Re: [pct-l] Giardia, Chlorine and Iodine

[Brick Robbins <brick@fastpack.com>]

At 12:36 PM 8/23/99 -0700, Carolyn M Eddy wrote:

>If you read the CDC article they do not say bleach is ineffective.

Neither did I. I used the direct quote "chlorine concentration that would
be safe yet
effective against Giardia cysts under all water conditions."

This is a question of determining an adequate concentration and time to be
effective in all situations. The CDC seems to think this is a difficult
problem.

Bleach will kill just about anything. When the Russians wanted to kill
their stockpile of Anthrax, they used bleach.


>The 10% bleach solution I referred to is actually less than what you are
>using in your water with a chlorine system.
>It will not kill you as it is
>neutralized with hydrogen peroxide. If it did I'd already be dead.

I took "10% bleach solution" be 10% by weight sodium hypochlorite, which is
about twice the strength of household bleach, and that will kill you dead.
You must be refering to some different measure.

>And no I don't have subclinical giardia. I checked. And, I have had it, from
>the same water sources I'm currently using, using a filter.

I'm not saying you do or don't have an infection, but stool sample tests
for Giardia are notorius for giving false negatives. They can proove DO
have an infection but a negative result doesn't proove you DON'T have one. 

It could just be that your immune system has developed a resistance from
past exposure. Mine did.

I'm not trying to say that bleach is bad, just that there are other methods
of purification that are considered better. 

-B
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