We just moved to Houston, TX from Florida, and have discovered they put chloramine in the water supply. Are we drinking and bathing in Drano (plus, aspirating it during showering)? How dangerous?
Not dangerous at all. It’s used because it’s less likely to break down than straight chlorine. Chlorine treated drinking water that hangs around in pipes can start to grow organisms when the chlorine levels drop below the amount required to kill bacteria. Chloramine, NH2Cl is much more stable. You can get by with adding less and still keep the drinking water safe.
Drano is primarily composed of sodium hydroxide (better known as lye) and potassium hydroxide.
It’s probably not safe. They probably didn’t even conduct any studies or have an scientific data to go on at all. They probably don’t even live in the community themselves, or have kids. Probably.
Here - Drinking Water Regulations | US EPA
Municipal water treatment requires a disinfectant mechanism to ensure the water wont harm you. It has been determined that chlorine works but chloramine works better given the balancing act between cost, monitoring, harm reduction and effectiveness.
It’s bad if you want to make beer out of it, though.
Yucky plasticky flavors are the technical description.
The only thing I’d watch out for with chloramine treated water is your fish tank or certain kinds of sensitive plants. Because chloramines are more persistent than straight chlorine, it’s a good idea to either treat the water (check your local pet store) or let it stand for a day or so before using the water.
You need to treat it. We discovered the hard way with some African dwarf frogs that letting it stand wasn’t good enough.
Heh. Thats funny. 
Sadly, that’s true. Chloramine will not disperse on its own like chlorine does, so it must be chemically neutralized before using it for fish.
As for home-brew beer, my brewer friends in CA would frequently visit a nearly public spring for all the free spring water they could carry home.
It’s a good bet that if it kills harmful bacteria it won’t do brewer’s yeast any good.
It’s also a good bet that using untreated water for homebrewing is a wildly bad idea, but that’s a different subject. People who use tap water for beer & such have to boil it for fifteen minutes first (this deactivates the chlorine somehow… never tried it myself). I don’t know if that would work for chloramine, though.
Boiling or vitamin C apparently will do the trick. This is from the San Francisco Public Utilities website.
Sodium metabisulfate or Ascorbic Acid will “dechloraminate” your water.
It isn’t so much the effect on yeast, but funky phenolic flavors/aromas that chlorine can create.
People I know who think it’s important to remove that stuff from drinking or shower water simply use filters. They make shower filters that I think only have to be changed yearly, and for drinking either use a pitcher in the fridge or a faucet filter. Not a big deal.
For what it’s worth–what started this whole thing was developing a rash shortly after moving to Houston (TMI?). I Googled what is in Houston water supply, or some such. The first page I accessed was a long and detailed account of what was wrong with chloramine in drinking/bathing water. Very scientific. Very sober sounding. After reaching the end of the article, I discovered it was from some Houston company that–ta dah–sells whole house filters! Only their filters were capable of filtering out chloramine. Their presentation suggested chloramine would kill you in no time flat. Won’t you join me in a chorus of “Oh, What A Schmuck Am I?”
SeaDragonTattoo: thanx for the tip re shower filters. Had no idea.
Over and out.
Obviously you wouldn’t use sewer water or runoff from a heavy metals mine, but why would using untreated but otherwise clean water from a public spring be a bad idea? You generally boil the wort for an hour or so. Water from a stream or river is considered safe to drink after boiling for 5 minutes (10-15 if you’re feeling paranoid).
I also don’t know of a single homebrewer (and I know many) who boils his tap water before using it…
All surface water sources (including ground water sources classified as ground water under the influence of surface water) and some ground water (though not all and this varies from state to state) are required to provide disinfection of the drinking water. The regulatory requirement for primary disinfection (disinfection of the water leaving the source facility) is that chlorine (either gaseous or bleach or chlorine dioxide) must be used without further justification or if chloramines or ozone are used as a primary disinfectant then additional benchmarks must be established to establish virus removal in addition to the benchmark for Giardia removal. Secondary disinfection is used to protect the water in the distribution system and can use either chlorine, chloramines, ozone or UV.
Many municipal systems use the ammonia-chlorine process as the method for disinfection with the chlorine added in the treatment plant and the ammonia added before entry into the distribution system (though this is an over simplification depending on the amount of nitrogen constituents in the raw water).
The reactions between ammonia (NH[sub]3[/sub] and hypochlorous acid (HOCl - the main species whether from chlorine or bleach addition) are as follows:
[ol]
[li]NH[sub]3[/sub] + HOCl = NH[sub]2[/sub]Cl + H[sub]2[/sub]O {chloramine}[/li][li]NH[sub]2[/sub]Cl + HOCl = NHCl[sub]2[/sub] + H[sub]2[/sub]O {dichloramine}[/li][li]NHCl[sub]2[/sub] + HOCl = NCl[sub]3[/sub] + H[sub]2[/sub]O {trichloramine}[/li][/ol]
Combined chlorine residual is the sum of the mono-, di-, and trichloramine concentrations. Because of a host of reasons the first reaction is the only desired one as di and trichloroamines have issues associated with odors and other undesirable characteristics in drinking water. Again, without going into detail the use of the ammonia-chlorine process is normally done as a part of breakpoint chlorination. The free chlorine residual plus combined residual equals total residual chlorine.
In essence, the USEPA realized that while chlorine (in its many forms) was an important and integral method for achieving the goals of disinfection/inactivation it also had its problems. Namely that chlorine reacted with Natural Organic Matter (NOM) to form haloactetic acids (HAA5) and Total Trihalomethanes (TTHM) both of which have long term effects on humans. Among the reasons that many municipal systems use the ammonia-chlorine (or chloramine) process is to meet the regulations limiting Disinfectants/Disinfection By-products.
Long story short, the practices employed by municipalities to achieve compliance with the Safe Drinking Water Act and also meet the DBPR involve a complex analysis of the mechanisms of each individual source water and what works for City A will rarely work for City B, C, D, etc.
I hope this helps!
This is a perfect example of something we see all the time. Let me state right off that this is NOT meant as an insult to you, burpo. Instead, I think we see this because it’s deeply ingrained human nature. Our brains are fantastic at finding patterns. We see an effect, and we look for a cause. This would be a huge advantage evolutionarily in the wild. We get sick, we notice we tried a new food yesterday, we don’t eat that food any more. The problem is that this system has no way of checking if the patterns we detect are real, and that leads to all kinds of jumps to conclusions. And THAT’S why we need science.
One of these days, I’m going to post a longish essay about how science determines whether an observed connection is actually real or not. I think it would be a useful resource to explain things to people like anti-vaxers and “alternative” medicine folks that wander in from time to time.