I think the nasty crap I see in lakes that I ultimately swim in is much more concerning, or maybe the crud on the locker room floor. But, none of it bothers me very much at all.
Aren't you sweating a lot in the pool anyway?
"Reduces sweat." Even if you sweat again in the pool. And what about the "other bodily fluid" and other stuffs? :rolleyes:
Some people dive into the pool right after an hour of treadmill exercise, soaking wet with their sweat, and use the pool as a bathtub. :shakeshead:
I'd like to hear a chemist chime in here, but my understanding is the concentration of elemental chlorine gas in a pool's atmosphere is going to be pretty close to nil. Chlorine compounds, yes, but chlorine, no. It's so reactive it doesn't stay in its elemental form for long. Now I also know that some tiny fraction of molecules are going to crack apart in water - even tap water has some free H and OH ions in it. Whether chlorine ions get produced in the pool and if so how long they remain as ions when the reach the air is what I'm not sure of.
The thread title is misleading. The potential danger is not from chlorine gas directly. Chlorination can be done either using a hypochlorite salt or by elemental chlorine, which as you note dissolves and reacts pretty quickly to form hypochlorite (there will be some small dissolved chlorine gas remaining but not very much). Pool pH control is essential to have the right balance of hypochlorite (OCl-) & hypochlorous acid (HOCl); it is the acidic that is more effective at killing pathogens. I believe hypochlorite salts are generally used for (chlorinated) swimming pools, while chlorine gas tends to be used for drinking water and sewage disinfection.
It shouldn't be all that surprising that things that are meant to kill bacteria etc might have health effects on nontarget organisms, but most of the risk is not from HOCl & OCl- directly but from reactions involving them. Chloramines are produced by the reaction with ammonia and organic amines (including urea). A number of disinfection byproducts (eg chloroform and other trihalomethanes, THMs) are also produced by the reaction with other organics.
Of course the risk from these things is less than the risk posed by disease if the water is not disinfected. But there are potentially better ways of sanitizing the water. The facility I swim at has two pools, one of which uses uv disinfection and the other uses ozone. The reason they went to these systems was that, with chlorination, the air quality was so bad that most of the kids were hacking and some were having more serious respiratory problems. The pool is great now; (light) chlorination is used as a backup when necessary.
Most civil or environmental engineering or wastewater treatment references will tell you more than you ever want to know about chlorination chemistry.
Showering before entering the pool (reduces sweats and other bodily fluid and anything undesirable in a pool)
Aren't you sweating a lot in the pool anyway?
Chlorine Can React With Sweat, Urine At Indoor Swimming Pools Forming Volatile Disinfection Byproducts
Researchers at Purdue University have determined how certain airborne contaminants are created when chlorine reacts with sweat and urine in indoor swimming pools, a step toward learning how to reduce the formation of "volatile disinfection byproducts" that cause respiratory irritation.
"Some indoor swimming pools seem to have a characteristic chlorine odor," said Purdue environmental engineering professor Ernest R. Blatchley III. "You may think you're smelling chlorine, but you are probably smelling a mixture of disinfection byproducts. If their concentrations get high enough, then they can become an irritant to your respiratory system, to your skin and to your eyes."
What's In Your Water? Disinfectants Create Toxic By-Products In Drinking Water And Public Swimming Pools
Plewa said that studies were showing higher levels of bladder cancer and asthma in people who do a lot of swimming - professional swimmers as well as athletic swimmers. These individuals have greater and longer exposure to toxic chemicals which are absorbed through the skin and inhaled.
You actually lose a couple pounds in water during a good swim. We have an actual scientist in our group and he explained it to me. It's not sweating, it's osmosis or something like that. He mentioned the term 'osmolality' and said it's the same process that causes your fingers to wrinkle.
I'd like to hear a chemist chime in here, but my understanding is the concentration of elemental chlorine gas in a pool's atmosphere is going to be pretty close to nil. Chlorine compounds, yes, but chlorine, no. It's so reactive it doesn't stay in its elemental form for long. Now I also know that some tiny fraction of molecules are going to crack apart in water - even tap water has some free H and OH ions in it. Whether chlorine ions get produced in the pool and if so how long they remain as ions when the reach the air is what I'm not sure of.
Chemist chiming in here.
The "chlorine" in your pool water is hypochlorous acid, which is the same thing as household bleach. This acid contains chlorine atoms (HOCl) but it is different from chlorine, just like water (H2O) is different from hydrogen. This acid, and its byproducts, do cause skin and eye irritation, fabric damage, etc.
There certainly will be a lot of chloride ions (Cl-) floating around in the water. Those are the same ions that are found in salt water -- completely harmless, odorless, non-allergenic, etc.
The amount of elemental chlorine gas (Cl2) above the pool should certainly be very, very small, unless there is something terribly wrong with the pool's balance.
Dedicated (and undedicated) swimmers, it will do no harm, and perhaps infinite good, to you, your loved ones (assuming they love you in return), and your lane mates, by:
Showering before entering the pool (reduces sweats and other bodily fluid and anything undesirable in a pool)
(How hard is it to do so? :cool:)
Getting out of the pool into the bathroom when you have nature's call
(Or you yourself would be in the closest vicinity of combined chlorine and organic compound = THMs = carcinogen :cool:)
(I believe there were discussions about this here in the past. Just search for chlorine and cancer.)
The other day I swam in a heavily chlorinated pool, it burned my nose, and another swimmer said it burned her eyes. My goggles would get a thick layer of white build-up around the frames after swimming in that pool for just a few days, but it gets nothing after more than a year of swimming in another pool. I wonder if those white stuffs could penetrate my skin, like salt and sugar? :rolleyes:
