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Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

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Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#151

Post by matteuan »

amelius wrote: post #77
sizzzzlerz wrote: post #12

I've always wanted a product that you could add to the swimming pool water that reacts to human urine by coloring the water immediately surrounding the pee-er. Say a neon orange or red. Over time, the colored water gets diluted and disappears. Maybe pee-shaming is what's required to stop people from doing it.

How bad is urine really, in the quantities found in a typical pool? Remember that doctors used to taste urine, to test for e.g. diabetes.

even if the pool contained only urine, I don't think there would be any particular health hazard. Maybe if you drink too much of it, you could get some kind of salt poisoning, but then the same risks would occur when swimming in the sea.

Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#152

Post by disillusioned »

trentlott wrote: post #36
sizzzzlerz wrote: post #12

I've always wanted a product that you could add to the swimming pool water that reacts to human urine by coloring the water immediately surrounding the pee-er. Say a neon orange or red. Over time, the colored water gets diluted and disappears. Maybe pee-shaming is what's required to stop people from doing it.

I vaguely remember this being a plot point in an episode of 'The Adventures of Pete and Pete'†. I'm sure there are plenty of chemists that have valiantly attempted to find something that could both stay stable in UV-blasted chlorinated water and react with a weak acid to give an absorption in the visible wavelength. . .but that is a very long and hard-to-fulfill wishlist. Anyway, it's just any sort of amine reacting…

Pete & Pete continues to be one of those weirder shows that definitely messed me up from watching it as a kid. I seem to have some weird suppressed memory of a brain freeze episode as well. Weird stuff.

Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#153

Post by wildmusings »

danielpal wrote: post #144

another shocker. The smell of "Chlorine" in the pools is not caused by "chlorine" but by the urine. Chlorine has no smell when mixed with water. Add urine, and you get the "Chlorine" smell thats typical of pools. See: https://www.youtube.com/watch?v=S32y9aYEzzo&t=607s&frags=pl%... https://chlorine.americanchemistry.com/Science-Center/Chlori...

Kind of a deceptive video, which might make you think that if no one peed in the pool, there would be no pool smell. Urea is what reacts to create trichloramine, which gives off the smell. But urea, as the video acknowledges, also comes from sweat. Yet they go on to talk about chlorine reacting with urine as being the sole cause of the smell.

They should have gone into what percent of the urea comes from sweat vs. urine.

Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#154

Post by kisstheblade »

amelius wrote: post #77
sizzzzlerz wrote: post #12

I've always wanted a product that you could add to the swimming pool water that reacts to human urine by coloring the water immediately surrounding the pee-er. Say a neon orange or red. Over time, the colored water gets diluted and disappears. Maybe pee-shaming is what's required to stop people from doing it.

How bad is urine really, in the quantities found in a typical pool? Remember that doctors used to taste urine, to test for e.g. diabetes.

Urine is sterile. That's why it's good to pee on wounds.

Edit: Wow, what harsh downmodding :) Yes I was wrong and learned something, isn't it still useful to keep my comment here for other's education? I literally heard this "urine is sterile" comment in the last couple of weeks. I stand corrected, thanks!

Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#156

Post by michaelmrose »

supermw wrote: post #107
ams6110 wrote: post #74

Earlier quoted context omitted.

Or the other way to look at it, is that there's so much bacteria, algae, rotting plant and animal matter, bird shit, fish shit, etc. in lake and pond water that a little human urine won't appreciably add to the risk of swimming in it.

If that's true then why do people go nuts if you shit in a river while camping?

They are picturing themselves drinking your shit most likely.

Historically human beings contaminating the same water they draw from has been a substantial cause of illness even if campers now are much more apt to get water from a bottle.

Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#157

Post by amluto »

keypusher wrote: post #47

Chlorine reacts with pretty much any organic compound (hair, sweat, skin, urine) to produce chloramine. And yes, while this is the thing that irritates your eyes, it's not to say that chlorine is harmless either. There is evidence for respiratory and organ damage from extended exposure to chlorinated pools. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4351252/

That study seems dubious -- they mention that they measured free chlorine with a DPD test, and they also say that they measured chloramines with a colorimeter and the DPD test. This seems quite odd -- the distinguish between free and combined chlorine (which mostly means chloramines), a better test such as FAS-DPD should be used. So I don't see how the study determined what the cause of the problem was, but it certainly spends quite a bit of time explaining how chloramines can be problematic.

Anyway, chloramines can be controlled to some degree. The use of stabilizers (cyanuric acid) can reduce the amount of nitrogen trichloride (the worst chloramine) in the water by a considerable amount. As I understand it, the factors that make the biggest difference, though, are maintaining adequate chlorination and exposure to UV light. UV light (from the sun or a UV lamp) breaks down chloramines. So the best solution is to swim in an outdoor pool :)

(The FAS-DPD test is a standard test kit you can buy from ay reputable dealer. It's a titration, not a colorimetric measurement, so no fancy equipment at all is needed.)

Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#158

Post by 00N8 »

sizzzzlerz wrote: post #12

I've always wanted a product that you could add to the swimming pool water that reacts to human urine by coloring the water immediately surrounding the pee-er. Say a neon orange or red. Over time, the colored water gets diluted and disappears. Maybe pee-shaming is what's required to stop people from doing it.

we allegedly had just such a product in use in my high school swim class

it was almost certainly fictional, but it still might've worked

Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#159

Post by Domenic_S »

jedberg wrote: post #65
xiii1408 wrote: post #21

This has been well-known by swimmers for a long time: chlorine itself is pretty much fine for you. It's the chemical reaction of chlorine with waste products, including human waste, that produces toxic byproducts and the concomitant "pool smell." If you swim in a well-maintained pool (e.g. one of my university's competition swimming pools), there's no "pool smell."

Are you sure your University isn't using bromine instead of chlorine? Bromine is more expensive but then you don't get the "pool smell". It's what they use at Disney parks.

A well-maintained & chemically balanced pool should not smell under typical circumstances.

I owned a 40,000 gallon in-ground pool and followed a method called the "Trouble-Free Pool method". The only chemical requirements are normal bleach (chlorine) and a pH adjuster. No "shock", no algaecide, no pool store shenanigans. My pool was pristine & sparkling blue, and never smelled or hurt guests' eyes or turned blonde hair green. My family (including two small children) could swim all day long and never have irritated eyes.

It's really about being very careful about the chemistry (step 1 is to get a high-quality testing kit). Public pools are... less than fastidious about chemical balance and standards are much looser.

Re: Pee, Not Chlorine, Causes Red Eyes from Swimming Pools: CDC (2015)

#160

Post by ghostbrainalpha »

Stevvo wrote: post #109
g051051 wrote: post #103

I've been in pools that I'm 100% certain no one had peed in, and still got red eyes. I'm certain because I was the only one who swam in it (a backyard pool) and I know I never did.

Probably peed in by wildlife

Ambient pee if you will. Or background pee from the hose used to fill the pool.
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