3D printing is a fun and creative way to make various interesting objects. However, you need to exercise caution if you print a receptacle from which you intend to eat or drink. You’re probably aware that resin filaments are toxic, but you might still wonder if it’s safe to eat from a plant-based resin item.
Plant-based resin isn’t food-safe. Like most 3D resins, plant-based resin requires you to wear protective gear even when handling it. Most plant-based resin is part plant matter and part chemicals. If not cured correctly, it can leach chemicals and house bacterial growth.
If you want to use a plant-based 3D printed object for eating, you need to coat your work in a food-grade epoxy. However, the plant-based resin isn’t food-safe on its own, and you need to take many precautions. If you want to learn more about why plant-based resin filament isn’t a great option as a food or drink vessel, please read on.
Is It Safe To Eat or Drink From Plant-Based Resin Filaments?
It’s not safe to eat or drink from plant-based resin filaments, even if the base ingredients may be non-toxic. Other materials can mix with the resin during printing, making it unsafe for consumption. Also, the resin makes contact with various machine parts, and the article may be contaminated.
You can add food-grade coatings to the print, but that doesn’t guarantee food safety. Bacteria can still gather on the object, and your print will warp if you use hot water to clean it. Plus, the food-grade coating can break down over time, leaving the resin exposed.
It’s riskier when the food touches the 3D print for longer. Limiting food contact time can help reduce the risk, but it won’t eliminate it. After proper curing, a food-grade epoxy coating turns into plastic, making your project safer to eat off. However, you’ll still need to limit the time food makes contact with the item.
Overall, you don’t want to eat off any resin print, including plant-based ones. Although you can take additional steps to make it safer, it’s still not guaranteed to be completely food-safe. There are several ways that minor errors in executing the print, such as curing time, can make your 3D print potentially dangerous to your health.
Why Plant-Based Resin Isn’t Safe for Eating
Let’s take a look at Anycubic plant-based resin. It’s a popular brand that manufactures plant-based resin filament. However, it’s still not food-safe. Nearly half of the resin is soybean oil, but the other portion consists of toxic chemicals to the body. You can expect the filament versions to be the same.
Elegoo Resin is another popular plant-based resin that contains a mix of soybean oil and chemicals that you wouldn’t want to leach into your food. These companies recommend that you wear gloves and avoid touching the resin directly when using these products. Proper ventilation is also essential.
In short, plant-based filament still isn’t food-safe. It makes contact with the Stereolithography apparatus (SLA), which isn’t food-safe. Plus, most 3D plant-based resin formulas still contain toxic chemicals.
Bacterial Growth and Build Up
Clinical studies have shown that microorganisms may attach themselves to inanimate surfaces as biofilms in a process called ‘biofouling.’ The 3D industry in medical fields shows the impact of biofouling on 3D printed materials. This problem has implications for the safety of using 3D items as receptacles for human consumption,
It can be hard to clean 3D printed items thoroughly. After a few weeks of use, you could have dangerous bacteria living in small cracks on the print. Mold growth is also a possibility and is extremely hard to remove.
Bacteria growth is a problem on items you plan to eat from more than once. It’s less of an issue if you print several disposable items. However, doing so wastes a lot of material.
If you want a long-term use print, then you’ll need to use a food-safe sealant. It can slow bacteria buildup, giving you more time to clean the print. However, you must understand that coatings of food-grade material still don’t guarantee it’s completely safe.
Overall, bacteria growth is a significant issue when eating off resin prints. Tiny grooves and imperfections in the print that you can’t see can house tons of dangerous bacteria.
Possible Chemical Leaching
Clinical studies have shown that leachable toxins may originate from any part of the printing process, including contact with printer components. Polymer additives are prone to leaching due to changes in crystallization and the risk of potential chemical contamination from the printer itself.
The resin cures and hardens after exposing the resin filament to UV for a specific time. Before curing, even plant-based resin is toxic. It’s only after curing that it should be safe to handle directly. Resin won’t leach chemicals after proper curing when it’s hardened.
However, it’s still possible for chemicals to leach out of the material. You might not fully expose objects with many grooves, ridges, or twists to UV light. That means the project may not cure everywhere.
The only way to know it won’t leak chemicals is to cure it carefully. Since there’s still room for error, it’s not a good idea to eat off of any printed resin projects.
Using Plant-Based Resin To Make Molds
All that said, you won’t need to get rid of your plant-based resin! It looks great and has a variety of uses outside of food. If you still want to make food items, you can print a mold. From there, you can fill it with food-grade plastic and let it set.
Overall, 3D printing makes it simple to create molds of anything! You can use your filament as a base to make plenty of plates, mugs, and utensils. Plus, you can use a mold several times before you need to print another one.
Alternative Food Safe Filament
Biodegradable polylactic acid (PLA) may be food-safe if the manufacturer doesn’t use toxic additives or color pigments. However, its high distortion rate under high temperatures makes PLA unsuited as hot beverage holders and dishwasher cycles.
Ceramic is a popular option for food-safe SLA 3D printing. After the printing, the mold is kiln-fired, burning out the resin and leaving the ceramic object. This process creates a genuine ceramic piece that’s strong and heat resistant. With added food-grade glazing, the part becomes highly resistant to bacterial growth and chemical leaching,
To summarize, even plant-based resin isn’t a food-safe material. Despite your best intentions, chemical leaching can occur at any part of the printing and curing process. If you take additional steps and coat the work in food-grade epoxy, it does help make it safer. However, bacterial growth is always a potential hazard, so you should take care.