The Chemistry of Dried Pee

PLEASE forgive me if this or similar has been discussed already; I did search, but you would not *believe *how many hits you get for “urine” on these boards.

So I have a pissy cat. Determining why she is pissy is a work in progress (and yes she’s cleared by the vet, and please don’t start in with me about litterboxes etc.). However, a more urgent work in progress is un-stinking that which she’s peed on. I decided to take a risk on "Scoe 10X " and have just tried applying it for the first time today. It’s too soon to tell whether it’s worked completely, but so far – while the test subjects are still damp with the stuff – I’m impressed. I’m thinking of dousing most of the house and/or investing in the company, if long-term results are as good as I’m hoping they could be.

Here’s my question: the site that flogs this stuff contains the following explatory and elucidational text:
As urine dries, the ureas in the urine form hard crystals or salts (much like table salt), while the fats, hormones and numerous other chemicals found in urine, coat and literally glue the urea crystals to whatever the urine comes in contact with. This coating action of the other chemicals act as an impermeable water barrier which inhibits re-hydration of the urea crystal. Consequently, urine residue locks itself on and around any fiber (carpet especially) or material it comes in contact with, and by drying, forms an almost impenetratable water barrier which greatly complicates removal. Can any IAAChemist or IAAScientist Dopers confirm or refute this seemingly reasonable narrative? (No points for pointing out “impenetratable” etc. because even the most genius-est chemists aren’t required to be good proofreaders.)

I don’t know the answer, but I just wanted to chime in and say that’s an interesting question. I looked through the product’s web site and am wondering whether it really works as advertised. Let us know.

If (and I’m not saying it isn’t) that was the case, wouldn’t something like naptha work as well?

I appreciate the sentiment, but I’m not asking whether Scoe 10X is the ONLY substance that could overcome Super-Coated Urea Crystals; I’m asking whether Super-Coated Urea Crystals is really the secret identity of the villain.

It’s reasonable, to some extent. Seeing as the constituents of urine were initially water soluble though, I would expect that with the proper pH, it would eventually go back into water solution; however, while something may (this is going to get technical) be thermodynamically soluble they may not be kinetically soluble. That is to say that while X amount may be able to go into solution, it may take lots and lots of work to get it into solution. In this case, small crystals may go into solution very easily, but due to their reduced surface area larger crystals do not.

Another factor that this article alludes to, is that the organic components of urine may well be attracted to the organic molecules in the carpet. This would also increase the difficulty of cleaning. Of course if they were so attracted to the carpet that they could not be removed, you wouldn’t smell them.

The real problem is the incredible potency of the molecules you are smelling. You can probably smell them below the parts per million range. Since removing these molecules is allready difficult, simply washing them away is not going to be effective.

Any idea what that pH might be? IANAC, but I can use pH strips.

No kidding. I TOTALLY believe the idea, but… cite?

Are you referring to the practical difficulties of washing things that cats like to pee on (in my case, futons and irreplaceable, non-immersible embroidered things)? Or are you referring to a difficulty in washing away molecules that may or may not be crystals enveloped in insoluble fats?

You probably want a vet rather than a chemist for that cite. We don’t get too many cat pee articles in JACS. :wink: Given that one of the points of urine is to mark territory, I only assume that some components are quite potent. It is not uncommon for compounds to smell bad below the part per million range. Just ask any thiol chemist about that.

I’m refering to the difficulty in washing them away at all.

What the article you posted says, is pretty reasonable. I am not certain that a significant quantity of urine has fats. Certainly, the fats are not insoluble, because they had to be in solution in the first place to get through the cats kidneys and onto the floor. From here, it doesn’t seem that there is a significant quantity of fats in cat urine. Still, its a better question for a vet.

Don’t bother. Use an enzymatic based cleaner on all animal urine. In my experience, bleach workes fine as well, but is probably not good on carpets.

The enzymatic-based cleaners I’ve used (Natures’ Miracle, Anti-Icky-Poo) haven’t been successful, and bleach is contraindicated on many of the items I’m treating, which is why I went looking for something new.

Any vets who can comment on the chemical properties of dehydrated cat pee? er, that’s dehydrated pee from cats, not pee from dehydrated cats.

Re: bleach, watch out - I’ve tried to clean something in my aunt’s house so cat-pee-ful that the bleach produced noxious clouds and ran me out of the room. I imagine most pee stains don’t have enough ammonia in them to make a difference, but do remember that there is ammonia there.

I’m missing how each and every water soluble crystal in the urine could/would be perfectly coated in organic material such that no water could penetrate. Sounds improbable to me. Realistically the organic materials will bead up. Any exposed area on a salt crystal would then be open to water penetration, dissolving the crystal. It’s not like these crystals are being individually formed and then dipped in organic resin.

More likely to me (keeping in mind I’m a chemist, not a vet) the organic compounds themselves are the stink producers. Urea doesn’t smell nearly as bad as whole cat pee. (or even half cat pee!) Organic materials are harder to remove with traditional cleaners. Better to get enzymes in there to break them down. Enzymes are very good at their job.

I’m sorry and surprised the Nature’s Miracle didn’t work for you. I have found that I’ve needed a repeat application in some cases, and keep in mind it doesn’t work immediately but requires several days to work and then dry completely before the smell is gone.

I imagine by the time she’s gotten to the stage of having tried all that she apparently has, there is no real ammonia left. Good advice about using bleach with proper ventilation though.

I must admit, emilyforce, if the Natures Miracle hasn’t worked you have a problem. Are you sure that you are getting the product on where the smell is coming from? Are you letting it sit long enough? I know you know how to use it, but I’ve always had pretty good success with Natures Miracle so I wonder if maybe there is something obvious. If your cleaning a cushon, the cat pee could be very deep and the Natures Miracle just isn’t reaching it. It has nothing to do with fat coated insoluble crystals, because Natures Miracle is made for that.

Aside from Natures miracle, you might be able to try OxyClean (sodium percarbonate) or another color safe bleach. Try it first to make sure it really is compatible with what you are cleaning. Even hydrogen peroxide might help, but once again try it first to make sure it is compatible. The idea is to oxidize the smelly compounds. I suspect (without any cite but if you google thiol and caty urine you will find that many thiols smell like cat urine) that some of the smelly compounds are thiol based. Oxidizing the thiol will releive the smell of these compounds.

I think so. I’ve followed the label instructions faithfully, and the smell definitely got better, but not gone. Part of the problem is that the cat now has a “substrate preference” – meaning she likes to pee on things that feel a particular way – and she will go out of her way to re-offend on anything with the tiniest hint of smell left. (And yes, I’m addressing the preference/behavior/issues/etc. separately).

Hmmn. This is very interesting. I will try this next if the Scoe stuff isn’t a knockout.

I’d just like to join in and point out that my experiences with Nature’s Miracle were less than miraculous, as well. In fact, it barely worked at all, and I followed the instructions religiously.

The only thing that has stopped the pee issues with my cat has been cleaning the litter box literally after every use. She uses it, we clean it. If we’re away for a while (hours, not days) we clean it when we come back.

The pee issues have stopped and we’re looking at replacing the couch soon. But it was not a fun process to go through.

Anyway, my point is, what you’re describing sounds very much like what I went through, and we tried everything ourselves before someone (here, as it happens) suggested cleaning the box every time she used it. So… have you tried that? :slight_smile:

ETA: I just noticed the ‘please don’t start’ bit about litterboxes. Oops, maybe. The only alternative I have to offer was, oddly enough, a steam jet. The steam shark (I think that’s what it’s called) removed the stains and smell from the carpet and couch, when caught soon enough, but required quite a bit of work. Time, rather than elbow grease, but still.

I don’t think there should be any fats in the urine of a healthy cat, though IANAV.

Heh! You have become cat-slaves indeed. :stuck_out_tongue: Good humans!

No, that is not an option at present; we actually have three cats and one dog. The litterboxes have to be where the dog can’t, uh, sample from them – so the basement door is fixed open at all times, wide enough for cats but not dogs to go through. To keep all five litterboxes perfectly clean at all times would take some kind of remote sensor alarm system, and possibly a live-in litterbox care assistant. And to boot, the Demon Princess (the peeing cat) has chosen more than once to pee on piles of fresh laundry instead of sparkling clean litterboxes. She gives bonus points for fresh laundry piled on couches or beds. Of course, we have now stopped leaving piles of laundry unchaperoned anywhere, but the smell on the non-launderables (and a few launderables, blecch) remains.

I do try to scoop the boxes twice a day. There are probably social factors involved – who gets to be the “dominant cat” in the house has never been fully established, for starters.

I’ve just received ammo for our latest plan of attack, on our vets’ advice: they tell me that cats usually avoid any citrus smell. Therefore, I ordered some all-natural grapefruit air freshener and some heavily perfumed (with natural oils) laundry soap in “Italian Citrus” flavor.

</self-induced hijack>

The jury is still out on the Scoe 10X. One application as directed didn’t finish the job, though it did improve things. The makers do advise that, owing to the aforementioned chemistry, dried cat pee often requires more than one application. I think three’s my limit, though.

Somehow I missed this. I generally agree. For one thing, as I have mentioned, cat urine is not likely to have completely insoluble material in it in the first place. Second, I don’t think that soluble fats are a large portion of urine content (not a vet, just a guess). However, whether or not the entirety of the statement she gave is precisely correct, you have to realize that the crystalization process is all about order. Without direct experience with the particular chemistry, you can’t really say how the precipitate is going to be ordered. Maybe the acids dimerize first followed by the organics, leaving small capsules. The organics are likely to be very “freindly” with the organic polymer of the pillow/cushion…

These ordered processes aren’t uncommon at all, especially in the area of precipitated solids. The entire science of nanotechnology depends on it. There is no way to make the blanket statement that the statement emilyforce provided is wrong in the laypersons sense. It’s just too damned likely.

So there you go emilyforce. You have the two contradicting opinions of chemists regarding that statement. Sometimes thats the way good science goes, and I personally don’t hold it against Solfy in any way. She may have a better idea than I do.

Points taken, **Christopher **and **Solfy **-- though please do note that the original doesn’t say completely insoluble, just

and doesn’t attribute this relative impenetrability to just fats, but to

. Would that make you think differently about Solfy’s objection?

I’m not saying there’s no order to the crystallization, I’m just objecting to the product manufacturer’s claim that the odor comes from the urea and the urea is hard to remove because it’s all capsulated by the organics. That’s too perfect for me. You could say it’s simplified for the layperson, but that smacks of voodoo handwaving.

Consider the differences between urine drying on a vinyl surface (say, a waterbed mattress) vs. urine absorbed in car floor carpeting vs. urine soaked into a reclining Action Lane sofa. It’s going to have different drying rates, different substrates soaking up different components differently, etc. It’s always going to be stinky and removing the smell will always be difficult. I don’t believe this can be attributed only to the crystallization matrix of the urea and other organic compounds, nor do I believe that such a matrix makes removal by aqueous solutions impossible. I think removing water soluble components (whether they’re coated in organic residue or not) isn’t going to do a thing to make your couch smell better.

I also have a little experience in this area, sadly. (as can be seen by my rather specific examples) I had a cat obsessed with peeing on our waterbed. The only solution was to remove the waterbed. (we were going to anyway) I have a recently toilet trained child who peed on the couch. Twice. Our couch doesn’t have removable cushions. It took months before I felt the couch smelled remotely acceptable, and I’m still planning on having it professionally steam cleaned.

Urine in fibers is a pain in the nose, no matter which way you slice it. Too much surface area, too hard to get to.

In their defense, the next paragraph after what I originally posted is:

It sounds like they’re saying the problem isn’t encapsulation alone, but rather that the organics help the urea stick to fibers *and *help keep water from washing it off. In all their literature, they repeatedly make the point that their stuff can only neutralize those molecules which it actually touches, and that most “failures” are really failures to soak your stinky thing in enough stuff. (Eyew. That almost sounds perverted.)

The next paragraph after that is:

Presumably the bacteria have no trouble chewing through the same organic raincoat that helps keep water out.