Chlorine disinfection

Enigl enigl at
Mon Sep 15 22:16:01 EST 1997

<<  in order to kill amoeba?  
Iodine kills amoeba NOT chlorine. 
What is the dilution to achieve 
high level sterilization (kills spores)? 
Chlorine needs to be concentrated much higher than only 5.25% to kill
spores.  Glutaraldehyde is used to kill spores . . . NOT  chlorine.   High
level sterilization can NOT be achieved with chlorine bleach.  That's why
it is not used in the pharmaceutical industry for sterilization.  Chlorine
IS used for domestic water systems to merely slow bacterial growth (but not
protozoa as you suggest)  and chlorine is used to sanitize (NOT sterilize)
floors. The floors most be very clean because dirt stops chlorine (bleach)
from killing anything. 
<<I have heard that a certain dilution is best, and above that it is not as 
effective. Is this correct, or if not, what leeway do I have? 

That is correct for isopropyl alcohol (70% kills more than 90%) . . . but
NOT chlorine., where higher concentration is more effective.  Don't expect
bleach to kill amoeba or spores.
<<Thanks very much. Please email me.  
You wouldn't happen to be Katherine Burslem?  If so expect an answer to
you previous question early next week. 

Davin C. Enigl,  MEAS, Master of Environmental Arts and Sciences 
President-Microbiologist, HACCP Validations (tm).  Quality Assurance,
Quality Control, Research and Development

Co-author (with Kent M. Sorrells), Water Activity and Self-Preserving
Formulas, In:  _Preservative-Free and Self-Preserving Cosmetics and Drugs_,
Kabara and Orth, eds.  Copyright 1997,  
Marcel-Dekker, ISBN 0-8247-9366-8, Telephone: 1-800-228-1160

Microbiology Services for:  Biotechnology, Cosmetics, Foods, and

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September 13, 1997
1:02 pm PACIFIC

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