# Are Hydroflouric acid burns invariably fatal, I once saw an ER episode... **URL:** \ **Category:** Factual Questions\ **Created:** [April 26, 2004, 7:56am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064 "2004-04-26T07:56:26Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Roland\_Deschain](https://avatars.discourse-cdn.com/v4/letter/r/73ab20/32.png) [@Roland\_Deschain](https://boards.straightdope.com/u/Roland_Deschain)\ **Post date:** [April 26, 2004, 7:56am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/1 "2004-04-26T07:56:26Z")
where a guy goes to the ER with what he considers to be a relatively minor acid burn. After some research the doctors tell him that in fact he’s got less than a day to live because the Hydroflouric acid will catalyze a crystal reaction within his body that utlmately kills him (if I remember correctly it may have been hypo or hyper kalemia that did him in). There was no effective treatment and the guy got progressively worse and died. Is this just Hollywood fantasy? Can what seems like a relatively small acid burn leave you feeling okay initially, but then dead just a day later? This is especially fascinating given that HF is a weak acid! ---
**Author:** ![EvilGhandi](https://avatars.discourse-cdn.com/v4/letter/e/f17d59/32.png) [@EvilGhandi](https://boards.straightdope.com/u/EvilGhandi)\ **Post date:** [April 26, 2004, 8:18am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/2 "2004-04-26T08:18:03Z")
Yes. Hydrogen flouride is deadly to humans in any amount. Thats why the CIA coats its tinfoil beanies in it. I hope this is helpfull. ---
**Author:** ![robotic\_panda](https://avatars.discourse-cdn.com/v4/letter/r/ed8c4c/32.png) [@robotic\_panda](https://boards.straightdope.com/u/robotic_panda)\ **Post date:** [April 26, 2004, 9:36am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/3 "2004-04-26T09:36:51Z")
Purely anecdotal, I know, but a friend of mine works with industrial chemicals; he told me basically the same thing. It can be deadly because the symptoms can take a while to appear, and by then it can be too late. Now for a [cite](http://www.emedicine.com/emerg/topic804.htm): > [@](#): > > The 2 mechanisms that cause tissue damage are corrosive burn from the free hydrogen ions and chemical burn from tissue penetration of the fluoride ions. > > Fluoride ions penetrate and form insoluble salts with calcium and magnesium. Soluble salts also are formed with other cations but dissociate rapidly. Consequently, fluoride ions release, and further tissue destruction occurs. And: > [@](#): > > Systemic fluoride ion poisoning from severe burns is associated with hypocalcemia, hyperkalemia, hypomagnesemia, and sudden death. So yes, its some dangerous stuff, even in small concentrations. ---
**Author:** ![curly\_chick](https://avatars.discourse-cdn.com/v4/letter/c/7ba0ec/32.png) [@curly\_chick](https://boards.straightdope.com/u/curly_chick)\ **Post date:** [April 26, 2004, 9:53am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/4 "2004-04-26T09:53:38Z")
I used to work with it and it was one of the very few chemicals which ever gave me the heebie jeebies. Anyone who uses it should know to have a tube of the antidote gel within easy reach. The antidote is only useful, though, if you apply it straight away as it causes the fluoride to precipitate out before it gets into your skin and attacks the muscles, bones and connective tissue. ---
**Author:** ![Roland\_Deschain](https://avatars.discourse-cdn.com/v4/letter/r/73ab20/32.png) [@Roland\_Deschain](https://boards.straightdope.com/u/Roland_Deschain)\ **Post date:** [April 26, 2004, 10:06am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/5 "2004-04-26T10:06:12Z")
the stuff. What were they thinking? Lab, was crazy and it was not uncommon to have spills, ect. Seems like this should be reserved for highly controlled environments. ---
**Author:** ![scm1001](https://avatars.discourse-cdn.com/v4/letter/s/c4cdca/32.png) [@scm1001](https://boards.straightdope.com/u/scm1001)\ **Post date:** [April 26, 2004, 10:23am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/6 "2004-04-26T10:23:12Z")
here are some case studies from [http://ehs.unc.edu/pdf/HydrofluoricAcid.pdf](http://ehs.unc.edu/pdf/HydrofluoricAcid.pdf) (pdf file). Fluoride is probably as toxic as cyanide, though evidence is mixed A dermal exposure to 70 percent hydrofluoric acid over a 2.5 percent total body surface area resulted in death. The serum calcium level was 2.2 milligrams/deciliter. ������ An adult patient who developed 25 percent total body surface area second degree burns after exposure to a 70 percent hydrofluoric acid preparation died in cardiac arrest. Ionized serum calcium level was 1.7 milligrams per deciliter (normal: 4 to 4.8) immediately premortem. ������ Two workers died following a splash exposure of 70 percent hydrofluoric acid to the face, chest, arms and legs. Both workers were promptly removed from site of exposure. Clothing was removed and burns were initially treated at the workplace with a cold shower and alcohol was applied to burn areas. Suitable protective clothing was not worn at the workplace. ������ A woman died from severe chemical burns of the skin and lungs, with intense pulmonary hemorrhagic edema after having acid thrown onto her face during an attack. ������ A patient with HF burns involving 8 percent of his body died from intractable cardiac arrhythmia secondary to the depletion of ionized calcium. ---
**Author:** ![robotic\_panda](https://avatars.discourse-cdn.com/v4/letter/r/ed8c4c/32.png) [@robotic\_panda](https://boards.straightdope.com/u/robotic_panda)\ **Post date:** [April 26, 2004, 10:26am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/7 "2004-04-26T10:26:55Z")
> [@Roland Deschain](#): > > the stuff. What were they thinking? Lab, was crazy and it was not uncommon to have spills, ect. Seems like this should be reserved for highly controlled environments. Hmmmm… are you sure you were using hydro **fluoric** acid? ---
**Author:** ![Roland\_Deschain](https://avatars.discourse-cdn.com/v4/letter/r/73ab20/32.png) [@Roland\_Deschain](https://boards.straightdope.com/u/Roland_Deschain)\ **Post date:** [April 26, 2004, 10:51am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/8 "2004-04-26T10:51:49Z")
was a raving maniac (which I may be, but that is a different point entirely). It was only on a couple of occasions, and was accompanied by stern warning, but still why take the chance? ---
**Author:** ![robotic\_panda](https://avatars.discourse-cdn.com/v4/letter/r/ed8c4c/32.png) [@robotic\_panda](https://boards.straightdope.com/u/robotic_panda)\ **Post date:** [April 26, 2004, 11:05am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/9 "2004-04-26T11:05:47Z")
No kidding! From [http://www.ehs.neu.edu/hf.htm](http://www.ehs.neu.edu/hf.htm) a list of precautions: > [@](#): > > IV. Safe Workplace Practices: > Ensure that HF is handled by highly trained, adequately protected and responsible personnel. > All work with HF must be done in a fume hood. > If HF is used in experiments done outside the fume hood, adequate ventilation must be present to ensure that the HF atmospheric concentration does not exceed permissible limits. > Individuals working with HF must wear personal protective equipment made of materials such as polyvinyl chloride (PVC) or chlorobutadiene (Neoprene). Note: PVC material degrades in presence of HF so inspect the gloves and apron made out of this material and replace before they break. > Laboratory attire must include: a face shield (or safety glasses), Neoprene gloves, apron or lab coat. > The safety shower and eye wash must be located near the area where HF is being used. > Keep calcium gluconate gel and drops handy in case of an emergency. > HF should be stored away from incompatible chemical and materials. Corrosive action of HF on metals can result in the formation of hydrogen in containers and piping to create fire and explosion hazards, so potential sources of ignitio n should be excluded from the areas where HF is used and stored. > Use minimum quantities of HF and where possible, use a less dangerous substitute. > Make sure more than one person is present during HF usage. Now that sounds like something I wouldn’t be too eager to play around with. If people who have to work with it get the “heebie-jeebies” I can’t imagine having to do school lab experiments with it. Give me a C and I’ll write a report on it. Then again, i’m a wimp (with a fear of deadly chemical burns). YMMV ---
**Author:** ![sunfish](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@sunfish](https://boards.straightdope.com/u/sunfish)\ **Post date:** [April 26, 2004, 11:07am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/10 "2004-04-26T11:07:40Z")
Hydro **chloric** acid is quite commonly used in college chem lab experiments. Hydro **fluoric** acid is a completely different animal - it is most certainly NOT a weak acid! I’d be willing to bet everything I own that there is no way you used HF in a regular chem lab because of the dangers involved. I’m not joking. I occasionally use a 48-51% HF solution to etch certain kinds of rock chips to prepare them for viewing under a scanning electron microscope (SEM), and frankly the whole process makes me sweat a little until it’s finished. Proper use of HF requires an appropriate fume hood (one capable of handling the corrosive fumes that HF generates), teflon beakers and forceps (because HF will eat through glass), safety goggles and special chemical-resistant gloves and lab clothing. A couple of items that will help illustrate the danger more clearly (note: PDF files): [Material Safety Data Sheet for 49% Hydrofluoric Acid](http://hracid.com/pdf/hfaq49.pdf) [Recommended Medical Treatment for Hydrofluoric Acid Exposure](http://specchem-apps.alliedsignal.com/prodcat/Pdfs/FLO/Other1/hfmedbook.pdf) Bottom line is - yes, the scenario described in _ER_ is quite possible. ---
**Author:** ![robotic\_panda](https://avatars.discourse-cdn.com/v4/letter/r/ed8c4c/32.png) [@robotic\_panda](https://boards.straightdope.com/u/robotic_panda)\ **Post date:** [April 26, 2004, 11:13am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/11 "2004-04-26T11:13:52Z")
> [@sunfish](#): > > Hydro **chloric** acid is quite commonly used in college chem lab experiments. Hydro **fluoric** acid is a completely different animal - it is most certainly NOT a weak acid! I’d be willing to bet everything I own that there is no way you used HF in a regular chem lab because of the dangers involved. I’m not joking. Exactly **sunfish** , thats what I was thinking… weak acid, and hydrochloric sounds a lot like hydrofluoric. I don’t think they’d let college kids loose with hydrofluoric acid… ---
**Author:** ![Roland\_Deschain](https://avatars.discourse-cdn.com/v4/letter/r/73ab20/32.png) [@Roland\_Deschain](https://boards.straightdope.com/u/Roland_Deschain)\ **Post date:** [April 26, 2004, 11:14am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/12 "2004-04-26T11:14:05Z")
I can’t vouch for the strength of the acid we used (I think it was rather dilute). Also, I am confident that HF was one of the **weak** acids that we had to memorize. Keep in mind that acid strength is defined by it’s disassociation constant rather than it’s effects upon the human body. With HF the real danger isn’t the superficial chemical burns, but rather the systemic, subsequent reactions within the body that occur. Indeed, the “weakness” of HF may contribute to its lethality in that someone may not realize the seriousness of the injury and seek help in time (it may also play a part in it’s ability to penetrate tissue, but now I speculating). ---
**Author:** ![robotic\_panda](https://avatars.discourse-cdn.com/v4/letter/r/ed8c4c/32.png) [@robotic\_panda](https://boards.straightdope.com/u/robotic_panda)\ **Post date:** [April 26, 2004, 11:23am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/13 "2004-04-26T11:23:48Z")
> [@Roland Deschain](#): > > I can’t vouch for the strength of the acid we used (I think it was rather dilute). Also, I am confident that HF was one of the **weak** acids that we had to memorize. Keep in mind that acid strength is defined by it’s disassociation constant rather than it’s effects upon the human body. With HF the real danger isn’t the superficial chemical burns, but rather the systemic, subsequent reactions within the body that occur. Indeed, the “weakness” of HF may contribute to its lethality in that someone may not realize the seriousness of the injury and seek help in time (it may also play a part in it’s ability to penetrate tissue, but now I speculating). As I posted in my first reply, the free hydrogen ions cause the CORROSIVE or “superficial” burns, the chemical burn is caused by flouride ions… so yes, you’re right… a low concentration does cause larger problem for that reason, the physical or superficial symptoms take longer to occur, while the chemical burn has had more time to chain-react. ---
**Author:** ![Catalyst](https://avatars.discourse-cdn.com/v4/letter/c/e47774/32.png) [@Catalyst](https://boards.straightdope.com/u/Catalyst)\ **Post date:** [April 26, 2004, 11:27am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/14 "2004-04-26T11:27:17Z")
For what it’s worth, I know that my high school Chemistry teacher worked with HF occasionally in lab, but that was doctorate level stuff and she described conditions consistent with what **robotic\_panda** describes. ---
**Author:** ![sunfish](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@sunfish](https://boards.straightdope.com/u/sunfish)\ **Post date:** [April 26, 2004, 11:33am UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/15 "2004-04-26T11:33:15Z")
Yes, HF is a weak acid w/r/t the number of hydronium ions (H[sub]3[/sub]O[sup]+[/sup]) generated when it’s dissolved into water. In terms of corrosive effects it’s not. Remember, **Roland** , that there may be plenty of people reading this post who don’t automatically know what the term “weak acid” means in a chemistry context, so it’s good to explain such terms a little when you use them. Dilute solution or not, I’m curious as to what undergrad class had you using HF in a lab, and what the experiment was. If anything, working with a very dilute solution is a very poor idea with relatively inexperienced students, as “dilute” tends to be translated internally as “not so dangerous,” a really bad thing with HF in particular since the signs of exposure are delayed that much further with a more dilute solution. You’re a nursing student, yes? I’m hard-pressed to think why you would be working with an inorganic acid of that caliber, but I’m willing to learn. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [April 26, 2004, 1:13pm UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/16 "2004-04-26T13:13:15Z")
HF burns are _not_ inevitably fatal. A guy I know who works with it regularly (and knows what he’s doing) managed to get some on him, and he’s still alive and kicking. I note that he immediately took action and got immediate help. It still required the removal of large chunks of flesh, though. Not trivial stuff to fool around with. I can’t believe that they would use this stuff for an undergraduate lab, or even a graduate lab. Most experiments can be done with some non-exotic acid (You can’t even keep HF in glass bottles – it eats through the sides. The used to have to keep it in wax-lined containers. Nowadays they keep it in plastic). If you want to etch glass, you can use ammonium bifluorite. What the hell would they have you using HF for, anyway? ---
**Author:** ![Finagle](https://avatars.discourse-cdn.com/v4/letter/f/b19c9b/32.png) [@Finagle](https://boards.straightdope.com/u/Finagle)\ **Post date:** [April 26, 2004, 1:24pm UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/17 "2004-04-26T13:24:35Z")
Hydrofluoric doesn’t always come in lethal concentrations. You can, for example, buy it as a cream for etching glass. I used to have a bottle of it around somewhere. It’s still pretty nasty stuff and you need gloves, long-sleeved shirt, and a face shield to use it safely. But it’s certainly not unreasonable to think that it might be used in a chemistry lab safely. ---
**Author:** ![robotic\_panda](https://avatars.discourse-cdn.com/v4/letter/r/ed8c4c/32.png) [@robotic\_panda](https://boards.straightdope.com/u/robotic_panda)\ **Post date:** [April 26, 2004, 1:31pm UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/18 "2004-04-26T13:31:52Z")
> [@Finagle](#): > > Hydrofluoric doesn’t always come in lethal concentrations. You can, for example, buy it as a cream for etching glass. I used to have a bottle of it around somewhere. It’s still pretty nasty stuff and you need gloves, long-sleeved shirt, and a face shield to use it safely. But it’s certainly not unreasonable to think that it might be used in a chemistry lab safely. Again, if its for school, which i’m paying for anyway, i’ll finagle (no pun intended) a C for a report on the caustic properties… gladly. ---
**Author:** ![sunfish](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@sunfish](https://boards.straightdope.com/u/sunfish)\ **Post date:** [April 26, 2004, 1:47pm UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/19 "2004-04-26T13:47:04Z")
When I took general chemistry as an undergrad, it was not uncommon for people to get drops of stuff on themselves or on their clothes. I burned a hole in my sweater once using HCl, even though I thought I was being very careful. Other jokers liked to do things like try to see whether they could remove their fingerprints. :rolleyes: Safety procedures may well have been tightened since I took those classes (early 90s), but the only thing we had then was safety goggles. As noted above, HF requires some heavy-duty protective measures. (Corrected link for HF material safety data sheet in PDF) The first couple of times I used HF, I was personally supervised every step of the way by a senior lab person, and this was AFTER taking the mandatory lab safety class required by my graduate institution. I’m having a really hard time imagining what basic chemistry principles could be illustrated only with the use of HF, as opposed to something less hazardous, especially given the propensity for undergrads to do something stupid or careless (and the level of liability assumed by the school!). ---
**Author:** ![sunfish](https://avatars.discourse-cdn.com/v4/letter/s/96bed5/32.png) [@sunfish](https://boards.straightdope.com/u/sunfish)\ **Post date:** [April 26, 2004, 1:49pm UTC](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064/20 "2004-04-26T13:49:01Z")
[HF safety data](http://hfacid.com/pdf/hfaq49.pdf) [Next page](https://boards.straightdope.com/t/are-hydroflouric-acid-burns-invariably-fatal-i-once-saw-an-er-episode/242064.md?page=2)