Page 136 - The Veterinary Laboratory and Field Manual 3rd Edition

The selection, use, maintenance and quality control of laboratory equipment and supplies 105

Disinfection • have as broad a spectrum of action as possible,
that is, be able to kill several types of pathogens
Disinfection can be achieved with chemical (for • need only a short exposure time
example, alcohol) or physical (for example, tem- • not be susceptible to any (or to only little)
perature) methods.
loss of efficacy in the presence of proteins
• not have any (or only very little) unpleasant
cHEMIcaL dISInFEctIon (tabLE 2.5) odour
In chemical disinfection microorganisms are • not cause any (or only very little) irritation to
killed by certain chemicals. To that effect, sev- skin or mucous membranes
eral chemical disinfectants are available. To • have a high material compatibility profile
be deemed suitable for that purpose, they • be environmentally friendly
should:
• be economical.

Table 2.5 Classes of active substances used in chemical disinfectants.

Active Spectrum of Fields of Pros Cons
substance action application
Aldehydes Covers virtually Surfaces Biodegradeable Unpleasant odour
formaldehyde the entire Instruments Low use Allergenic
glutaraldehyde spectrum concentration
glyoxal
Alcohols Bactericidal Hands Rapid onset of Risk of fire and
ethanol Fungicidal Surfaces action explosion if used
n-propanol Virucidal to an Biodegradeable to disinfect large
isopropanol extent Dries quickly surfaces
Generally Skin-degreasing
good material effect
compatibility
Quaternary Depending on Instruments Sustained effect Adversely affected if
ammonium substance Hands Odourless used in combination
compounds bactericidal with anionic
(QUATs) fungicidal surfactants (soap
effects)
Halogens Covers virtually Instruments Rapid onset of Poor biodegradability
sodium the entire Hands action profile
hypochlorite spectrum (mucous Corrosive to metals
povidone-iodine membranes) Irritant to mucous
membranes
Per compounds Covers virtually Instruments Rapid onset of Unstable
hydrogen the entire Mucous action
peroxide spectrum membranes Biodegradable
peracetic acid Water
Phenols Bactericidal Surfaces Few protein Poor biodegradability
and phenol Virucidal to an Instruments effects profile
derivatives extent Good cleaning Hazardous to health
performance

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