Is Galvanized Steel Poisonous?

A. Hi, Vic. No, it's not "safe" because zinc is not a "food-safe" material. There should be no contact between food and galvanized surfaces. That is because acidic foods can dissolve zinc and we don't want the situation of people eating the dissolved zinc, and the possibility of overdose.

Again, zinc is an essential nutrient not a poison -- but you don't make coffee cups out of aspirin, or rotisserie spits of zinc :-)

Regards,

A. Hi, Jason. Zinc is not a food-safe material. The temperature doesn't matter, food should not directly be mixed in or skewered onto zinc. That doesn't mean it's a genuine hazard, just that guidelines say we shouldn't do it.

Regards,

A. Hi, Carol. Don't inhale the fumes, they could possibly give you flu-like "metal fume fever", but you surely don't anyway. I don't know 100% about zinc damaging kiln bricks but I seriously doubt it.

Regards,

A. Hi, Joey. I personally doubt that it's any problem. The enclosure is not a food surface. But paint fumes are not good. Get it good and hot without food in it a few times first.

Regards,

A. Hi, Shelley. The feed troughs and watering troughs on many farms are galvanized; people in remote areas have collected rain water off their galvanized roofs for many purposes, including drinking, for decades; and a great deal of water piping (maybe most water piping) was galvanized until a few decades ago. I personally don't think there is any danger whatsoever, but if anyone thinks there is, they are encouraged to post the reason for their concern.

Regards,

A. Hi, Catherine. Galvanized fencing is fine. When we say it's not "food-safe" we mean you should not cook in zinc pots or serve food out of zinc containers because of the possibility of acidic food or drink dissolving the zinc, and you consuming too much of it. Zinc is not poison, it is an essential nutrient; cold prevention tablets are one example of the deliberate consumption of zinc.

Regards,

A. Hi, Jeff. Most industrial facilities have exhaust systems and fume scrubbers to clean up emissions from processes like these. If you can see and smell fumes, and find them objectionable, in most areas the state EPA will make the shop correct the problem under a nuisance clause even if they do not exceed emission standards.

We can't even definitively say whether carefully monitored things consumed in definitively measured amounts like coffee, red wine, and milk are good or bad for you -- the answers seem to change every few months. So to try to estimate the possible side effects of an unknown amount of fumes from a process you're not familiar with, that are controlled to an unknown degree, on someone in an office in a different building across the street is simply impossible. Sorry.

Regards,

A. Hi, Dale. As noted in the beginning of this thread and a dozen like it, everything is relative. The amount of zinc exposure from this sounds reasonably minimal, and zinc is considered non-toxic.

What would concern me far more is the possibility of pinhole leaks in your piping which, depending on whether the section under the coals is on the suction side of the fan, could draw carbon monoxide into the house.

Regards,

! Ted,
Thank you for the answer and your concern at this point in time the piping is still new, I have planned on it burning through in a season or two so I will be checking it regularly. Thank you again this site has been very helpful and educating.

Thanks

A. Hi, Catherine. No, it won't.

Regards,

A. Hi, Alex. Although it is bad for welders to breathe zinc fumes, and it may be bad to put acidic foods into contact with zinc because of vaguely possible overdose, zinc is not plutonium, it's an essential nutrient. The MDR for zinc is 15 mg, and it is fairly common to take 100 mg per day to ward off colds and flu. Farm animals eat and drink out of galvanized troughs all the time; and in rural parts of the world people still collect rainwater from galvanized roofs for their drinking water supply.

It will take years for all of the galvanizing to dissolve into the soil, probably decades more for all for much of it to be taken up into the plants; then much of the plant will be thrown away or composted and only a fraction eaten. I doubt that the vegetables have the slightest chance of providing your MDR let alone deterring colds.

The term "heavy metals" was invented by alarmists, and is a horrible one and obfuscatory -- it can be dangerous to toss that term around because it implies a commonality between relatively harmless "heavy metals" like tin, iron, gold and zinc on the one hand with extremely hazardous metals like cadmium, lead, and mercury on the other.

Regards,

A. Hi, David. Fruit juices are the kind of acidic food that concern us with galvanizing. I don't think your life is in peril, but the taste of your juice probably is. Yes, line it.

Regards,

A. Hi, Ann. I am very sorry to hear of your ill health. It sounds like you believe that your health issues are the result of exposure to something in your work environment and can be accordingly treated, whereas your doctors, who know better than you and I, apparently think your work history has little bearing on the best treatment regimen.

You could try calling a poison control center and see if they have a recommendation for a doctor you can see. A personal injury lawyer may have a specialist doctor they can refer you to who might be familiar with similar symptoms, or might be able to help you in other ways. Best of luck. I'm not making such an assertion, but it is possible that your medical issues may have nothing whatsoever to do with your employment.

Regards,

A. Hi, Richard.

In my house the same type of enclosure was also made of galvanized and was not a problem. But I understand that people can have extreme sensitivities. Please look at the exhaust ductwork on your other gas appliances like furnace, hot water heater, and clothes dryer though. Odds are all of it is galvanized.

In my house a real issue was the impossibility of cleaning out the accumulating creosote collecting on this galvanized "shelf", and you might want to make sure that you and the installer have considered the possible chimney fire danger of the installation if it allows creosote to build up.

Regards,

A. Hi, Chester. Assuming that you never smoked, you could be right that you've identified the problem. But if you do or ever did smoke, you are possibly in denial of your personal responsibility :-)

I smoked but never welded, and I, too, must take an inhaler from now on. :-(

Regards,

A. Hi, Linda.

Employers must comply with OSHA standards; it is not optional. Someone can call the OSHA hotline semi-anonymously and have the situation investigated.

However, as much as you may be concerned for your husband's health, it is he -- or better yet his sick co-workers -- who must call, not you. You have nothing to go on but second-hand hearsay about conditions in the plant, and third-hand hearsay about the health of your husband's co-workers. Good luck.

Regards,

A. Hi, Cliff.

A baby aspirin a day can be good for you or at least harmless, a baby eating a bottle of aspirin can be very bad for it.

Zinc is an essential nutrient, not a poison. The tiny amount, if any at all, of vaporized zinc from your dutch oven is surely harmless, but the clouds of vaporized zinc to which a welder is exposed when welding galvanized metal can be harmful.

Regards,

A. Hi, Anamika and friends. Galvanized metal should not be used for food. Excessive zinc can dissolve into acidic or highly alkaline foods. Plus the galvanized coating might also contain a small amount of lead, and possibly a very thin layer of toxic hexavalent chrome. It's not so much a question of actually dangerous as learning that there are safety codes which govern our design work.

Regards,

A. Hi, Usher.

I haven't personally read of sleep apnea being a symptom of exposure to zinc. Maybe the undertaker will tell your wife different though, since apparently you are not going to go to the doctor even though you stop breathing :-(

Regards,

A. Hi, Tiffanie.

I don't know whether you really mean "galvanized", i.e., coated with zinc by hot dipping -- but this is certainly not a proper material for ear wires or anything that goes in a piercing. I doubt that polishing it can possibly harm you, but inserting galvanized material into a piercing is not good for the buyer of the jewelry.

Regards,

I'm not sure what method was used to galvanize the steel wire. I do know it's smooth, and shiny, and I have been wearing a pair of earrings made out of this wire for a few days now, and my ears are fine.

Hi again.

I suspect that the wire is perhaps not galvanized, but rather coated or plated with something else, or maybe it's stainless steel. When you buy it, is there any description or specification of what it is? If it is actually galvanized it is not considered safe for skin contact whether you've had a reaction or not. Galvanized wire may also have a small amount of hexavalent chrome on it.

Regards,

A. Hi, Arthur.

As far as I know, the thickness of the steel has no effect on the melting point of the zinc coating, which is about 420 °C as mentioned earlier in the thread. Good luck.

Regards,

A. Hi Penelope. Chrome is also an essential nutrient, and miniscule amounts of hexavalent chrome probably won't survive their trip to either your vegetables or the water table.

Sorry, I never heard this story about frogs avoiding galvanized steel, but I have heard that zinc is poisonous to parrots and even to dogs, so I suppose it's possible. Although people are animals, animals are not people; the assumption that what is safe/dangerous for various animals is safe/dangerous for us and vice-versa is not always true.

Regards,

A. Hi Douglas. We're only approximating that the fence caps are "galvanized", without any detailed understanding of the manufacturing process for those specific parts.

The general rule, of course, is that nothing should be used in food preparation that was not intended for use in food preparation because no epidemiologist will have studied the issue and be able to offer any statistical data or facts. So it ends up with people just taking a guess, and their guesses are colored by their limited life experiences and their personality :-(

My own personal feeling is that I would run the BBQ for a while with the top open, and then not worry about it. But if someone else would worry about it, I really can't say they shouldn't. Sorry, but better answers are not available when we use things for unintended purposes.

Regards,

A. Hi John.

Sorry, but I just don't have any idea what that coating was. Anything you inhale is bad for you because it can coat the lungs. Phosphates and black oxides are usually waxed or oiled, so it may have been vaporized oil. I have heard (not familiar with the actual cases, but have no trouble believing it) that people have died from breathing regular compressed air because the oil dispersed in the air coated their lungs. Your smoker will probably be okay after what is on it burns off, but as I previously said, it's dangerous to use stuff on hand and assume it will be safe because, although odds are in your favor, we just don't know what it is.

Although I'm certainly no doctor, I think that one-time exposure to stuff that didn't seriously injure you rarely has any long term consequences. Good luck.

Regards,

A. Hi Cheryl. With no disrespect, I don't think that's quite the right question. I think the question should be whether galvanized steel is a good finish for jewelry, and I think the answer is "probably not".

Although galvanizing protects the steel from rusting, think about what protects the galvanizing itself from quickly dissolving away in unsightly fashion: a hard, glassy, and corrosion-resistant zinc carbonate skin forms on galvanizing when it is out in the open air and free to react with carbon dioxide. When those conditions don't exist, galvanizing corrodes away with voluminous white corrosion products called "wet storage stain", so I doubt that you will find galvanizing to be a satisfactory jewelry finish.

Regards,

A. Hi Mike. I don't think there is any cause for concern at all, except for the fact that aluminized steel may be more corrosion resistant in this particular application (I don't know).

Regards,

A. To the comments about drinking milk... It's when working with lead, like lead based paints, that when you drink a pint of milk, it stabilizes the lead toxins. I'm not sure if it's the same for galvanized metals.

A. Hi Jens. You'll be happier if you paint a piece of black iron pipe instead. The paint will stick better; you'll worry less (we've explained again & again that it's all is a matter of degree, and nobody can help you decide what the risk is and whether you'll accept it); and galvanized pipe isn't ideal for this wear and type of environment. Good luck.

Regards,

A. Hi Kate. Things are not "safe" vs. "unsafe" -- rather, everything is relative. Far more children die in car accidents than from any other cause, but few parents keep their children out of cars because they are "unsafe".

9 month old children should not be sucking on galvanized objects -- but that does not mean that galvanized buckets for storage is any realistic threat at all to older children. Best of luck.

Regards,

A. Hi Roger. You posted your question under the topic of safety of "zinc" (galvanizing), but you say the heating plate is made of "tin", but it looks like "chrome". Unfortunately, you don't actually know what it's made of, and it's unlikely that any reader would either, unless they happen to be retired from a career working in the plating shop of Broil King :-)

You say this item is vintage, so presumably it's been used many times over the decades. I don't know how a thin shiny plating on the surface of a heating plate could possibly sustain outgassing for decades even if it were made of some exotic poisonous metal, which it's obviously not. Don't worry about it! But if you want something to worry about, consider whether there might be asbestos in the insulation :-)

Good luck.

Regards,

A. Hi Jaime. It was a livestock water container, so it was safe enough for that; and he's barely warming it, so I see no problem.

Regards,

A. Hi Brandon. As mentioned a couple of times, zinc is an essential nutrient not a toxin. The amount of this essential nutrient that you have added to a pool full of swimming water by heating the galvanized pipe is probably not even measurable. Good luck.

Regards,

A. Hi. Personally I wouldn't give it a second thought if you're not welding it.

Regards,

A. Hi Elizabeth. Galvanizing might have some small amount of lead in it, it might have a small amount of leachable nickel in it, it might have a very dilute chromate conversion coating on it. I don't think it's particularly hazardous, but the operative idea is that if you re-purpose something, using it for something it wasn't intended for, you have no assurance of its safety for the new application. The designer might not know or remember that people might hang the item on a wall for kids to play with.

If you paint it then it sounds quite safe, but paint doesn't stick well to galvanizing. You'd probably have to start with a primer designed for galvanized surfaces before applying your decorative spray paint. Good luck.

Regards,

A. Hi Dan. Galvanizing often has a final quench in hexavalent chromate. Even though the amount is miniscule, as a matter of principle I would not use metal that has even a miniscule amount of carcinogenic hexavalent chrome on it as jewelry. Probably just as important, galvanized steel won't make for an aesthetically pleasing jewelry item because of its propensity towards white rust and corrosion when exposed to water and sweat.

Regards,

A. Have to agree with Ted, even though I sell galvanizing.

It's primarily corrosion protection for steel. It's a zinc coating on the steel that slowly erodes in preference to the steel, until all consumed after which the steel starts to rust (perhaps decades later).

It's not for wearing, eating, etc.

A. Hi Ryan. Please contact your town or county health department about this. Galvanized pipe was very widely used for water service in the old days but is rarely used today. It may be against local codes. Plastic pipe is probably more common today.

Regards,

A. Hi Carlos. If you're not getting that backsplash hot enough that you're worried about burning the house down, I don't think there is any cause for concern. Again, zinc is not a poison, it's an essential micro-nutrient; the problem comes from overdoses that welders encounter when vaporizing the zinc into clouds of zinc-based smoke.

Regards,

A. Hi. Lots of things that get hot are galvanized. Exhaust ducts for furnaces and water heaters, internal parts of gas and charcoal grills, ashpans in airtight stoves, etc. Outdoor burning, which is nowhere near welding temperatures, and where the smoke getting to your lungs and eyes will force you upwind anyway, doesn't sound to me like it poses any issue at all.

Regards,

A. Hi. No problem. And they're probably clear coated after the zinc plating anyway. Of course, China and India are not crawling with lawyers and EPA people like the USA -- so just because it says zinc covered steel doesn't necessarily mean it is.

Regards,

A. Hi Brian. I think people misunderstand the nature of the "zinc fumes" issue. Zinc is an essential micronutrient, not a toxin. It's a problem for welders because of the blinding heat of electric welding vaporizing the zinc, combined with the fact that a welder tends to do a lot of welding, not one little spot weld a month. And I strongly doubt that the zinc coating will even melt, let alone vaporize.

Products very similar to hardware cloth, but woven from stainless steel, are available if you prefer.

Regards,

A. Hi. Zinc is an essential nutrient, not a toxin, but it doesn't sound like any detectable amount could end up in your food anyway.

Regards,