The Minimal “Chlorine Death Points” of Bacteria—I. Vegetative Forms

Influence of Alkalies on Available Chlorine and on Germicidal Effect of Sodium Hypochlorite in Presence of Organic Matter as Ice-Cream Mix

“…The second part of the work is a study of the sterilizing efficiency of chlorine alone and in combination with sodium carbonate, trisodium phosphate, and sodium hydroxide with and without ice-cream mix at 50°C ., using Escherichia coli as the test organism, since this organism has been shown (18) to be resistant to free chlorine.…”

The mycoplasmacidal properties of sodium hypochlorite

“…At, or close to, pH 7 it is effective in micromolar concentrations (Tonney, Greer & Danforth, 1928;Tonney, Greer & Liebig, 1930;Kelly & Sanderson, 1958;Scarpino et al 1972;Englebrecht et al 1980;Harakeh & Butler, 1984), provided that the water is free from ammonia and organic compounds which contain nitrogen; in the presence of these compounds, however, the effectiveness of chlorine is diminished due to reactions yielding chloramines or other chloro-organic compounds, which are not potent biocides (Heicken, 1956;Dychdala, 1977).…”

“…1980;Scarpino et al 1972) bacterial vegetative cells and spores (e.g. Tonney, Greer & Danforth, 1928;Tonney, Greer & Liebig, 1930;Foegeding, 1983), fungal vegetative cells and spores (Haas & Englebrecht, 1980 & Van de Voorde, 1976;Cursons, Brown & Keys, 1980) and algae (Kott, 1979), little is known about the conditions for mycoplasmacidal activity.…”

Properties and treatment of pond water supplies

“…In general, studies (12,79,83) conducted to determine the comparative resistance of pathogenic bacteria and E. coli to chlorine disinfection have indicated that the destruction of E, coli was a good index of chlorination effectiveness against bacteria. However, other investigations showed that E. coli had a markedly lower resistance to chlorine disinfection than some pathogenic bacteria {$b)» Results of recent studies (18, $1, ï>9* 81t), particularly those pertaining to the inactivation of pathogenic viruses, indicate that the E. coli index for water purity and normal chlorination procedure for the disinfection of small water supplies are inadequate to assure a safe water supply.…”