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Danger of eating rust?


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January 16, 2009

In response to the rust issue. I looked up the MSDS info (which sounds very scary) but realized this must be some sort of industrial strength and quantity they were referring to. Then I looked up Iron (III) Oxide on Wikipedia. Here's the link:


Wikipedia may not be the best authority but I think it balances out the MSDS info. It's interesting that this compound is used in cosmetics and as an FDA approved dye. Also, at the bottom it says under biochemical uses that nano-particles are non-toxic. It appears to me that as long as we're not actually going out and finding large amounts of rust to eat that we'll be fine:)

Dana Persson
- Salmon, Idaho

sidebar January 24, 2009

Smashing! This is the second time that an odd search has taken me to this amazing site. I wish you WERE medical experts, since this site is generally better able to handle the obscure and far more interesting in tone than medical sites. Thanks to the last few posters for excellent documentation to support poor Ted's very practical and correct advise. I'm amazed that he doesn't go mad or close the thread entirely, but very grateful. I'll go make some tea in my rust dotted kettle now, with no further concern.

Mary Morris
- Duarte, California

January 25, 2009

Thanks for the kind words, Mary. Regards,

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

April 25, 2009

I just found this site while I was looking for an answer about the same question, "Will rust harm you if ingested?"
After reading many articles on the subject, the best response I read here was "It appears to me that as long as we're not actually going out and finding large amounts of rust to eat that we'll be fine:) heh heh.
This seems to be a really informative site. I'll be stopping by a lot in the future. Thanks!

Terry Lockwood
- Washington, Pennsylvania

June 7, 2009

Hello Ted,

I too want to say thank you for your answer and I am sorry you took so much heat for it. Quite frankly, you are in the business of finishing products, so I'm not sure why you are supposed to be an expert on the affects of unfinished/de-finished" products, but this thread has answered my concerns about ingesting rust, so thank you.

Sharon Silva
- Santa Rosa, California

Ed. note: thanks again to those who provided links & resources, and thanks for the kind assessment of our efforts.

August 27, 2009

Hi Dana, I went to the Wikipedia entry you provided and would like to amend the website address you supplied. The type of iron used in cosmetics and tattoo inks is Iron (II) oxide (2 rather than 3), which is common rust. Iron (III) Oxide (3) is known as magnetite. Wikipedia also states: "Iron pigments are also widely used in the cosmetic field. They are considered to be nontoxic, moisture resistant, and non bleeding." Visit en.wikipedia.org/wiki/Iron(II)_oxide or en.wikipedia.org/wiki/Iron_oxide for more information.

Rob Martin
- Palmdale, California

August 29, 2009

Hello everyone here, very nice website which I found, like a lot of you it seems, by Googling whether my rusty pan will kill me hahaha

All the answers here are quite good, Iron oxide as far as I know doesn't pose a major health risk in the doses that we're talking about....I'm Australian and half the dirt in my country is made of it!
I'd just like to add a couple of points. Can I first just reiterate and remind everyone that tetanus CANNOT be caused by rust. It is caused by a toxin produced by type of bacteria that may be found on rusty surfaces, but also other types of surfaces as well (say a dogs mouth or something else that's been on the ground), and is usually contracted through a wound (as I believe someone posted above) ! I believe you will never hear of it being contracted through consuming of rust :)
It's also easily prevented by routine immunization so please don't worry about this one too much.

The other thing I wanted to add to make sure people don't get the wrong idea concerns copper corrosion, which was also mentioned above. While iron rust doesn't pose a massive threat to our health, copper, and copper compounds(which commonly form on copper products exposed to air and water for a long period, you may see a blue-green and/or black coating on the surface) are toxic and should not be used to prepare anything for human or animal consumption. Copper is naturally found in the environment and is essential in our diet in trace amounts (which is already found in food, taken in from the soil), but anything above this should be limited.

here is a link to an Australian government fact sheet on these substances which has a little information and is quite easy to understand:


You can also look up a little more if you're interested, and I realise most people might already know this stuff, but I just thought it was important to clarify that iron and copper corrosion are NOT the same in their impacts on human health, since someone mentioned copper in the same thread here :)


Jess b [last name deleted for privacy by Editor]
- Hangzhou, China

September 28, 2009

Despite the diligence of the owners of this site, I have to take exception to many of the answers presented here.

"I'm 50 and I'm not dead yet" is not at all an acceptable answer to the original question of the gentleman from India, nor are any boorish references to curry. The post providing the MSDS was the first logical answer here, everything else was simply anecdotal and, therefore, useless.

Need I remind you all that science is the process of gathering large amounts of data to make statistical statements. You don't have to be a statistician to know that a single observation does not make for a good statistical statement. Furthermore, authority does not pass for truth. Having many years in the metallurgy business is good, but certainly a more informative answer, perhaps including theoretical or empirical evidence, was called for in this case.

Ryan Tierney
- Rochester, New York

November 28, 2009

Thanks, Ryan. I certainly agree with your science point! But I think that mankind using iron for food service for 3000 years without alarms sounding about ingesting rust is 'big data' not anecdote.

And we humans have limited time, with limitless things calling for our attention, so there's nothing wrong with answers to the effect that "with all the things going on, here's my take: this isn't an issue I'll spend my life worrying about". With non-inspected food being imported to America from every hovel in the world today, I'm far more concerned with listeria, e coli, or salmonella in my food than rust on my utensils.

People who join into this discussion don't incur an obligation to launch authoritative research projects; and providing space for questions here doesn't obligate me to the impossible task of authoritatively researching hundreds of subjects a day. If you feel that theoretical or empirical evidence is called for but lacking, please cite a study that found rusty stainless steel flatware to be harmless or dangerous; please don't limit yourself to criticizing others for failure to do so :-)

As for "boorish references to curry" : Freeman Newton doesn't ^didn't have a mean bone in his body and he certainly didn't mean offense to anyone. But he writes ^wrote very cleverly and was probably *too clever* in his allusion to the special renown that cumin/curry has long held for its exceptional iron content (well under an ounce offers more than 100% MDR of iron).

I hope that readers who now recognize this observation will re-read Freeman's response in a charitable light: "Also rust is iron in its NATURAL state ... and I wouldn't think that mini amounts of it would harm you. However, probably curry in excess might do so!" It is clever, warm, and friendly, besides putting into perspective the small amount of iron/rust ingestion we're talking about. Hundreds of postings of that sort made Freeman this site's most beloved and most dearly missed contributor.

Thanks again, and Regards,

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

December 4, 2009

This is quite a discussion! Still going strong after years! I looked in for the same answer - and found it. I like gathering numerous opinions and gleaning a consensus.
It's usually fairly easily to discern those with knowledge from the discussion. I understand what you mean about the critical statements, they seem to strengthen as time goes on, but those are usually from people who aren't really looking for dialog; they either love to be negative, or they are irritated at not getting their "way" (i.e. the kind of answer or info they hope to get.) In either case, they aren't considering any other input then their own as valid or important, OR they just plain don't comprehend the point made. Sometimes you just can't connect - you're best off to just let it go early. Unless of course you need their agreement for a sale! (don't know how to make that smile symbol)
We sell tools, and sometimes, you know, you just have to think, "Never mind".

Anyway, thank you for your faithfulness, it's apparent you love what you do!
P.S. so I'm now using the big old cast iron dutch oven I had outside as an ornament (rustic decor) ha,ha!
It's been consigned as THE popcorn pan - since our microwave died, not being replaced.
What I treat I forgot about- that fire popped corn!
It only is hard to shake - it weighs about 10 lbs!

I googled "cast iron rust" and found some great sites (and methods, and products) about restoring cast iron - also the chemistry of the iron, the rust, and the various cleansers was posted with chemical reaction explanations. Very interesting. Now I remembered that I think I failed to master the balancing of equations in chemistry. Something about taking an element from one side and putting it on the other, but it applies to cast iron and rust believe it or not!

Lynne Hamilton
- Menifee California

December 12, 2009

Just a quick note, which I find is lacking from an otherwise great resource:
"Ingestion of greater than 50 to 100 mg of iron per day may result in pathological iron deposition in body tissues. Repeated iron ingestion can produce cardiac toxicity" (my source is http://www.jtbaker.com/msds/englishhtml/i7500.htm)

One thing I learned in a toxicology class: "the dose makes the poison" Iron is not toxic in low doses, but it is at repeated and high doses.

So, instead of just dismissing the iron on your pots and pans, take a little time and clean them or season them. That takes care of the problem altogether.

Ana Rule
- Baltimore, Maryland

January 6, 2010 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Is it unhealthy to use stainless steel flatware that is showing signs of spotty discoloration (darkening, blotchiness, some rust color)?

Pat Van Wert
- Glenview, Illinois

February 13, 2010

Pat Van Wert:
Funny you should ask that; that was the original question that started this thread way back in 2003 - believe it or not. If you are interested in doing so, you may go back to the beginning of the discussion and see that question posed by a gentleman in India (I think) and it started an immense amount of dialog on the issue.

I was researching the idea in Dec 2009 when I found this site on google. I think you'll find your question well answered!

btw, for those who viewed my last response, the big old cast iron pot ended up burning the popcorn a lot, so it is now sitting next to our wood burner as a decoration!
I still have the "rustic" theme outside, but won't send it out there, I can use it for a stew sometime, or maybe even a camp pot.

Lynne Hamilton
- Menifee California

Hi there all of you....

hope all of you guys are doing fine and hope that your worries leave you

I'm seema, 28 female, Masters in Marketing from Karachi, PAKISTAN and bit of a paranoid person or maybe not!

Anyway my issue is that I just found out that my mum's old kettle which we use daily to boil water for tea/coffee is rusting like anything especially from inside. When I rubbed my finger on the inside base of kettle the orange color came off on my finger immediately. I am concerned, well actually scared because me and my mum have been drinking tea made from the same kettle in which the water was being boiled. Is it dangerous, guys? Could I, God forbid, be slow poisoning myself or my mum. We would never use it again for sure, but what about the fact that we have already spent so much time drinking tea made in rusted kettles. Can anyone help me and can you please tell me what are the early symptoms of metal poisoning coz I am allergic to artificial metal, could I develop more toxicity b/c of that or what! I do have few blisters on my tongue recently and had a small acne break out. Could it be a sign of poisoning?

I would really appreciate it if you could answer me to the best of your ability.

Thanks and Regards,


Seema Hamad
marketing - Karachi, Sind, Pakistan

November 9, 2010

I recently bought a conical sieve and a potato ricer on ebay, both of which have small spots of rust. They are very old. I ended up on this site as I was worried about consuming rust but now I'm pretty cool about it.
I read the thread from start to finish. There are some really strange lonely people in the world.

Thomas Sanders

November , 2010

Hi, Thomas. It's after 2 AM as I'm reviewing your letter and the family has been in bed for hours. I guess I'm one of those strange lonely people -- thanks for keeping me company :-)


Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

November 13, 2010

Thanks to all who have posted - my father is always looking for signs of rust in the kitchen. Not only his kitchen and assorted equipment therein, but everyone else in the family is subject to his rust-paranoia fed inspections. I look forward to referring him to this thread!

Mia Dobkins
- Ozark, Missouri, USA

November 27, 2010

My question about ingesting rust was answered in the beginning of this thread, but I couldn't stop reading. How interesting to see the variety of personalities and responses to the way the host answered! Thanks for the website!

Jean Horton
- Eugene, Oregon, USA

December 7, 2010

I had the same concern with rust on food equipment. I came across this site and read all the prior threads. I noted that there shouldn't be a concern for a small amount of rust but as a skeptic academic, I needed more supporting documents before I continue the use of my cookware. So I searched for several more hours for an answer that I was comfortable with.

I searched the government sites (many many government sites) that advises us not to consume food stored in containers with rusted lids or cans that are swollen, bulged, or rusted. Food stored in such containers harbor bacterias that cause lockjaw (tetanus).

My search for "the" answer ended when I found "Ask a Scientist" provided by the DOE Office of Science for users to post science related questions. The following Q&A was found at http://www.newton.dep.anl.gov/askasci/mole00/mole00756.htm

"Question - I know the USDA does not allow rusty equipment used in processing plant but I want to know what effect does rust have on pathogen growth? I'm thinking rust is considered as free-radical--bad for your health--and bacteria loves iron but how much is too much? A piece of meet placed on rusty equipment gets cooked on high heat--how does heat affect it?


I am pretty sure that rust is not a free radical; it is Iron Oxide which is not chemically reactive. Iron bacteria are not usually pathogenic so I don't think rust in food preparation equipment is of much concern.

Ron Baker, Ph.D."

Tiff O'Hare
- Linthicum, Maryland, USA

January 26, 2011

I have enjoyed reading these comments very much and I am reassured that the more recent posts have been more objective and respectful.

I was seeking an answer to why soldiers (Vietnam war) were told to discard their water canteens if rust was present because it would cause dysentery. Clearly it is not the rust itself, but the likelihood that bacteria can colonize the rusted area.

It seems to me that if rusted cooking/eating implements are sterilized, they will still be rusty but will not be a health hazard.

Meg Coisey
- Perth, WA, Australia

June 12, 2011

The body has no mechanism for excreting Iron, so toxicity is determined by the amount already in the body. The real danger comes from combination of sources of Iron, such as supplements + rust intake. Kids are more susceptible to most forms of Toxicity, so if children are involved consult a doctor or replace the rusty items.

As noted above, the primary cause for concern about rust is that the small pits and valleys will encourage bacterial growth, and lead to the possibility of food poisoning.

If you are taking supplements with iron and have some rust intake, then you should consult a doctor. If most of your cookware is rusty, you should replace or remove as much of the rust as possible.

Since the best solution is to remove the rust, this could mean sandpaper or other abrasives. These will cause more pitting/scratching of the cookware (etc.). So make sure to dry well after washing to prevent any future bacterial growth. For cookware, you can use your stove (on low) to accomplish this without missing any areas if the cookware is really pitted. Cookware placed on the small element for about 10 seconds will usually finish drying anything that was partially dried already (dishwasher or towel dried).

The effects of Iron Poisoning:

If you are having these symptoms, you are getting too much iron in your diet, and your body cannot get rid of it. See a doctor immediately.

Chris Whiting
- Sebringville Ont. Canada

August 23, 2011

My wife recently prepared a large amount of chicken and rice. The quantity was so large she couldn't use her standard tupperware containers. So she put the meal into a large tin coffee can. The inside of the can immediately started rusting. Is this a safe way to store wet leftovers?


Jack Shry
Hungry eater - Franklin, Virginia, USA

August 23, 2011

Hi, Jack.

Sorry, no, it's not. Coffee cans are designed for dry foods and vacuum storage.


Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

October 12, 2011

I grew up in the mountains of Wyoming eating out of cast iron cookware, drinking from pots and troughs with more rust than metal, and tending the sacred graniteware coffee pot that was 2 gallons at least and never, NEVER, washed. (Any self respecting cowboy simply added grounds until there was more grounds than water, then scooped out some of the waste, and continued on. My grandparents and great uncles and such, all doing the same, lived well into their nineties. Most of us haven't been to a doctor in decades.
While there are many things that can kill you and make you sick, like the stuff that comes from a fast food restaurant, I doubt that the rust will do us in. There's far more deadly compounds in city water than there are in an old fry pan or water dipper. If you want to be scared, lead was used until recently to solder and fit all city water supply pipes. There's a lot more lead in your drinking water than rust in your fried eggs. And don't think bottled water is the answer since most of that comes from other city's water, read the label! By the way, did you know that Teflon and bleach, two items found in almost every American kitchen, are among the most deadly compounds known to man?
Stop worrying, enjoy life!

Steve Starr
- St. Louis, Missouri, USA

December 3, 2011

I found this discussion after discovering that a hand-held blender had rust that was spinning into the baby food I was blending and have found the info and links very helpful.
I'm not too good with the internet and was wondering if iron from something like cookware or my blender is the same as you get in your blood (to date wiki isn't real clear on this).

Also out of pure curiosity, when was the first question posed?

Jade Smith
- Adelaide, South Australia, Australia

Ed. note: this thread began in 2003.

January 6, 2012

I came across this site because like everyone else who has responded, I was worried about cooking with rusted pots and pans and silverware because about a week ago I realized that my frying pan had scratches on the bottom of it and the scratches had began to rust. I continued to use it because I just moved into my first apartment and it was my only frying pan. A couple of days after realizing it was rusted I got very sick my throat got swollen as well as my tongue, I started to feel dizzy get headaches, etc... I thought I was poisoned! (lol) Paranoia got to me.

So I went looking it up on the internet and I got to this website I took the advice got relieved! (wasn't worried about the rust anymore THANKS TO THIS WEBSITE!!!) =D

I started to feel worse, I was getting light headed and weak so I went to the E.R. and it turns out I had a bad case of the Flu. Lol! But I thought about this page (and asked the doctor before he told me it was the flu) about rust, he literally laughed at me and said "unless you are eating rust like its candy, its harmless. Rust is definitely not the problem."

So I hope the fact that I got a doctor's advice on this topic will help everyone who still had doubted whether rust was dangerous and hazardous or not. Might I add that I got so wrapped up in this thread and the responses that some people made; I couldn't believe it soooo negative! For what? With that being said I also want to add that the fact of everyone being so quick to be negative and judge others that they don't even know is wrong and shows how quickly people get amused by negativity. I don't think neither Ted or Jimmy was wrong I think Jimmy didn't understand Ted's reply and just wanted to be extra careful and Ted was just being honest and upfront. I definitely don't think any of Ted's replies was wrong, disrespectful or out of line! =) this site was lots of help!

Thanks for being here for everyone and thanks for letting me post an answer and give my opinion!


Jasmine Santana
- Brooklyn, New York, United States

January 10, 2012

The MSDS includes-- "Ingestion: May cause severe and permanent damage to the digestive tract. May cause liver damage. Causes severe pain, nausea, vomiting, diarrhea, and shock. May cause hemorrhaging of the digestive tract. The toxicological properties of this substance have not been fully investigated."


Beth Greene
- Bismarck, North Dakota USA

January , 2012

Hi, Beth. That MSDS is for Iron [III] Oxide, 99.999%, -100 Mesh not for rust. It also says, for example: "Facilities storing or utilizing this material should be equipped with an eyewash facility and a safety shower."

To put it into perspective, that same MSDS says --

Clean Water Act:
- None of the chemicals in this product are listed as Hazardous Substances under the CWA.
- None of the chemicals in this product are listed as Priority Pollutants under the CWA.
- None of the chemicals in this product are listed as Toxic Pollutants under the CWA.

- None of the chemicals in this product are considered highly hazardous by OSHA.

California Prop 65
- California No Significant Risk Level: None of the chemicals in this product are listed. Let's not work hard to terrify ourselves :-)


Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

January 11, 2012

I'm not working hard and I'm certainly not scaring myself. Point is that you gave an irresponsible answer by completely failing to acknowledge that there is any potential for harm at all.

Additionally, there SHOULD be an eye wash station - do you not know that even a very small amount can harm the eyes significantly? Furthermore, are you not an engineer? What then qualifies you to give people such absolute advice about health concerns?

Beth Greene [returning]
- Bismarck, North Dakota USA

January 12, 2012

Hi again Beth. I gave no one "absolute" advice; I offered personal opinion & personal experience because running a public forum obligates me to not ignore people who take the time to post questions. Dozens of other people posted their opinions, you've posted yours, and I continue to encourage everyone to contribute any info they can.

You're welcome to install an eyewash facility & safety shower in your kitchen to deal with rust spots if you feel there SHOULD be one, but I'm not going to install one in mine. Have a good day :-)


Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

January 23, 2012

Ted, Thank you for posting this thread! Nine years since the question was first asked, and I was able to find the answer to my rust question, being entertained and educated in other areas as well along the way.

For example, thank you to Kate M for the Cream of Tarter cleaning tip. Unrelated to the search for my original question, this tip saved one of my pots from the trash. (Did you know you really CAN burn water? I thought I ruined one of my pans, but Cream of Tarter and just water and a paper towel removed the blackened residue that nothing else touched!)

Thanks to all who clarified the tetanus questions. I work in a health care profession and once treated an older woman in the hospital with tetanus from a puncture wound she sustained from a twig while gardening. She cleaned and bandaged it and thought nothing more, but ultimately ended up in a life-threatening situation and a very long, painful recovery. So tetanus doesn't have to come from a rusty nail, or even rust, but can come from even a dirty twig. It is not the rust, but the bacteria that causes tetanus, as people have already clarified in previous posts. To avoid this, keep current with your tetanus boosters, or at least get checked out if you get a puncture wound. As we get older, we forget about these things (at least I do, and so did that unfortunate older woman I mentioned.)

Beth G: Don't get over-uptight about the MSDS. Government regulations require the worst possible scenarios for every possible chemical, kind of a CYA measure in a law-suit-happy world, and one where some people are just plain idiots and don't have the least bit of common sense. Did you know there is a similar warning in the MSDS for table salt as there is for rust? I have enough common sense to not need an eyewash station in my kitchen.

Ted: I in no way found any of your responses to be rude, condescending, etc., but just plain honest and straight-forward. I will though, in Jimmy's defense in the very first post, have to admit that I don't take everything as fact on the internet. He doesn't know (nor do I) your credentials, your experience, or your level of expertise, so I don't find his request for further documentation unreasonable. He may not have realized you don't have direct access to the articles/resources he assumed you got your information from. Personally I am grateful to all the other readers who posted links to some great resources. I like to back up anecdotal experiences with actual facts, especially when I don't know the source personally. We never know who is actually posting information on the internet.

Cami Lyon
- Yorktown, Virginia, USA

January 23, 2012

Hi, Cami. Thanks so much for your kind view of everyone's comments, including mine and Jimmy's. I certainly agree that the internet can be a questionable information source, so people have to double-check what they read.

Regarding "being entertained", the "patron saint" of my field (electroplating), is Michael Faraday ("Faraday's Law of Electrolysis", and much else), who had this to say:

"The most prominent requisite...is a good delivery; for though to all true philosophers science and nature have charms innumerable in every dress, yet I am sorry to say that the generality of mankind cannot accompany us one short hour unless the path is strewed with flowers."

I'm one of those "generality of mankind" types who appreciates the little flower-strewn side trips the posters often take us on, including your interesting and informative interlude about tetanus-laced twigs. Thanks!


Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

February 3, 2012

I have a pan that the teflon came off of and is now becoming very rusty. I use it to cook almost everything in. Will it hurt my family if I continue to use it?

Renea Layne
- Springfield, Ohio, USA

February 3, 2012

Hi, Renea.

After 60+ postings on this thread I hope you realize that you will get people's opinions, not objective fact -- because there are no "facts" available about an old pan of unknown brand, unknown metal, unknown age, with an unknown Teflon-like coating, that came off for unknown reasons (did it get so hot that unknown volatile compounds gassed out of it?)

My own personal guideline is that I try not to use surfaces for food service that were not intended for food service. The surface below the erstwhile teflon coating was not intended to be used for food service, so I would not use it for such. If it were my pan, I'd say time to discard it and get a new one.


Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

March 9, 2012

Hi guys,

This a really fascinating topic, and well-attended, too. I couldn't resist the urge to add my input/further questions, though. ,:D

I came to this site because my family uses an old Chinese wok extensively. My mom would tell me the dark outer coating is iron and good for you (since you need iron in trace amounts). It's been used for many years, however, so some of the dark metal has begun to scrape off at parts. For some reason, I have always thought of the dark coating as rusted iron; probably because I thought the dark, pitted look would only come from iron that has changed and processed through a gradual chemical reaction. As a result, I had been wondering about the safety (and benefits, but mostly safety) of ingesting a bit of rust everyday. Now, however, I realize that the black coating is probably NOT rust since a coating of rust would look actually very red and ugly... (looking into it now, the black coating is probably the "patina" of carbonized oils that wok enthusiasts talk about); so I don't have to worry about my mom ingesting chunks of rust every day, harmless or not. Nevertheless, where the patina has been scraped off by wear, the metal underneath has a dark, reddish hue and the water comes off with a dirty orange-red hue when washed. Is /this/ a thin rust coating, or something else? I understand that the staff of this forum work as finishing authorities rather than "de-finishing," but input from anyone who might know would be much appreciated.

If it is rust, though, I'm not much concerned since it's just traces of a thin layer rather than actual chunks of a crust being ingested. Nevertheless, after going through this thread, here are my own unnecessary conclusions about ingesting rust:

Eating small amounts of rust itself on your cooking/eating ware won't harm you.
It is possible to overdose on iron, if you eat a lot at once.
The presence of toxins from the original metal, as well as bacteria, in correlation with the presence of rust raises concern.

And here is my question:
What qualifies as "small amounts" of rust which are safe to consume everyday, and where is the line which marks the beginning of unhealthy consumption, leading to this....:

(can be caused either genetically or by gradual overconsumption of iron, it seems)


I know I can probably find a value which makes sense to me (e.g. a tablespoon of rust a day) based on the value a previous poster gave, but of course if someone knew and kindly informed me without necessitating my research, that would be very nice. I read elsewhere that the LD50 (median lethal dose) for rats is 30 g/kg. If I had the same LD50, then I suppose it would take 1500 g (1.5 kg) of rust in one dose to kill me. But is it the same number for consumption over a lifetime? Or, because iron (III) is mostly insoluble, it would take many more small doses than those adding up to 1500 g?

If I still thought I or my mom were eating chips of rust layer everyday, I would worry about this in application of my own life (or as an explanation of my mom's symptoms); but since I've tentatively averted my mistake, I'm not. The principle of this, however, is that any layperson could formulate a valid question about the gradual overconsumption of rust.

Whether or not overconsumption is a practical possibility in actuality, we don't know. That's because every assurance that it's NOT a practical possibility thus far in this thread has lacked: 1) a qualification on what counts for "that" in, "no, it's crazy to think that will damage you over a lifetime" and 2) a basis in actual scientific findings or even simple reasoning. The fact that we have no confidence in the assurances as a result is what makes the resurfacing question about ingesting rust a valid question.

Which isn't to say that I'm demanding that research be furnished for me right now. I am only pointing the validity of the question out because there seems to be an assumption that the question is no longer justified because it's already been answered anecdotally. It's fine if you think the question is getting old because it's been established that no one will here will bother answering you well by now; but I disagree with the sentiment that the question is stupid because it's been answered well enough already by others.

In other words, it's OK for you to offer your opinion, but you shouldn't assume that you have /answered/ the question well, and then use that assumption as the basis for condescension when the question is asked again.

Anyway, I realize that I probably sound a little militant and that Ted has already asked for a stop to the ad hominem discussion, so this may not be posted. Nevertheless, a little side dialog about how questions have been answered (which is very much circa hominem) has been going on for a while now, so I wanted to address it with my own input. If even only the administrator reads this, I will be satisfied that my ideas were communicated. :)

Rona Chong
- Modesto, California

March 9, 2012

Hi, Rona. Thanks for your contribution to the dialog. Yes, I follow your point that the chronic use of rusty serviceware may be different than rare use. And everyone is welcome to their opinion, whether repeated or not, and to answer any question they wish or ask any question they wish.

It's not that I feel the concern is stupid, nor do I think that my opinion is anything but my own opinion. But, although there are countless threads on this site where I've been corrected and changed my mind, the truth is: after 9 years and tens of thousands of readers and a hundred postings, I hold the same position on rusty utensils that I held back then: that rust is either not dangerous at all, or so very minimally dangerous, that it doesn't merit my "apprehension". Yes, this may be as much a philosophy of life attitude as a science answer.

Thanks and Regards,

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

April 29, 2012

With regard to rust or anything that comes in general, I feel we should focus on the nature that gives the best food. It is better to avoid what is visible and that feels not good for you as it will effect you mentally. I eat anything and any kind of water as long as it gives the same taste. Sometimes I feel sick but still I am strong enough to fight it. Taking more precautions will give more troubles and you will be weak day by day and you will not be able to fight any sickness. I feel that nobody can control the nature but balance by itself. Imagine the people who have not seen a kitchen or cooking but digging garbage to get some food are still on this earth and they do live. Some get sick as they eat only poison but some still healthy when they select natural food out of visible poison. So why worry for rust. It is needed by human body I think. Listen to the body and eat whatever you feel is the best I believe. Anyhow, we eat the best food on the earth but still we will die, so why worry. Enjoy, and die without worrying is the best thing I think we should do.

Nimal Dias
Supply & service of Catering and processing equipment - Sri Lankan in Dubai, UAE

May 14, 2012

Hey, Ted, is it okay to eat food off of my grill if my heat plates are rusty?

Ross Stoeve
- Milwaukee, Wisconsin USA

May , 2012

Hi, Ross. In my own estimation, yes.

I rarely see any flame deflectors that aren't badly rusted.


Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

June 1, 2012

I came to this site after noticing rust in the old pans I've been using to plant herbs in. After going through most of these posts, I just called Poison Control, explained that I was eating basil grown in rusting pans and that I'm in the second trimester of my pregnancy. The pharmacologist who took my call assured me that iron oxide (rust) is not toxic--it is simply the left-over material of the metal that is being oxidized (he said it better). When I reminded him I was pregnant he repeated I had nothing to worry about and that the only reason I would need to toss the pan/planter was if the taste of the basil was ruined.

Great site, Ted--I think your responses are more even-keeled than mine would be if I were hosting this thread.

Elaine Read
- Atlanta, Georgia, USA

June 26, 2012

A. Greetings,

I'm a younger fellow, arguably part of 'The Entitlement Generation' that has come into adulthood this past decade, with my contemporaries eagerly waiting for their posh white collar jobs directly egressing our 4 years of paid collegiate high school after-party.

I was curious about eating rust and, I too found you to be near the top of google's results. And I got a sour taste from all the people expecting you to provide these inclusive, academic results for their own whimsy. Somewhere we entered this default behavior that we must cite each claim we make with notarized evidence. We don't treat each other like neighbors; instead we are now each competing news anchors, apparently.

I had refinished an old scythe and got rust all over my hands and was eating a bagel directly after. I thought to myself "gee, I wonder if over the past billion years we ever encountered this and got genes that could handle some rust". This is pretty much how I try to squash my modern paranoia- "did this happen to a caveman? yes? then I shouldn't worry about it if I didn't just die from it."

Thanks for running this forum with a refreshing, no-nonsense attitude.

Mike Cross
- Lee, New Hampshire, USA

Ed. note: Thanks for the kind words Mike.

August 9, 2012

Went looking for info on whether rust in the bottom of my electric kettle is bad for me and found this thread. Immensely entertaining reading! Bottom line is commonsense....

1. Rust is basically harmless.

2. You can't always be sure it's purely rust.
-- With a non-stick fry pan, there could be teflon or other chemical coatings mixed in with the rust.
-- With an item that has been not washed for a long time (rusty nail or tool), it could have bacteria on it.
-- With an item that's been scrubbed with an abrasive surface, bacteria could be hiding in crevices and escape cleaning.

3. When in doubt, throw it out. New kettles are cheap! :-)


Abby Obenchain
- Sault Ste Marie Ontario

December 3, 2037

Well, it is now 34 years since the original post and I thought that I might say that I'm still finding it interesting and informative in 2037!

Way back in 2012, Abby from Ontario suggested:

3. When in doubt, throw it out. New kettles are cheap! :-)

Well, if only back then, we hadn't turned so much serviceable and well made cookware, of higher grade materials into virtually unsortable mountains of 'waste'. All for the appearance of newness or resolving of doubt too! Now, so many years after peak energy, we would love to still have one of those rusted or limescaled products to care for and use. Instead, those cheap new kettles were indeed that. Cheap. What crazy times they were, yet how amongst the disposable worries of the early 21st Century, wise advice like Ted's still holds true.

Right, I'm off to descale this elderly Le Creuset kettle, glad that I helped it survive through that short sighted and short-lived age of waste and opulence.

Thanks for the metal-care tips! They endure!

Yarof Spring
- Newcastle, UK

sidebar November 23, 2012

Q. Is there such a thing as redoing the finish of stainless steel flatware? NOT IN FEAR OF DISCOLORED SPOTS but just to return the original shiny appearance. And if yes, would the cost of redoing approximately half (20ish pieces) of a set of 45 pieces or is it better to just buy a whole new 45 piece set?

Walter Arthur
- Newburgh, New York

January 2015

Rock Tumbler

Affiliate Link
(your purchases make finishing.com possible)

A. Hi Walter. You may have seen "rock polishers", which are basically a coffee can with a little motor and roller mechanism that rotates the can day and night with a mild abrasive that slowly polishes the stones. There are much larger versions of this that are used in industry, called abrasive tumblers. There may be a service somewhere that tumbles stainless flatware in them to repolish it, but I'm not personally aware of such a service. If you can find one, refinishing will probably be affordable.

But if the shop has to rely on manual polishing with buffing compound and buffing wheels, you probably will find the repolishing prohibitive because of labor cost.

A third alternative is to try to do it yourself; try a Dremel or a small battery powered drill with buffing wheels and polishing compounds. It will probably take a long time, and require multiple wheels and grits, starting with a large grit, then a new wheel with a medium grit, and a new wheel with a fine grit. If you enjoy doing it, it's not prohibitive; if you consider your time worth money and you don't enjoy it, it is prohibitive. Best of luck.


pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

April 23, 2015

Q. I used a pizza pan to cover a pan I was cooking stew meat in. It was cooking for about an hour and a half. When I checked on it and pulled the pizza pan off it was coated with red rust. I couldn't see any but a little spot in my pan of stew meat but now I am worried it dripped all down in my pan and my children and I are going to wake up sick. Will we get sick from eating the stew meat?

amani osman
- grandville, Michigan USA

April 2015

A. Hi Amani. You are going to be fine. Rust is iron. You're not going to be sick.


pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

February 28, 2016

A. Rust is the process of metal oxidation. It is a chemical burning undergone by iron. Rust can happen when metals are in contact with water, air, oxygen, or acids. The main catalyst of metal rust is water, because its molecule can penetrate pits in any exposed iron. When metals are exposed to the corrosion-causing agents for quite long time, some of the parts will turn into orange-colored powder, known as rust. This substance has long been blamed for some health disturbances. One of the common disease people believed to be caused by rusty metals is tetanus.

Rust is oxidation of an iron. Most people believe that when you have a wound caused by rusty metals, such as a rusty nail, you are likely to suffer from tetanus. This is a deadly disease caused by bacterium called Clostridium tetani. This bacteria live in an anaerobic environment, usually surrounding the place where rusty metals are located. As to the discussion whether or not rusty metals cause tetanus, the answer is no. Rusty metals do not cause tetanus. It means, if you touch rusty irons with your bare hands, you cannot be infected by tetanus because of this.

It is not the rust itself causing tetanus. Tetanus is caused by bacterial infection. If you ask, why a wound caused by rusty metals carries tetanus, you need to know that it is not the rust which has something to do with the disease. Instead, it is the bacteria. The spores of Clostridium tetani live in humid, dirty places, such as soil and compost. These spores can shift their habitat from the soil or manure to the powdered rust. The dry, rusted area of a metal is a suitable anaerobic area for the spores. When the spores move, this rusty metal is contaminated by the bacteria causing tetanus.

When you have a wound caused by the rusty metals, the bacteria which contaminate the rust prior to the accident migrates to your body through your open wound. When you have a puncture wound caused by a nail, for instance, it is not the rust on the nail risking you to tetanus. Instead, it is the bacteria inside the rust who do so. This bacteria soon get into your body, spread through your blood stream, ends in your nerve system. Here, during the incubating period, the bacteria release toxin that induce nervous system disturbance.

Clostridium tetani-induced nervous system disturbances will cause locked jaw, neck stiffness, body irritability, high fever, and swallowing difficulty. Prolonged pain killers used to fight these effects can cause kidney failure and heart attack, which further lead to death.

If you happen to cook with a rusty iron pan, you might wonder whether you will get cancer or food poisoning, because rust seems to be a kind of issue. In fact, cooking with a rusty pan does not necessarily put you in a risk of become poisoned. Rust in a pan or wok will be harmful only if you cook something highly acidic, and in fact, nothing you cook will be in this criterion. Thus, the iron you might be eating because of the cooking process done with a rusty pan will be excreted by your body.

However, this rusty pan will be harmful if it contains bacteria that induce tetanus infection. Yet, Clostridium tetani is rarely found in the kitchen. Thus, all you need is to scrub the rust to eliminate it from the pan so that you can cook without worries of getting infected.

If your rusty kitchen utensils are contaminated by tetanus-causing bacteria and you cook using these utensils, you are likely to be infected with the deadly disease. The bacteria, in fact can go through your digestive system and infect your body. This will start the same cycle with the one when the bacteria goes inside your body through an open wound. Therefore, it is wiser to throw your rusty pan away, rather than put yourself to the risk of the deadly tetanus.

Gary Gelissen
- Blackshear Georgia, United States

July 28, 2016

!! Iron poisoning can also cause type 1 diabetes (insulin dependent, or juvenile) and can contribute to other problems also.

It's probably not as hard to get iron poisoning as you think, especially in children. I got iron poisoning as an infant simply because my mother ate a whole lot of iron rich food while she was still nursing me.

I just bought s $2k stainless steel vegetable juicer and wanted to gather information to get a better argument as to why I am returning a part that shows small patches of rusting. Now I am further convinced I should return it:
1.) My body does not tolerate any additional iron.
2.) The rust is on an inside portion that is difficult to reach and clean which could easily gather bacteria.

I certainly agree, that those who said that "I eat this stuff and I'm not dead yet" had a very weak argument. By way of example, Vietnam veterans exposed to agent orange did not develop type 2 diabetes instantaneously after being exposed. But the US government compensates those Vietnam Veterans exposed to agent orange when they get diabetes because it has been shown to contribute to the illness several years after exposure.

The later comments were more helpful.

Mandy Last
- Fairfax, Virginia, USA

July 2016

Reference Daily Intake

Agent Orange

thumbs up signHi Mandy. I agree with your desire for more fact and fewer anecdotes. Can you give us article titles regarding iron poisoning causing diabetes if you have any please? Can you offer us a chart or comparison between the 18 mg RDI [Reference Daily Intake] for iron and the quantity of rust that can come off a surface under some condition or other so we have a sense of whether any realistic amount of rust ingestion can exceed the RDI?

I don't think it's particularly helpful to try to compare iron (an essential nutrient, one of the most prevalent elements on earth, a building block of civilization so essential that we've named the whole modern era after it, and a kitchen material that has been used for 3000 years) to Agent Orange (a biocide engineered to be as destructive to life as possible, and rushed into use for warfare). We were trying to destroy the foliage that concealed snipers so that we could shoot or bomb them, so no one was concerned over their long-term health -- unfortunately we weren't sufficiently concerned about those deploying it :-(

Thanks for your input.


pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

June 20, 2020

A. Hi, like many, I came across this page while Googling for whether ingesting rust is harmful to health. I came for the answers but stayed for the interaction! It's amazing this thread has lasted so long and stayed on topic. Good job to the moderator/s (who I'm assuming is Ted).
I'm posting because I found relevant information from a reliable source so here it is:

"Though rusty water may look and taste unpleasant -- and possibly stain sinks and clothing -- it is not a health concern. A possible exception is people with hemochromatosis, a rare disorder that causes excess iron accumulation in body organs."

That's from https://www.berkeleywellness.com/healthy-eating/food-safety/article/rusty-water
And the top of the page states,"Medically reviewed by faculty at the UC Berkeley School of Public Health".

So there you have it folks. I hope that puts some minds at ease! It's specifically about rusty water but I think we can reasonably assume the same of ingesting rust from pans, other cookware or flatware.

Marianne Wong
- Singapore

June 2020

A. Thanks for the well-sourced quote, Marianne. It goes a long way toward separating fact from anecdote :-)


pic of Ted Mooney
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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