Addition: Chlorine Bleach (and Peroxide)
- Subject: Addition: Chlorine Bleach (and Peroxide)
- From: Ted.Held@hstna.com
- Date: Thu, 13 Dec 2001 09:45:45 -0600 (CST)
Oops. And when bleach breaks down there is also some residual alkali
(sodium hydroxide, caustic soda) left over. This means the pH will be basic
(probably 10 or thereabouts).
----- Forwarded by Ted Held/PA/Henkel Americas on 12/13/01 09:36 AM -----
12/13/01 08:29 cc:
AM Fax to:
Subject: Chlorine Bleach (and Peroxide)
(Document link: Ted Held)
Here are a few comments about chlorine bleach (sodium hypochlorite):
Relatively non poisonous - provided you don't acidify it (as by adding
vinegar), which will release actual chlorine gas, a decidely toxic
material. See later comments.
-Compared to complex organics, less persistent
True. But many of the commercial microbicides are actually not very
persistent as was the case with early pesticides. I think current
microbicides are good when used as directed.
-Not absorbed by tissues (the prize plant or our skin and lungs)
Will be absorbed by tissues as you might notice if you use bleach without
gloves. That offensive (to me) smell that hangs on your exposed skin is
evidence of lingering chlorine absorption (and tissue degradation).
-Breaks down into water and ordinary salt
Yes, once its oxidizing work is complete.
-Even cheaper than hydrogen peroxide
Pound for pound, bleach is less expensive than peroxide as a microbicide.
On the other hand, we in the hobby are not in the business of mass killing
where the cost is really a factor. Bleach happens to be handy, however,
meaning that you have a disinfectant in the house whenever you need it.
-Does not oxidize living tissue
Does, in fact, oxidize living tissue. That is the way it kills. Bacteria
and fungi are oxidized to death. It will oxidize your epidermis if not
protected. Not advisable to leave it in contact with skin for any length of
-As for friendly microorganisms, they can repopulate the sanitized areas
rapidly by spreading from the healthy surface of a tuber, or from healthy
True, provided the residual bleach is rinsed away and a healthy inoculate
-Very low concentrations will kill germs
True. Bleach probably has ten times the killing power compared with an
equivalent of peroxide. Incidently, will increase its killing power
dramatically if the pH is lowered, making chlorine poison gas more readily
available. Acidification by non-professionals is not advised.
-You don't have to wear a respirator or chase away the kids and pets.
Some people don't like the smell of bleach. I find it cloying and choking
when used in a confined space. If you make a little dilution in a bucket
for washing off tubers all you really need is a modicum of air circulation.
If you acidify it, chlorine gas is really gross and can actually kill you.
Take my word for it.