organic vapor cartridge can prevent you from breathing in toxic fumes.
Even with a mask, it’s best to work in a well-ventilated area to prevent toxic fumes from migrating throughout your home.