Hydrogen peroxide and peracetic acid are not appropriate if blood is present. Hypochlorites are sporicidal but are rapidly neutralized by organic matter and, therefore, while good for items like laboratory surfaces (not wooden ones) or glassware, or for water treatment, are unsuitable for disinfecting most environmental sites or materials. Chlorine dioxide was the alternative chosen in the USA for decontamination of rooms following the anthrax letter events of 2001. The principal disinfecting agents for destruction of anthrax spores are formaldehyde, glutaraldehyde (at pH 8.0–8.5), hydrogen peroxide and peracetic acid ( Dietz & Böhm, 1980 Böhm, 1990). anthracis, and procedures that are both practical and effective have yet to be worked out for numerous situations. Lists of approved disinfectants published periodically in some countries may be misleading when selecting the sporicidal disinfectant to use for B. As noted in Annex 1, section 7.9, UV irradiation should not be relied on alone for decontamination, but should be used in conjunction with wiping down items to be decontaminated with hypochlorite or possibly formalin. For certain materials or animal by-products, irradiation with gamma rays or particle bombardment may be appropriate (see 6.6 below). If heat treatment or incineration of the contaminated material is possible, this should be done in preference to chemical decontamination and disinfection. The results are that (i) only a few fairly formidable chemicals and procedures are capable of reliably killing anthrax spores, and (ii) information on the sporicidal activities of disinfectants, fumigants, and disinfection and fumigation procedures based on other Bacillus species should be viewed with caution. anthracis is essentially an obligate pathogen and depends for the continued existence of the species on the survival of the spores in the environment between infections of successive hosts, it appears to produce particularly tenaceous spores. Choice of disinfectants, fumigants or procedures In the case of UV irradiation, care should be taken to protect the eyes and not to expose eyes or skin to direct UV light sources.įurther cautions are given as appropriate in the sections that follow.ġ.2. Irradiation by gamma ray or particle bombardment should only be done by properly trained persons in properly monitored facilities. Respirators should be fitted and tested by qualified personnel, and users of respirators should be trained in their correct use by qualified personnel. Peroxides may be explosive under certain circumstances.Īppropriate (chemical) respirators should be worn by personnel disinfecting or fumigating closed spaces (rooms, stables, etc.) and when opening up such places to ventilate them at the end of the disinfection or fumigation procedure. All containers of disinfectants should be properly and accurately labelled as to their contents. Clean water should be at hand for immediate washing or showering in the event of an accident while handling concentrated disinfectants. In the case of fumigation, the work should only be carried out by trained professionals with appropriate protective clothing and breathing apparatus.Īttention is drawn to the importance of handling the concentrated liquid disinfectants referred to with caution, using gloves and aprons or overalls and goggles or eye shields to prevent contact with skin or eyes. Precautions, therefore, should be taken not to get these on skin or into the eyes or, especially with the aldehydes, not to inhale them. At the concentrations necessary to be effective as sporicides, these are potentially hazardous to human health if handled incorrectly. The most widely used sporicides are chlorine (as in hypochlorite solutions or “bleach”) and formaldehyde, with some use being made of hydrogen peroxide and other oxidizing agents, or glutaraldehyde. It follows, therefore, that chemicals and procedures which can kill spores are necessarily highly lethal to less hardy cells, including those in human, animal and plant tissues. levels of heat, radiation, desiccation, acidity, alkalinity and other chemical and physical conditions) that would rapidly kill other forms of life. Bacterial spores are designed by nature to survive in the face of adverse conditions (i.e.
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