[pct-l] Aqua Mira Question

[brick@fastpack.com (Brick Robbins)]

At 04:49 PM 12/9/02, Susan Faidley wrote:
>Does anyone know if aqua mira alone is not supposed to take
>care of Giardia?

If you do a search in the list archives you will find lots of stuff about
this.....

Aqua Mira is Chlorine Dioxide. Chlorine is not considered adequate to kill
cystic protazoa, like Giardia. Iodine is better, but you should wait an hour.

The Center for Disease Control says (In part)

== begin copy===
The effect of chemical disinfection, such as chlorine, on the viability of
Giardia cysts is an even more complex issue. It is clear from the number of
waterborne outbreaks of Giardia that have occurred in communities where
chlorine was employed as a disinfectant that the amount of chlorine used
routinely for municipal water treatment is not effective against Giardia
cysts. These observations have been confirmed in the laboratory under
experimental conditions (25,26,27). This does not mean, however, that
chlorine does not work at all. It does work under certain favorable
conditions.

<snip>

Chemical Disinfection {for Water Disinfection in the Out-of-Doors}

  Disinfection of water with chlorine or iodine is considered less reliable
than boiling for killing Giardia. However, it is recognized that boiling
drinking water is not practical under many circumstances. Therefore, when
one cannot boil drinking water, chemical disinfectants such as iodine or
chlorine should be used. This will provide some protection against Giardia
and will destroy most bacteria and viruses that cause illness. Iodine or
chlorine concentrations of 8 mg/liter (8ppm) with a minimum contact time of
30 minutes are recommended. If the water is cold (less than 10 deg C or 5O
deg F) we suggest a minimum contact time of 60 minutes. If you have a
choice of disinfectants, use iodine. Iodine's disinfectant activity is less
likely to be reduced by unfavorable water conditions, such as dissolved
organic material in water or by water with a high pH, than chlorine.
====end copy===

reference
http://home.earthlink.net/~alanwdove/Water.html
--
Brick Robbins                       mailto:brick@fastpack.com