OK not killed but maybe harmed in some way. Here’s my logic.
Our body is covered with over 600 different kinds of bacteria. These bacteria make up the ecosystem of our body. Though their role is not well understood, they must certainly provide some benefit to our body. One study that I read linked too much washing with diseases like asthma (just a theory).
So when we swim in chlorinated water, many (most? all?) of these bugs must be killed. Why aren’t we harmed by this?
If we were to stay in an overchlorinated pool for too long wouldn’t all these bugs be killed? How would we get them back?
“Much of our experience with bacteria involves disease. Although some bacteria do cause disease, many kinds of bacteria live on or in the human body and prevent disease.”
The key word id IN your body and not ON your body. There are some essential bacteria in the body such as those that help break down food and plenty of others that help keep systems in check. You aren’t killing those when you swim. Most pools aren’t very strongly chlorinated anyway so your skin won’t be completely sterilized. Our bodies are used to a good surface cleaning and people use all kinds of strong chemicals on their bodies routinely.
You’re thinking of the hygiene hypothesis. Very basically, it is thought (but by no means proven) that a lack of exposure to pathogens will result in an over-active immune system that goes after random allergens instead. I’m not sure that beneficial bacteria are attacking our pathogens, as you imply.
I’m not sure of the beneficial roles of bacteria on our skin, but they’re absolutely everywhere. Even if you did kill every one of them, you’d pick up fresh cultures probably any time you came in contact with another person, or touched anything that wasn’t sterilized.
Actually, this sounds like a good topic for a home science project…
A lot of “Nuetral” bacteria helps us. Don’t foget unlike a virus a bacterium is alive and a living in its own right.
Bacteria that live on or in us and neither help nor hurt us can help us by crowding out the “evil” bacteria.
Bacteria fight for position. And if a bacterium can’t get food and “room to move” to reproduce, it dies. If the neutral bacteria in our bodies are so abundant there is no room for the bad guys so in that way the nutreal bacteria helps us.
There are bacteria than CAN live in nuclear waste and bleach. Most cannotbut a few kinds can so they are hardy little buggers.
Also remember the top layer of your skin is dead anyway, you have to go down a couple of layers.
I think there’s a possibility that you’d pick up the wrong culture - and that in the absence of competition, that culture could cause some kind of skin infection. I suspect part of the reason it doesn’t seem to happen (if indeed our normal skin flora is significantly depleted by swimming) is that afterwards, you put your clothes back on and all the normal strains are reintroduced. Even if you don’t get dressed back into the same clothes, you will probably sleep in the same bed later, or sit in the same chair, etc.
Good point, I never thought of that. But it would likely take them several days to reestablish a population and in that time other bad bugs could take root.
I’ve never heard of pro swimmers being sick more often than non swimmers so maybe your natural population serves no purpose or maybe chlorinated swimming pools just aren’t strong enough to do the trick.
I think the main point to keep in mind is that your external skin is designed (and works pretty well) to keep things out, things like bacteria and their by-products. I’m not aware of any effects on the body from bacteria or fungi etc. on the skin (except in providing the I’m-past-puberty scent). Get rid of them all, and your body won’t notice much.
This is in contrast to your intestines, where bacteria do affect your digestion a lot.
Most chlorinated pools maintain a chlorine concentration of about 2 ppm (parts per million), which is enough to keep the water clean and sanitary and to keep it comfortable, but not enough to sterilize the water. The pool I’d worked at (many, many moons ago) would “shock” the pool weekly. To pretty much sterilize the water, we would add enough granulated chlorine (sodium hypochlorite, IIRC) to bring the concentration up to 6 ppm. This may not sound like much, but it was enough to bleach some stuff out that had remained in the pool overnight.
Sodium hypochlorite breaks down rather quickly in sunlight, so we would add the granules right after the pool had closed Saturday night. By the time the pool opened at Noon Sunday, the concentration would be down to 2.5 - 3 ppm. That’s a slightly uncomfortable, but not irritating level.
To more directly answer the question, if the pool had a chlorine concentration high enough to kill everything on your skin, it would also be high enough to start to kill your skin. No pool owner would like to be known as the place to get the best chemical burns in town.
Many years ago, I read about a small company that was marketing a form of copper sulphate as an alternative to chlorine, to keep swimming pools clean. The idea was that CoSO4 would never break down, and it would be less irritating than chlorine. I never tried it, and never heard of it agian-anybody know what happened to it?
CuSO4 is a big biocide (commonly used in naval paints and, in spray form, for agricultural uses), but it’s poisonous to humans and it can speed up corrosion in conditions that don’t include lots of Cl- and I- (the sea does).
We tried it for a part of one summer. It had started to turn the white vinyl paint green. As I had just spent the better part of two weeks stripping and repainting the big pool, the intense hatred I had for that device is nearly unmatched.
Sorry. My remark stands, but disregard the question.