Foodsafe Filament

I posted a question over a year ago about whether any filament was foodsafe. Nobody replied. I’m repeating the request because I’d like to print some things that would be used with food. I’m hoping there is more information available now about the food safety uses of 3D printing filament. Thanks for your help…

Mark -

There is no such thing as food safe fillament even if the starting plastic is 100 percent fda approved, simply because the printing process leaves microscopic voids in the part surface. You can either coat or treat the surface to make it food safety (food safe epoxy, acetone wash, etc) but no part off the bed is food safe. You may be able to get away with dry contact use, cookie cutters, etc.

Also most hot ends use brass nozzles that contain trace amounts of lead.

Ok, good point. But, since plastic utensiles, dishes, trays, storage containers, etc. use different processes like injection molding, they don’t leave microscopic voids in them? Or is it that they don’t use thermoplastics?

Mark -

So, I guess what I’m wondering now, is does washing with hot soapy water work as well with things we print, as it does with plastics that we buy? Or is the plastic we print toxic itself?

Mark -

The items you mention are either injected under pressure that doesn’t leave voids, or “blow molding” that results in a single continuous sheet with no room for voids. In both cases the starting material is injected at high enough pressure the voids are essentially non existent.

Washing with hot soapy water may not remove all food and bacteria from those voids, leading to botulism toxin risk. There are several good scientific studies on that if you are curious.

Tks for the feedback. I appreciate your opinion…

Mark -

I would like to throw in my two cents for a food safe filament.

You might want to take a look at:

Nylon 680 is used already in medical, dental, food processing, and robotics industries as well as it’s FDA approved as food safe.
You may also want to look at Alloy 910 which is also FDA approved, and with a little research you can find that Alloy 910 is used inside of human bodies on occasions in hips and for heart valves.

I use Alloy 910, and absolutely love it.

Keep in mind that most food containers are made with PET, which you can use to print.

The chemical properties of the fillament are not the issue. It is the microscopic voids in the print surface that are the problem due to the method of printing. Injection molded plastic pieces do not contain surface voids like 3d printed parts. You can NOT print a smooth uniform surface that meets FDA guidelines for a food container out of ANY fillament on a fillament based printer. Period. The mechanical properties of the printing process, even at extremely fine layers with a very well adjusted printer do not allow for a smooth enough, void free surface without either coating the surface, or treating it with some sort of solvent process to fill those voids. Medical applications are sightly different in that the material is used in an encapsulated environment, where human cells are expected to grow in those voids and interface with the parts. It’s not a situation like with food where you have particles of foreign matter deposited, exposed to oxygen, left to rot because you cannot clean the particles out of the voids, botulism starts to grow, then re-exposed to food, spreading the toxin.

Do not print food containers. You will make someone sick.

Hey Piercet, I appreciate your passionate response.

I would like to provide some proper information that was founded based on proven tested results rather than opinions.
I would agree with you that microscopic voids filling with bacteria is a valid concern, which is why you would not want to use a material that was not extensively tested and then approved for use.

You would want to print any material that will come into contact with food using a stainless steel nozzle.
This is a precaution, as some of the brass hot ends out there contain lead, and you don’t want that in your food material.
You will want to use a material that is dishwasher safe, just as you do now with your plastic containers.

According to the FDA:
Safe 3D printing materials for food contact (FDA approved)

PLA without additives
PET, PETG / T-Glass
ULTEM 9085
Natural grade Nylon 6 & 6.6 (without additives)

Unsafe 3D printing materials for food contact

PLA with additives → Ask your hub what PLA he uses
Nylons with additives (e.g. oilon or Mos2)
High impact polystyrene (HIPS)

You may not like, or for personal reasons agree with the results, but they are infact true.
Hell legos are made out of ABS, and kids put that in their mouths.

You can and probably should use Nylon 680, this polymer is unlike any you have seen in the past. Under development for over 8 months, it is FDA approved for applications requiring contact with food or beverages. This is because of its ability to handle high temperatures inherent with steam, boiling water and dishwasher usage. It is specifically developed for FFF 3D printing and like all of taulman3D’s filaments, it has a consistent melt viscosity
There’s also a FDA food safe approved PLA that’s designed to be washed in the dishwasher as well. Can’t remember the name right now.
You can download the MSDS from Taulman for instance and verify that it is in fact food safe. (which I’ve attached for you)

You can also seal it with a food safe sealant.

If you find yourself unable to sleep, there is an excellent read from 2014 when the FDA was getting involved in certifying and classifying 3d printed materials, in the minutes of meeting there are specific examples where 3d printed nylon was discussed for it’s many useful possibilities.

Jumping forward, here’s a link to the current material criteria for “Single and Repeated Use Food Contact Surfaces”.

If you keep searching, and I may update this post later with some other references you’ll find that it can be done safely.
Infact, it already is.
nylon_680.pdf (395 KB)
Additive Manufacturing of Medical Devices Public Workshop 2.pdf (634 KB)

Yes, there are plastics that are chemically safe for contact with food. There are plastics available in filament form that are fda approved. Fda has in fact issued guidelines for use of those materials with food. All this is true.

Nowhere at all has the fda issued approval, guidelines, or other direction related to 3d printed forms of those plastics. There is extensive research that 3d printed plastics of all types contain voids unless treated or coated that will trap food and potentially kill you. All the plastics you list as fda approved in fact have that same limitation. Suggesting to people that they can print a food safe item on their home 3d printer out of those materials is quite frankly dangerous.