
Things I Won’t Touch: Hydrofluoric Acid (2004) - networked
http://blogs.sciencemag.org/pipeline/archives/2004/03/03/things_i_wont_touch_1
======
j_m_b
As a chemist, my most horrifying compound is Dimethylmercury. It readily
passes through protective latex and PVC. Consider Karen Wetterhahn. She
spilled a couple of drops onto her gloves, quickly cleaned it up but still
ended up dying a rather gruesome death where she persisted for weeks in a
state that shifted from comatose to highly agitated before she passed. This
was preceded by nearly a year of abdominal pain, weight loss and mental
decline. Just a little bit will kill you in a slow, agonizing death and your
gloves won't even save you!

~~~
chucksmash
New England Journal of Medicine write up of this case:

[http://www.nejm.org/doi/full/10.1056/NEJM199806043382305](http://www.nejm.org/doi/full/10.1056/NEJM199806043382305)

~~~
monochromatic
Good write up, I'd only read the wikipedia summary. That stuff is terrifying.

~~~
Gibbon1
What's weird is the metal and inorganic salts of mercury aren't particularly
toxic.

The vapor is toxic, one of my college professors said his graduate adviser was
suffering from years of exposure to mercury fumes because in the bad old days
they used to seal the gas valves in the lab with a little pool of mercury.
Poor guy spent 40 years in the lab breathing mercury fumes.

~~~
LeifCarrotson
If you can spend 40 years in a lab breathing mercury fumes, maybe it isn't as
dangerous as the public perceives it to be? I mean sure, let's stop sealing
gas valves with it, a space should be built to be safe to work in for 40
years. But let's not freak out about perorming a couple experiments with it,
using a mercury-bulb switch in a thermostat, or the few milliliters released
by a broken CFL bulb.

~~~
mixmastamyk
Mercury is all-natural after all.

------
cstross
This puts me in mind of one of my favourite cringe-worthy medical paper
abstracts: "Fulminant acute colitis following a self-administered hydrofluoric
acid enema" (Am J Gastroenterol. 1993 Jan;88(1):122-6):

[http://www.ncbi.nlm.nih.gov/pubmed/8420252](http://www.ncbi.nlm.nih.gov/pubmed/8420252)

The phrase "while intoxicated from intranasal cocaine administration" made it
into the abstract. One suspects the words "watch this!" were uttered in the
immediately preceding moments ...

~~~
shiro
There was a tragic accident in Japan back in 1982: A dentist mistakenly
applied HF solution instead of fluorides to a girl, who subsequently suffered
extreme pain and died. Both materials are called フッ素 (fusso, which is actually
the name of Fluorine), and there was a fatal miscommunication between
dentist's assistant and the distributor. The dentist felt so guilty and
stressed out that he died from stroke at the girl's funeral.

For Japanese in my generation, the fear of HF was imprinted by the accident. I
couldn't find English reference, but here's Japanese wikipedia page:

[https://ja.wikipedia.org/wiki/%E5%85%AB%E7%8E%8B%E5%AD%90%E5...](https://ja.wikipedia.org/wiki/%E5%85%AB%E7%8E%8B%E5%AD%90%E5%B8%82%E6%AD%AF%E7%A7%91%E5%8C%BB%E5%B8%AB%E3%83%95%E3%83%83%E5%8C%96%E6%B0%B4%E7%B4%A0%E9%85%B8%E8%AA%A4%E5%A1%97%E5%B8%83%E4%BA%8B%E6%95%85)

~~~
shiro
Correction: After some more searching, it turned out the doctor did collapsed
at the funeral from stroke but survived.

------
js2
My favorite of his is "Sand Won't Save You This Time", about chlorine
trifluoride, "a stronger oxidizing agent than oxygen itself":

[http://blogs.sciencemag.org/pipeline/archives/2008/02/26/san...](http://blogs.sciencemag.org/pipeline/archives/2008/02/26/sand_wont_save_you_this_time)

which links to this PDF:
[http://web.archive.org/web/20060318221608/http://www.airprod...](http://web.archive.org/web/20060318221608/http://www.airproducts.com/nr/rdonlyres/8479ed55-2170-4651-a3d4-223b2957a9f3/0/safetygram39.pdf)

Video of it reacting:
[https://www.youtube.com/watch?v=M4l56AfUTnQ](https://www.youtube.com/watch?v=M4l56AfUTnQ)

Another article: [http://www.todayifoundout.com/index.php/2015/07/chlorine-
tri...](http://www.todayifoundout.com/index.php/2015/07/chlorine-trifluoride-
aka-chemical-can-set-fire-glass/)

~~~
smaddox
You just sent me on a long detour searching for the book he references:
"Ignition!: An informal history of liquid rocket propellants" by John D Clark

For any other people interested, it's out of print, but a PDF is available
here:
[http://library.sciencemadness.org/library/books/ignition.pdf](http://library.sciencemadness.org/library/books/ignition.pdf)

~~~
hyperion2010
Ignition is an absolutely wonderful book, I send it to everyone I meet who
thinks they want to be a scientist. It is also absolutely hilarious.

~~~
pjc50
It's fantastic, an alternating mix of dry chemistry and hair-raising lab
anecdotes.

For those who haven't read it: in the post-war early rocket period, government
chemists could tell from basic stochiochemistry what mixtures might make good
rocket fuels. But their _other_ properties had to be tested experimentally.
Especially hypergolicity and detonation resistance. There's a long subthread
about red fuming nitric acid, which would make a great oxidiser once people
could find a way of stopping it eating through stainless steel tanks.

------
pdkl95
My mother has a story - and some significant scars to back it up, about her
time employed in the 70's at Litronix moving wafers from between the stepper,
furnace, etching, etc in the era where you could still be in the same room as
the wafer.

As this was the 70s, "occupational safety" didn't mean the same thing as it
does today, so apparently the etching was done _by hand_. This involved
putting on three layers of heavy gloves and dipping boats of wafers in some
type of etching acid. My mother wasn't sure of the contents, but knew it
involved extremely concentrated acids, which were shipped in daily because the
couldn't be stored more than a few days in the glass bottles (!!!). As she
described it, the HCl and HNO3 were easy to identify when you worked with
them, because they cause intense burning - and scaring - if you splashed any
on your arm.

At least one of the etching steps, though (maybe all? I'm not sure) used
concentrated HF.

So this went fine, until my mother took off her gloves one day... and aw bone.
Didn't even notice it. She sat with her hand under the DI faucet suggesting
someone should probably call an ambulance. The paramedics wanted to amputate
her hand immediate (on site). Instead, they were talked into trying to
estimate how much acid actually actually made it's way to her hand, and spent
the afternoon injecting various things to try to neutralize the HF.

Fortunately, it must have been a very small amount of acid, as she made a full
recovery, albeit with a nasty scar on her finger. It wasn't even the worst
thing that happened to her - she was a _lot_ more concerned the day she
discovered someone had used several full storage shelves (total an entire wall
wide, floor to ceiling) to store the "empty" nitric acid bottles that were
still full of very-nasty fumes. Shelves, that were a few feet from the (full)
liquid O2 tanks. That warranted an immediate call to OSHA... from another
building.

The industry is a _lot_ safer than it once was.

------
OopsCriticality
Speaking with my chemist's hat on… _wimp_.

Seriously, there are any number of nasty things floating around a wet
chemistry lab. Chromerge and piranha solutions (sometimes _aqua regia_ ) for
cleaning glassware, various super acids and bases, pyrophoric organometallics,
stuff that's oxygen or water or shock sensitive… the list goes on. HF is
certainly bad, but it tends to get the respect it deserves and so is handled
safely. I'm more worried about chronic occupational exposure to "safer" things
like chloroform.

Edit: the one that really scares me? Anything solvated with DMSO. It
dramatically increases absorption through the skin. I bet every chemist has a
secret chemical fear.

Edit 2: oh, and peroxides. One idiot postdoc had a habit of buying THF without
stabilizers (no need for him to do so), and storing them in the back of the
chemicals cabinet where they were frequently forgotten. At least he had the
decency to store them on the bottom shelf. So admittedly I have two fears, but
I'll work with HF!

~~~
AceJohnny2
> Edit 2: oh, and peroxides.

Then you might be amused by his post about _peroxide_ peroxides (just add more
-O- links in the HOOH chain)

[http://blogs.sciencemag.org/pipeline/archives/2014/10/10/thi...](http://blogs.sciencemag.org/pipeline/archives/2014/10/10/things_i_wont_work_with_peroxide_peroxides)

~~~
pixl97
Did someone say FOOF?!

[https://en.wikipedia.org/wiki/Dioxygen_difluoride](https://en.wikipedia.org/wiki/Dioxygen_difluoride)

~~~
AceJohnny2
Derek said FOOF!

[http://blogs.sciencemag.org/pipeline/archives/2010/02/23/thi...](http://blogs.sciencemag.org/pipeline/archives/2010/02/23/things_i_wont_work_with_dioxygen_difluoride)

------
kens
The history of isolating fluorine from HF is pretty scary:

Humphry Davy of England: poisoned, recovered. George and Thomas Knox of
Ireland: both poisoned, one bedridden 3 years, recovered. P. Louyet of
Belgium: poisoned, died. Jerome Nickels of Nancy, France: poisoned, died.
George Gore of England: fluorine / hydrogen explosion, narrowly escaped
injury. Henri Moissan of France: poisoned several times, success, but
shortened life. For isolating fluorine, Moissan got the Nobel prize, two
months before he died.

Source:
[https://en.wikipedia.org/wiki/History_of_fluorine#Early_isol...](https://en.wikipedia.org/wiki/History_of_fluorine#Early_isolation_attempts)

~~~
scarmig
Moissan died of appendicitis iirc. Is Fl associated with it?

------
spchampion2
Related: "Things I Won't Work With: Dioxygen Difluoride"

[http://blogs.sciencemag.org/pipeline/archives/2010/02/23/thi...](http://blogs.sciencemag.org/pipeline/archives/2010/02/23/things_i_wont_work_with_dioxygen_difluoride)

~~~
twic
I think the best one in this series is chlorine trifluoride [1]:

> The compound also a stronger oxidizing agent than oxygen itself, which also
> puts it into rare territory. That means that it can potentially go on to
> “burn” things that you would normally consider already burnt to hell and
> gone, and a practical consequence of that is that it’ll start roaring
> reactions with things like bricks and asbestos tile.

[1]
[http://blogs.sciencemag.org/pipeline/archives/2008/02/26/san...](http://blogs.sciencemag.org/pipeline/archives/2008/02/26/sand_wont_save_you_this_time)

------
dnautics
I'm the opposite of Lowe. I would never touch HF solutions, and am totally OK
with HF gas (and I have used HF gas). HF solutions are a weak base - which
means that quite a bit of it remains as the diatomic molecule HF, which can
penetrate cell membranes and wreak havoc in your body. You can get severely
injured without noticing it. If there's any risk of exposure, you need to rub
yourself with calcium gluconate cream, ASAP.

HF gas, on the other hand, well, it's dangerous enough that you're going to be
taking a ton of precautions around it. Your setup is going to be under
negative pressure, and in a fume hood. You're going to wear thick rubber
splashguard over your lab coat, you're going to have a checklist of things to
do in the procedure, the entire apparatus is teflon, and there's a calcium
hydroxide scrubber out the other end, and you'll never work with more than 10
mL at a time.

Lowe's account of a leak is a little bit overwrought. Unless you're working in
an (idiotic, but I've seen them) positive pressure setup, the best thing to do
is to calmly shut the valve to the HF tank, close the fume hood, and walk
away.

~~~
semi-extrinsic
> If there's any risk of exposure, you need to rub yourself with calcium
> gluconate cream, ASAP.

One of the really nasty parts is that an HF solution will penetrate your
fingernails, while calcium gluconate will not. You won't like the solution to
that problem.

------
jjoonathan
I've heard a suspiciously large number of explanations for HF's toxicity.

1\. It eats your bones (BS meter at 99.9% due to stoichiometry)

2\. It poisons enzymes (as seen in TFA, passes the BS detector, but begs the
question: which ones?). EDIT: "which ones?" answered by [2], but it's focus is
on cell biology not toxicology, so it's possibly answering the question "what
causes the local burns?" rather than "what kills you dead?".

3\. It binds Ca++ in your blood, stopping the power stroke of your heart [1]
(my own suspicion, although it's obvious enough that there is a 0% chance of
it being "original"). EDIT: [3] pretty much confirms this.

I've lost convenient access to the academic literature, so if there's anyone
on here who would be willing to do a quick (ha) dive on my behalf, I'd be much
obliged. EDIT: I think I found the answers I wanted, but most of the top
results were paywalled, so I'd still appreciate a second look by someone with
access to institutional subscriptions.

[1]
[https://cnx.org/resources/cee66a1bf085ebac300c9c15805098f254...](https://cnx.org/resources/cee66a1bf085ebac300c9c15805098f254299df0/2026_Action_Potential_Heart_Contraction.jpg)

[2]
[http://www.researchgate.net/profile/Luz_Maria_Del_Razo/publi...](http://www.researchgate.net/profile/Luz_Maria_Del_Razo/publication/45281342_Molecular_mechanisms_of_fluoride_toxicity/links/09e415101a1cc46320000000.pdf)

[3]
[http://www.atsdr.cdc.gov/mhmi/mmg11.pdf](http://www.atsdr.cdc.gov/mhmi/mmg11.pdf)

~~~
OopsCriticality
In safety training at a university, we were instructed that if we were exposed
to aqueous HF, we were to immediately slather on calcium gluconate on the burn
area, grab an HF MSDS, and demand that the ambulance take us to a specific
Level 1 trauma center and insist that the physicians understand that we were
exposed to HF and not some generic acid.

I don't know the precise mechanism for toxicity (I thought it was
hypocalcemia), but if the tradionally safety-lax academia takes HF that
seriously, you know it's the real deal.

~~~
jjoonathan
Yep, I got the same lecture, I was specifically asking about mechanism because
the explanation we were given was "eats your bones" which is patently
ridiculous.

~~~
OopsCriticality
Your bones are constantly remodeled, as part of calcium regulation in the
body. HF, interfering with that remodeling, may give the appearance of it
"eating your bones".

~~~
jjoonathan
As a mechanism for chronic toxicity? Sure. As a mechanism for acute toxicity?
Not a chance.

The "slap on some calgonate and rush to the hospital" protocol (of which you
were quick to remind us) was justified by way of the acute toxicity (to me,
anyway), not prevention of chronic toxicity, so my remark stands.

------
Dwolb
Once upon a time I did an electrical engineering internship on-site at an oil
refinery. Part of my training was to learn about chemicals like HF and how
dangerous they were to human life and what to do if exposed.

Then I learned about how basically in large oil refineries pipes are leaking
all the time and crews are always coming in to fix the leaks in the pipes (but
not often repair). I left that industry pretty quick and never looked back.

------
tgflynn
Note that he's primarily taking about HF gas, not the aqueous solution.
Aqueous hydrofluoric acid is certainly not to be trifled with but I don't
think it's in quite the same category as some of the other substances this guy
talks about. I used to work in a lab that used large quantities of the stuff
and I knew someone who got some on his skin. He went to the hospital but I
don't think he suffered any lasting consequences.

------
vilhelm_s
The current HN title is bad, since the first paragraph says that he will
happily work with "hydroflouric acid", but not with "hydrogen flouride" (i.e.
gaseous HF).

------
thingsgoby
if you like that article you'll love this video "5 of Worlds most dangerous
Chemicals"
[https://www.youtube.com/watch?v=ckSoDW2-wrc](https://www.youtube.com/watch?v=ckSoDW2-wrc)

------
rdl
It seems stupid to have humans anywhere near this stuff. Robot chemistry labs
would make a lot of sense -- doing the same operations over and over, exactly
the same way, with limited downside when things go wrong.

I know some of the biochem procedures are moving to "cloud labs" \-- using
inherently small amounts of chemicals and repeating things many times. Doing
similar things in larger scale labs also seems worth it.

------
codemonkeymike
I had a professor who worked in a Dupont lab in New Jersey. He studied crystal
structures using x-rays, something too cool for me to comprehend. Anyway he
said the lab did work with a mixture of acids they called "Liquid Fire". It
would pretty much corrode through any container, metal/plastic/glass. He said
there were talks to sell it to the military but it would have been too unsafe
to get to the battle field. Note didn't read the article, I think I have read
this one before.

------
wycx
[http://www.ab.ust.hk/hseo/tips/ch/ch005.htm](http://www.ab.ust.hk/hseo/tips/ch/ch005.htm)

A fatality from a small <250 mL spill of HF solution.

------
cafard
I think that one of my father's USGS friends inadvertently got himself with
some while using a pipette. It must have been thoroughly unpleasant, but the
guy was alive and kicking 20 years later.

------
mrfusion
Everyone knows this from breaking bad right?

