[pct-l] Aquamira info

[Ikem Freeman]

I love it! Andy says:

"Otherwise, just use the (water) treatment of your choice, and quit your
worrying, you're going
to make yourself sick!!"

Reminds me of the most dangerous part of my '08 PCT trek ... the 60 minute
drive on Interstate 5 to the Portland Airport to a catch a flight!

O. Ikem Sofar

On Thu, Mar 5, 2009 at 2:58 PM, Andrew Jones <a.freddy.j at gmail.com> wrote:

> You guys were asking for a chemist's opinion. I'm a chemist at a brewery,
> where we use chlorine dioxide as a surface sanitizer, so here we go.
>
> First off, the shelf life of Aquamira. Sodium Chlorite solution (solution
> A,
> I believe) is very stable as long as it's kept cool and away from light.
> I'm
> not technically advising you to use Aquamira past its expiration date to
> absolve my liability, but I can't think of a reason for it to go bad as
> long
> as it's kept cool and relatively dark (I think it's in a solid white
> plastic
> bottle...?).
>
> After mixing the solutions, the pH should drop to between 4-5, and the
> chlorite will start to convert to chlorine dioxide. It is this molecule
> that
> has sanitizing activity, NOT free oxygen. *This is a gas in solution*, so
> the life of the activated solution is somewhat short (a matter of a couple
> hours, depending on concentration). For anybody that cares, what's actually
> happening is an equalibrium is established between the chlorite and
> chlorine
> dioxide. As the chlorine dioxide leaves the water (remember, it's a gas),
> more of the chlorite is converted until it's gone. This gives the solution
> moderate stability, but as I said, only for a few hours, after which the
> concentration of both chemicals drops to a non-active level. THE BEST
> OPTION
> IS TO USE IT IMMEDIATELY AFTER ACTIVATION! ONLY THEN CAN YOU BE POSITIVE
> THE
> SOLUTION HAS THE CONCENTRATION INTENDED FOR USE BY THE MANUFACTURER.
>
> As for homemade kits, if you're a chemist and you know what you're doing,
> feel free to go ahead, at your own risk. I will not give advice on how to
> do
> this for liability's sake, but keep in mind the activation solution must be
> between 4-5 pH, and I would only trust high quality pH strips to check this
> unless I was VERY confident in my drop size measurement method. These run
> $40 per 100, so you've just increased your cost 40 cents per treatment.
> Hopefully I've talked you all out of this....
>
> And with all treatment options, remember, none are foolproof. Measuring
> treatments by drop size is inaccurate, iodine tablets decompose over time,
> no chemical treatment can really penetrate solid particles unless given
> hours or days to do so, UV-C lights have the same problem with particles,
> and filters honestly are only as good as their o-rings or membrane
> construction (also Cryptosporidium, for example, is small enough to
> penetrate some ceramic membranes). The ONLY 100% reliable treatment option
> is boiling for at least 3 minutes! Not gonna happen! So what cold
> treatments
> do is REDUCE the bacteria/viruses to a level that can be withstood by an
> average human immune system. If you have a compromised immune system, I
> would recommend using more than one treatment method every time. Otherwise,
> just use the treatment of your choice, and quit your worrying, you're going
> to make yourself sick!!
>
> Andy
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