Sporicidal activity of an improved iodide formulation and suggestions regarding the biological safety cabinet.
The sporicidal activity of an improved iodide formulation based on a previously reported agent (Kida et al., 2004, tentatively designated as the KMT reagent) which is composed of 50 mM EDTA-2Na, 50 mM ferric chloride hexahydrate (FeCl3.6H2O), 50 mM potassium iodide (KI) and 50% ethanol in 0.85% NaCl solution at pH 0.3 with hydrochloric acid, was examined in the liquid and vapor phases. The improved iodide formulation subject to distillation (tentatively designated as the distilled KMT reagent: pH around 3) showed comparable sporicidal activity with the KMT reagent. As for the dilution effect, dilution at 1:2 showed more potent sporicidal activity than the undiluted one. It achieved complete disinfection with a treatment for 5 min at 20 degrees C and for 60 min at 5 degrees C. Even at a ratio of 1:100, the dilutions showed significant sporicidal activities at 37 degrees C. The experiment on the disinfection of the biological safety cabinet (Class II type A) as a practical possibility showed that pretreatment with 400 ml of water vapor treatment, and a mixture of 300 ml of this reagent and 150 ml of water in vapor phase achieved complete disinfection after a 24 h-decontamination process. The distilled KMT reagent may be useful for disinfecting against various contaminated materials and sites in both the liquid phase and vapor phase.
Kida
Nori
N
Niigata Quarantine Station, Ministry of Health, Labour and Welfare, 1-5-4, Ryugashima, Chuo-ku, Niigata, Niigata 950-0072, Japan. kida-nori@keneki.go.jp
D001412:Bacillus subtilis / Q000187:drug effects; D002626:Chemistry, Pharmaceutical; D002712:Chlorides; D003343:Corrosion; D004202:Disinfectants / Q000737:chemistry / Q000494:pharmacology*; D004492:Edetic Acid; D000431:Ethanol; D005290:Ferric Compounds; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007454:Iodides / Q000737:chemistry / Q000494:pharmacology*; D007753:Laboratories; D011193:Potassium Iodide; D012449:Safety; D013171:Spores, Bacterial / Q000187:drug effects*; D014691:Ventilation; D014835:Volatilization
D002712:Chlorides; D004202:Disinfectants; D005290:Ferric Compounds; D007202:Indicators and Reagents; D007454:Iodides; D011193:Potassium Iodide; D000431:Ethanol; D004492:Edetic Acid; C024555:ferric chloride