What is the toxic effects of mixing muriatic acid and bleach?

A. Sorry this happened to you Ashley. And sorry that you couldn't get a live response. But please don't use the internet for medical advice; that's dangerous.
You should at least call your doctor's office for yourself; and because 4 year old children are not experienced enough to fully understand and vocalize how they feel, I think taking her to the doctor is in order.
Luck & Regards,


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

A. Adding muriatic acid to a pool is common. Something is not being told. Normal-reasonable additions will not cause the problem if the acid was added to the pool water. Now if it was added to the system in a manner that got to a chlorine tablet chlorinator, you could have a significant problem. My guess is that you use chlorine gas and a gross excess was added and more probably there was a chlorine leak or a boo-boo. Realize that this is speculation on the cause based on extremely limited information.

A. Hi, Valda. We metal finishers might be able to help with the side effects on the pool and building, but the question of side effects of this dangerous reaction on people is for doctors to tell you :-)

As Mr. Watts says, any analysis of the incident from this distance is speculation. But people can and do confuse bleach (sodium hypochlorite) with hydrochloric acid, and mixing them will generate chlorine gas and other nasty gasses.

I read of a major evacuation of a whole neighborhood when a tank truck driver asked a plating shop manager where "to pump the [mumble] hypochlorite" and the shop manager said "pump the [mumble] hydrochloric " into "this tank here", resulting in mixing the two in large volume. A good reason for us to not abbreviate or use slang when speaking of calcium hypochlorite and hydrochloric acid :-(

A. I re-read your question. First, to most of us, ingestion means eating or drinking it. If it is a gas, it would be inhalation. Second, toxic is in the dose -- a basic definition of toxicology. What was the product/byproduct of the event is anyone's guess because we do not know all of the items that were involved in the reaction. An approximate (very approximate) effect on the body would be to look up the MSDS for chlorine gas. Realize fully that there were probably trace amounts of other gasses.

A. The previous responses didn't fully answer your questions. Mixing bleach, or sodium hypochlorite with muriatic acid will liberate chlorine gas, which is definitely toxic, and a severe irritant to eyes and nasal passages and the lungs even in small amounts.

A. It's simple really, I work with chemicals all day long with swimming Pools and I was working with a former employee and he mixed the two by accident, it created a white toxic gas and nearly killed us both. The acid is strong if breathed in, but is deadly if mixed with chlorine. If breathed in, it's fatal.

A. Basically the combination of Muriatic Acid and Chlorine is mustard gas or a compound much like it. Very bad stuff, highly toxic and deadly in even small amounts. I spilled a small amount of acid on the floor where there was a small amount of chlorine powder from tablets for the pool and it made a fair amount of dirty cloud appearing gas. I breathed in a small amount before I got out and had lung and breathing problems for 6 months to a year afterwards.

A. Hi, Ray. As you see, we appended your inquiry to a previous similar thread which may answer it for you. You're probably lucky to be alive! For one thing, this reaction releases chlorine gas and other toxic gasses. Sodium hypochlorite or calcium hypochlorite is basically chlorine gas dissolved into a watery alkaline solution. If you destroy the alkalinity by adding acid, you destroy the liquid's ability to keep the chlorine gas in solution, and it is all suddenly released as an inhaleable gas.

You need written procedures that preclude it happening again. Good luck.

Regards,

A. Hi, Daniel. Call the doctor's office. The nurse answering the phone will ask you some questions and decide whether she thinks you should visit. If the person answering is not a qualified nurse who can help you, that indicates that you should be seeing a doctor but not that one :-)

Regards,

A. Hi Adam. I'm not here to be a stickler, but there is no such thing as hypochlorite acid.

Diluted bleach is often used as a disinfectant, but if the smell is too strong, you perhaps need to make it up more dilute. If "washing up liquid" is British for hand soap or dish detergent for hand-washing dishes, you can add it to diluted bleach without a problem. Good luck.

Regards,

A. Hi again Adam. The more we learn, the more we learn that there is no such thing as safe vs. unsafe . . . it's all relative. So if it smells really strong, try simply making it up weaker.

I don't know why you are doing this anyway though. I have heard of disinfecting once to stop mold after a flood, and I've heard of washing down a bathroom with diluted bleach, but I'm not familiar with anyone making a habit of washing their parlor walls with bleach. Unless the parlor of your farmhouse is also your abattoir or I'm misunderstanding in some way, I'd suggest stopping :-)

Regards,

A. Hi Eva. The neutralization of the acid with sodium bicarbonate did you no further harm. Sodium bicarbonate is just baking soda [on eBay or Amazon] and it was used to bring the pH back up from 2 to whatever pH you normally maintain. In reacting with the acid, it generated NaCl (table salt), carbon dioxide, and water -- all of which are harmless.
HCl + HNaCO3 => NaCl + CO2 + H2O

The tubs used chlorine as disinfectants, and the problem is that when way too much hydrochloric acid was added, bringing the pH down to below 2, the chlorine cannot stay dissolved in the water, but is released as a gas -- and breathing such an excess is very bad for you. The good news is that every doctor will understand the issue and be able to do for you what can be done.

Regards,

A. Hi again Eva. Muriatic acid is hydrochloric acid, HCl. "Chlorine tablet" is slang -- the tablets are actually calcium hypochlorite, Ca(OCl)2. Yes, mixing the two creates chlorine gas.
The reaction is: Ca(OCl)2 + 4 HCl => CaCl2 (harmless salt) + 2 H2O (water) + 2 Cl2 (chlorine gas)

Get well soon.

Regards,

A. Hi Ted,

Your responses are excellent, although I'm not sure how your metal finishing site swerved into answering questions regarding hotel spa chemical accidents! :)

I would like to respectfully offer one minor correction/addition, however: Although Calcium Hypochlorite or "Cal Hypo" is sometimes offered in tablet form, 3" "chlorine tablets" are more commonly trichloro-s-triazinetrione, otherwise known as "Trichlor." The net effect of the combination of this product with muriatic acid is the same: Chlorine gas is released.

  Thanks a lot Todd. Your question was probably rhetorical, but the metal finishing industry uses very large quantities of hydrochloric acid for pickling, and large quantities of sodium hypochlorite for wastewater treatment (destroying cyanide) and some other purposes -- so mixups and accidents that are chemically very similar can happen.

I already mentioned a major mishap requiring a neighborhood evacuation when a truck driver pumped thousands of gallons of sodium hypochlorite into a plating shop's hydrochloric acid storage tank rather than the right tank. I can hear the careless, shouted factory floor discussion in my head: "Hey buddy, (clang, clang) is this (brooohm, brooohm) the hypochlorite (garbled) (chih chih chih) tank?" "I'm in the middle of somethin over here pal, but yup, that there's (headnod, squeak, bang, sctitch) the hydrochloric (garbled) (screech, screech)."

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
September 2014

A. A big majority of commercial pools use far too much chlorine in their pools. Part of it is lack off knowledge, part of it is because they do not want to adjust the chemicals more than once a day or longer and part of it is management that do not want there to be any possibility of a health claim against them for not having a proper "sanitary" pool. More than a few people besides kids pee in the pool.

A. Hi Antonio. Actually, your employer should have a workplace injury reporting program which demanded that you go to the doctor immediately. Can't count the times I've seen signs: "Report every injury, no matter how minor!" This should have been reported by you seeing a doctor.

Regards,

A. Hi cousin Essa. It is important that you very clearly understand the difference between sodium hypochlorite (chlorine bleach) and hydrochloric acid or a disaster may await you. Whole neighborhoods have had to be evacuated when similar mistakes were made, and calling hydrochloric acid 'hypochlorite acid' is an invitation for that :-(

There is probably nothing which will be quite as effective as hydrochloric acid is quickly removing salt scale, but you can look up the MSDS for milder proprietary products like C-L-R (Calcium-Lime-Rust Remover) [on eBay or Amazon] and rinse everything first to somewhat dilute it before using the acid; or better yet, see if acid-free materials like Salt-Away [affil links] or Star Brite Salt Off [affil links] will do the job. Good luck.

Regards,

A. Hydrochloric acid (HCl) or Hypochlorous acid (HClO)?

Probably either one is overkill for removal of salts. Most salt scale can be removed fairly easily with a mild acid (citric, acetic, etc.) and even if your particular case needs a stronger acid, I would go phosphoric or sulfuric before hitting hydrochloric or hypochlorous.

All subject to environmental impact concerns as well. Like Ted said, many pH neutral products are available to do this also.

(www.globaltreat.com/on-site-chlorine-generator.php)

A. Hi again, Essa. Although we've talked about how to remove salt from pipes, I don't actually have any real understanding of what you are doing that is causing salt accumulation in the pipes so I am unable to offer suggestions on how to reduce it.

I'm guessing that your company builds chlorine generators, or operates them as a service, and that somehow the chlorine is used in fire protection, pump stations, etc. to discourage marine growth.

But I'm not really picturing what piping is accumulating salt or why. And when you speak of washing the skid, I assume you don't mean washing the skid, per se, but the inside of the piping which is mounted on the skid? Sorry, but I have no familiarity with that technology.

Regards,

A. Hi Gabriel. I don't know if "Don't Do It!" is the kind of suggestion you're looking for, but anything which can dissolve dead vegetation will wreak total havoc on the live stuff. And if your downspouts are aluminum, like most are, caustic materials will destroy them.

Try putting a water hose into the downspout from the bottom instead of the top (dress in old clothes, and do it when you already need a shower, it'll probably make a mess). Good luck :-)

Regards,

A. Hi Nicholas. Glad to hear you were wearing protective equipment and weren't hurt.
Yes, bleach is very strongly alkaline, so if accidentally mixed with acid will -- in addition to releasing dangerous chlorine fumes -- neutralize the acid. You probably need fresh acid if that's how you remove the plaster remnants from your trowels and shine them.

Regards,

A. Hi George,

Short answer: You will almost certainly be fine. See your doctor if you have any further recurring problems.

Long answer: Chlorine gas is a strong irritant (as you found out) and can be lethal in higher concentrations/prolonged exposure, but I think you will be alright in the long run. Just don't do it on a regular basis.

It was used as an early chemical weapon, but it is nowhere near as dangerous as mustard gas.

It forms HCl in your lungs, which is acidic and so will damage tissue, but not irrevocably so if the exposure wasn't very long.