# Mixing household bleach with urine

Hello everyone,

Not that I looking to experiment or anything, but anyway...correct me if I'm wrong anywhere here...please.

An associate of mine was wondering how to get rid of cat urine smell. Having exhausted all attempts to cover it up or use that enzyme stuff, I told him I usually treat the offending area(because I have 3 cats, I know)with a solution of household bleach. The ensuing reaction liberates alot of chlorine gas and that he should leave the area for a short time as chlorine gas is very irritating. (I do this all the time, and my kitties love me)
A friend strongly advised him not to mix bleach with urine because urine has ammonia in it. And the gas is toxic and will kill you.

Well first off I don't think urine has ammonia in it because urine is acidic. (Uric acid). The ammonia you smell from a cat's litter box is from the decomposition of the nitrogen rich by-products of metabolism. Correct so far?

Secondly the gas is chlorine because sodium hypochlorite is an oxidizer and it gives up it's oxygen in the process and liberates chlorine as a by-product.

Third the reaction is also somewhat of a typical acid-base reaction because bleach has a high ph and urine has a low ph.

I don't think I'm too far off base with the description of the reaction, or the origin of that ammonia smell, am I??
Please someone correct me if I'm wrong.

Also just out of curiosity, what would be the final products of a reaction with an oxidizer like sodium hypochlorite and uric acid and urea?
Carbon dioxide, water, sodium chloride. hmmmmm...where does all that nitrogen go??

Also what would the result of mixing ammonia and bleach? Hmmmm...?
I know it doesn't smell good, but do they even react?

Thanx for looking

Jim

turbo
Gold Member
Also what would the result of mixing ammonia and bleach? Hmmmm...?
I know it doesn't smell good, but do they even react?

Thanx for looking

Jim
You're kidding, right? You should immediately Google on "ammonia and bleach" for your own safety.

I figured chloramines were one of them. No, I have never mixed bleach and ammonia intentionally. Only accidentally once then immediately poured out he mix because like I said it didn't smell good.

Just mainly wondering about the danger of using a mild bleach solution to clean up after a cat?

there is probably no harm in cleaning up cat urine with bleach. i've worked with stuff like pure chlorine gas before and accidently breathed some in, but I am fine.Just work in a ventilated area in and you will be ok.

Mixing bleach and ammonia can be extremely dangerous

Per a quick Google search to verify:

There are several ways household ammonia and bleach can react. All of them are dangerous.

Reaction type 1: Ammonia directly reacts with bleach to form hydrazine (N2H4, which, in addition to being extremely poisonous, can burn even in the absence of air! It explodes on contact with rust!

2NH3 + NaOCl -----> N2H4 + NaCl + H2O

Reaction type 2: Bleach hydrolyzes into sodium hydroxide and hypochlorous acid, which in turn decompose into chlorine gas and nascent oxygen (both poisonous). The chlorine gas in turn reacts with the ammonia to form chloramines, also very poisonous.

NaOCl -----> NaOH + HOCl
HOCl ---> HCl + O (monatomic oxygen)
NaOCl + 2HCl -----> Cl2 + NaCl + H2O
2NH3 + Cl2 -------> 2NH2Cl (chloramine)
4NH3 + 2Cl2 ------> 2NHCl2 (dichloramine)
6NH3 + 3Cl2 ------> NCl3 (trichloramine or nitrogen trichloride)

{some of these chemicals have effects similar to phosgene gas on lung tissue and other mucous membranes}

You once mixed ammonia and hypochlorite "accidently"? You really need to pay more attention to what you're doing. Not only are chloramine gases very toxic, trichloramine is a contact explosive. If anyone here has ever observed Nitrogen triiodide, you'll know exactly how dangerous this is.

Yes, a household member of mine (don't want to mention any names) dispensed regular household ammonia into an empty spray bottle (for cleaning)labeled "bleach". I know, not good.
Well I dispensed what I thought was bleach into what I knew was bleach, then proceeded to dump the mixture out when I noticed something wasn't right.
This family member was immediatly instructed on the error of their ways.

I know about nitrogen triiodide. I made it once in high school. It has no practical purpose at all.

Thank you for all the advice everyone. I'm usually pretty careful, but I will be more carefull in the future.

Jim

Actually, humans and mammals excrete urea (not uric acid) in their urine. Birds usually excrete uric acid.

Urea is CO(NH2)2 (a structure analogous to acetone).

ShawnD
An associate of mine was wondering how to get rid of cat urine smell.
Not much of a chemistry answer, but try using Borax.

Hmmmmm....Borax, or sodium borate I beleive. What would be the reaction there?

Jim

ShawnD
Hmmmmm....Borax, or sodium borate I beleive. What would be the reaction there?

Borax has many chemical properties that contribute to its cleaning power. Borax and other borates clean and bleach by converting some water molecules to hydrogen peroxide (H2O2). This reaction is more favorable in hotter water. The pH of borax is about 9.5, so it produces a basic solution in water, thereby increasing the effectiveness of bleach and other cleaners. In other chemical reactions, borax acts as a buffer, maintaining a stable pH needed to maintain cleansing chemical reactions. The boron, salt, and/or oxygen of boron inhibit the metabolic processes of many organisms. This characteristic allows borax to disinfect and kill unwanted pests. Borates bonds with other particles to keep ingredients dispersed evenly in a mixture, which maximizes the surface area of active particles to enhance cleaning power.
So basically it's like Oxyclean.

kclo4x
I highly doubt that chlorine is released, its simply to reactive and its saying that NaOH is formed.... Wrong!
NaOCl does give up its oxygen but it makes NaCl, salt...

however dangerous chemicals are going to form, but for the small amount of urea that is in urine... i wouldn't worry about it!
even if your exposed to dangerous levels i'm sure you can heal because chlorine and i imagine similar chemicals do not leave long term effects

I'm sorry. I guess I was wrong then.

Just the gas released when I squirt bleach solution to clean up after kitty smells an awful lot like chlorine, because I thought the uric acid in the urine was reacting with the hypochlorite to give off chlorine in some way.

I know urine eventually contains ammonia.

But does fresh urine actually contain ammonia?

Is urine acidic or basic?

Thanx

Jim

fresh urine does not contain much ammonia due to the acidic condition of urine, you can usually tell by the smell, but the enzymes in the urine break down the urea to CO2 and ammonia over time, but if the conditions are changed to slightly basic, like with sodium bicarbonate, the production will be much quicker, unless you use a highly basic chemical like NaOH as it will denature the enzymes and possibly get rid of the smell, or prevent the smell, after that try a scented detergent.
I am not so sure about the bleach, but if it works, have good ventilation.

It works real good.

But if there is an excess (of old urine), you best be hoping you're on your way out of there.

Jim

I personally encountered the bleach/ammonia reaction when a hospital floor had to be evacuated in 1965. I believe that the same phenomenon was the cause of the Riverview Hospital (CA) emergency room incident in 1993 (bleach/urine reaction), the cause of which was never officially proven, and chloramine was never even considered by two investigative bodies.

Hey. Isn't urine alkaline and NOT acidic ?! Urine contains urea, uric acid and creatinine, with water and mineral salts as its main constituents.

I do remember peeing on universal pH-paper when i was 13 (HAHA)..it registered pH 9 = alkaline.

The reaction is between sodium hypochlorite and ammonia. Acidity is not required. The alkaline ammonia is a breakdown product of urea.

Borax has many chemical properties that contribute to its cleaning power. Borax and other borates clean and bleach by converting some water molecules to hydrogen peroxide (H2O2). This reaction is more favorable in hotter water. The pH of borax is about 9.5, so it produces a basic solution in water, thereby increasing the effectiveness of bleach and other cleaners. In other chemical reactions, borax acts as a buffer, maintaining a stable pH needed to maintain cleansing chemical reactions. The boron, salt, and/or oxygen of boron inhibit the metabolic processes of many organisms. This characteristic allows borax to disinfect and kill unwanted pests. Borates bonds with other particles to keep ingredients dispersed evenly in a mixture, which maximizes the surface area of active particles to enhance cleaning power.
So basically it's like Oxyclean.
I don't think it's correct; I think the author intended "perborate" not borax: borax is higly inert.

Hello everyone,

Not that I looking to experiment or anything, but anyway...correct me if I'm wrong anywhere here...please.

An associate of mine was wondering how to get rid of cat urine smell. Having exhausted all attempts to cover it up or use that enzyme stuff, I told him I usually treat the offending area(because I have 3 cats, I know)with a solution of household bleach. The ensuing reaction liberates alot of chlorine gas and that he should leave the area for a short time as chlorine gas is very irritating. (I do this all the time, and my kitties love me)
A friend strongly advised him not to mix bleach with urine because urine has ammonia in it. And the gas is toxic and will kill you.

Well first off I don't think urine has ammonia in it because urine is acidic. (Uric acid). The ammonia you smell from a cat's litter box is from the decomposition of the nitrogen rich by-products of metabolism. Correct so far?
Urine can contain ammonia, just for the reason you say, especially if you have some bacterial sepsi; the more urine is kept in vesica, the more ammonia forms. However urine contains urea, more than ammonia, and urea gives with bleach a similar reaction (of bleach/ammonia) so it generates chloramines and chlorine.

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Secondly the gas is chlorine because sodium hypochlorite is an oxidizer and it gives up it's oxygen in the process and liberates chlorine as a by-product.
Either liberates oxygen (becoming NaCl) or it liberates chlorine (becoming, in water, NaOH); it can't do both.
Third the reaction is also somewhat of a typical acid-base reaction because bleach has a high ph and urine has a low ph.
Normal urine it's quite similar to water, from this point of view, so that kind of reaction doesn't happen in normal conditions (anyway I don't know the exact composition of cat urine).
Also just out of curiosity, what would be the final products of a reaction with an oxidizer like sodium hypochlorite and uric acid and urea?
Carbon dioxide, water, sodium chloride. hmmmmm...where does all that nitrogen go??
Into...nitrogen!

I have had recent experience thus (in fact, the answer to this question has led me to this particular forum):

When cleaning out the clinical laboratory I work in I noticed a spill of human urine less than 4 days old in a plastic basin. Most standard operating procedures I have read call for a mixture of 10%household bleach (roughly 6% Sodium hypochlorite) and 90% tap water to clean up spills. I had no such solution handy and poured bleach into the basin. Upon mixture the two substances proceeded to react with the liberation of a gas. Upon allowing the basin to air dry I noticed some kind of residue stuck to the bottom of the basin. The residue appears crystaline and white and may in fact be sodium chloride. I have yet to verify this with any degree of research, though I am about to scrape this residue into a plastic test tube for further analysis.

To answer the human urine related questions in my experience human urine can be of any pH (this is part of the standard testing for urinalysis) and usually tests between 5 and 9. I notice that I get a pH of 5 or 6 most often, incredibly well hydrated patients (the ones with clear or light straw-colored urine, usually) present a pH of 7 most times. According to the Sixth Edition of Clinical Laboratory Medicine: clinical application of laboratory data (ISBN: 978-0-8151-7148-5, by Richard Ravel, copyright 1995, Mosby Inc.) normal pH of urine is 5-6 but can be between 4.5 and 8 (pg 147).

Because I didn't die or become seriously injured in my chemical idiocy, I hypothesize that the gases liberated were nitrogen or oxygen. That would make, according to the above poster, the residue sodium chloride.

NaOCl and Urine

I just stumbled upon this thread by realizing what I had just done.

I've not been to scared of bleach since I was little.

Let me do some explaining.

I have a horribly furry tongue which causes me to have very bad breath and it is very hard to get rid of.

So one day (after seeing how well bleach removes all kinds of dirt, colors, and bad odors) I decided to use some on my tongue. Do not get me wrong, I would not swallow any of it, or at least I tried my best not to. And it seemed to have worked. My tongue went from it's white color to a clean pink (tongue) color. So now I did this whenever I was about to go on a date. However, whenever I did this I would feel dizzy for several hours afterwards.

What lowered any level of fear I would have of bleach was that a friend at work told me that one of her friends was about to be screened for drugs and so she drank a whole bunch of bleach to "clean out" her system, she then threw up and passed the drug test. My friend told me that she would not have done that and would have rather be accused of taking drugs than drink bleach. I have never done any drugs nor drunk alcohol or smoked, but I agreed with her.

So the other day, I was watching the Military Channel. And they explained how mustard gas worked. And that it would cause severe rashes in soldiers. It can break actual bonds in one's DNA and cause cancer.

Then another day I was watching King of the Hill. And the episode was on where Peggy Hill had written an article on cleaning advice to mix ammonia with bleach to which Hank replied with fear that she had told people how to create mustard gas.

Fast forward to today.

We were out of soap and I was taking a bath. There was the bleach bottle next to the tub and I poured some into the hot water. The bleach felt slimy against my skin. And I remembered that someone had said that there is ammonia in urine.

Remembering that I got scared and read the label on the bottle and it said: Danger Corrosive.

This must have been the third time I did this. And to be honest I cleaned my private area as well, which may or may not contain small amounts of urine.

It's very strange that I only realized this now and how dangerous it is. It took 2 TV shows to make me realize this.

My body felt itchy all over untill a few minutes ago. But I think I feel OK now. Wikipedia says signs might not show for 24 hours.

I ask you, should I be concerned?

One thing I know for sure is that I'll never bathe in bleach or use it to scrub my tongue again.

chemisttree
Homework Helper
Gold Member
My body felt itchy all over untill a few minutes ago. But I think I feel OK now. Wikipedia says signs might not show for 24 hours.
I too get itchy all over when my life flashes before my eyes! I assume that you were taking a bath with a significant amount of water in it? And that you didn't put much bleach into the tub? (maybe a cup?) Chances are that you didn't do any permanent damage but I wouldn't make a habit of it.
Remember that your skin is composed almost entirely of protein in the form of dead skin cells. Lots of amines there that can react with bleach of course. You were probably only exposed to a high concentration of bleach during the short time just after you added it.

Was the bleach strong enough to bleach your body hair? Were your eyes burning and the fumes choking in the bathroom? No? Then just relax!

The bleach probably reacted with the stuff dissolved in the water pretty quickly and decomposed rapidly leaving behind only NaCl and NaOH (resulting in the slimy feeling). Your skin was probably more damaged by the NaOH in the bleach than the chlorine. Overexposure to chloramines or chlorine would result in some profound acute (acute = I gotta get outta here quick!) symptoms. You will probably only give yourself dry skin doing what (I hope) you have done. That feels itchy too...

Good idea to keep an extra bar of soap somewhere (like in your sock drawer) to keep you from doing this again. Of course you could have just used some shampoo and imagined you were using an exotic 'body wash' product.

Mixing diluted ammonia or urea with diluted chlorine is not dangerous and in fact is what goes on in swimming pools and spas. The reactions are as follows:

2NH3 + 3HOCl --> N2(g) + 3H+ + 3Cl- + 3H2O
Ammonia + Hypochlorous Acid --> Nitrogen Gas + Hydrogen Ion + Chloride Ion + Water

(NH2)2CO + 2HOCl + $$\frac{1}{2}$$O2 --> N2(g) + CO2(g) + 2H+ + 2Cl- + 2H2O
Urea + Hypochlorous Acid + Dissolved Oxygen --> Nitrogen Gas + Carbon Dioxide Gas + Hydrogen Ion + Chloride Ion + Water

If you were to use concentrated solutions, especially of chlorine, then you can form higher order chloramines including nitrogen trichloride which smells really bad and is irritating and in sufficient concentrations dangerous.

As for producing chlorine gas, I think you are thinking of adding a concentrated acid to chlorine bleach or chlorinating liquid which does indeed liberate chlorine gas as follows:

HOCl + H+ + Cl- --> Cl2(g) + H2O
Hypochlorous Acid + Hydrogen Ion + Chloride Ion --> Chlorine Gas + Water

Bleach and chlorinating liquid and other hypochlorite sources of chlorine (such as lithium hypochlorite and even Cal-Hypo) contain hypochlorite ion, OCl- as well as chloride ion, Cl- so one should NEVER add acid to these compounds in concentrated form.

So adding a dilute solution of bleach to a litter box to remove ammonia/urea, which was the original question, is perfectly reasonable, but it should be a diluted solution since not that much chlorine is required.

As for exposing oneself to concentrated solutions of bleach or chlorinating liquid, this is definitely bad. The chlorine in water is a strong oxidizer so it will start oxidizing your skin, tongue, etc. though in saliva it will mostly oxidize the organics found there. In concentrated form, when chlorine combines with organics it can form compounds that are possible-to-likely carcinogens including chloroform (from chlorine+organics) and nitrogen trichloride (from chlorine+ammonia/urea). Obviously, concentration is everything -- swimming in lower concentrations found in pools, especially when Cyanuric Acid (CYA) is present and significantly reduces the disinfecting chlorine (hypochlorous acid) concentration to an equivalent 0.1 ppm Free Chlorine (FC) if no CYA were used, is quite safe. Drinking water used to be chlorinated up to around 1 ppm FC though now monochloramine is typically used. More technical details on pool/spa water chemistry may be found in http://www.troublefreepools.com/viewtopic.php?t=628 [Broken].

As for your bleach added to a bath, you probably didn't add enough to cause serious harm beyond skin irritation -- but obviously don't do this again. By the way, it feels slimy mostly due to it's high pH and if the water in your tub was relatively unbuffered and you added a large enough amount of bleach, then the pH may have been high enough to make the water feel slimy on your skin (similar to how a solution of sodium hydroxide, lye, feels).

Richard

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