It isn’t easy to walk down the aisle of any sort of food store without ever coming across something made of different types of plastics. From jars of jam, jellies, and marmalades to bottles of soda to cookie plates, your food is in close contact with a certain kind of plastic.
One that has been specifically engineered for the express purpose of acting as a container of food items. This plastic is known as polyethylene terephthalate or PET.
PET and its derivative, PETG, also have some excellent properties that make them both a good choice for 3D-printing filament that can act as a container for consumables. Here ‘G’ in PETG stands for ‘Glycol-modified.’ This is a very clear form of plastic used for 3D printing because it is less brittle and more durable than conventional PET.
Is PETG Food Safe?
Many conventional 3D printing filaments are made of chemicals that react to hot food’s hot temperatures. Making a 3D mug, for instance, would mean using it for steaming hot tea or coffee.
While it is true that many manufactures tend to list their filaments as being inherently food-safe, you should still refrain from treating it as the “gospel truth.”
It is a good idea to check the manufacturers’ material safety data sheet (MSDS) for FDA approval before you get that filament.
IS 3D Printed PETG Food Safe?
To all extents and purposes, the American Food and Drug Administration (FDA) considers PETG to be safe for jobs that require contact with food items. However, here it is pertinent to note that they are probably thinking along the lines of injection-molded and vacuum-formed parts.
As a matter of fact, even if a specific filament material is considered genuinely food-safe, that still does not mean that each and every 3D printed part made from that particular filament will also be the same. After all, there will almost always be an abundance of nooks and crannies that will become breeding grounds for bacteria.
However, frequent sterilization of the utensil might render it absolutely safe for use even if created via the PETG 3D printing process on even an old printer. This is also important from a food safety viewpoint.
There is a huge number of safe material filaments currently available on the market for the modern 3D printer, including FormFutura’s HDglass (this is a highly transparent and modified form of PETG). Apart from that, German RepRap’s PP Plastic gives the FormFutura a run for its money. You should get those for your builds.
There are plenty of other things to consider when you decide to start using new PETG to make food carrying utensils. Some of them include the following ones:
Additives in Filament
The base filament itself might have been food-safe, but if the manufacturer had decided to add new and different chemicals or material in it, there is no telling how they might react with hot food and drinks.
Some chemicals are known carcinogens and unfit for human consumption. In this case, it would be a good idea to keep well away from filaments that use additives you know nothing about because they might not be food safe.
Small Holes Lead To Bacteria Buildup
This is a major issue with any FDM 3D printers. When making a food-safe build, small holes must be kept to a bare minimum during the 3D printing process. Food gets stuck in these holes, and before you know it, bacteria finds, thrives, and reproduces there. Eventually, eating with or using such a 3D printed utensil will mean being exposed to E Coli, Salmonella, and other lethal bacteria.
If you will be using new PETG filaments for 3D printing purposes, it makes a lot of sense to wash them thoroughly after use and before using it. Apart from that, you have to make sure that your 3D printing build is high-res enough to minimize or eliminate small holes.
Brass Nozzles Contain Lead
The brass nozzles of many new PETG 3D printers contain lead, leading to lead poisoning if exposed to above normal doses. It would help to get a 3D printer that would be using a high tensile plastic nozzle or any other safe metal.
Sealing Printed Parts
You would need to be using certain chemicals to seal the 3D print PETG part so that it would be able to maintain its waterproofing and structural integrity. Here, you will have to ensure that the sealant you get is also food safe and FDA approved for food safety purposes.
How Long Will The Printed Part Come In Contact With The Food?
Food contact duration is also an essential consideration if you want to make your prints safe. If you are going to get jars and bottles for long term storage of perishable and consumable items, you should be aware if they leech certain chemicals over a period of time during their contact with food. However, this should not be an issue if you want to use food-safe PETG for single use only.
In light of the above, we can conclude that plastic PETG is food safe in many cases, provided all due precautions have been taken beforehand.