Appendix III: Classes of Disinfectants and Characteristics

Safety > Biosafety

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Hypochlorities (Chlorox, Presept)

• Good general purpose disinfectant but corrosive against metal and should not be used on metal surfaces (i.e. stainless steel counters, centrifuges)
• Active against viruses
• Avoid contact with formaldehyde because the two compounds react together to produce carcinogenic products.
• Must be made fresh daily because they are readily inactivated by organic matter.
• Concentrations used

1. 1000 ppm for general use surface disinfection

2. 2500 ppm in discard pipette washing containers

3. 10,000 ppm for tissue culture waste and spillages

Phenolics (e.g. Sudol, Hycolin)

• Not active against viruses
• Remains active in the presence of organic matter

Alcohol (e.g. ethanol, isopropanol)

• Effective against bacteria.
• Ethanol is effective against most viruses but not non-enveloped viruses. Isopropanol is not effective against viruses.
• Effective concentrations

1. Ethanol 70%

2. Isopropanol 60-70%

Aldehydes (e.g. glutaraldehyde formaldehyde)

• Major disadvantage is their toxicity to humans
• Glutaraldehyde can be used when hypochlorites are not suitable (stainless steel sinks)

Quaternary Ammonium Compounds (e.g. Bacdown)

• Effective against gram positive and gram negative bacteria and lipophilic viruses
• Ineffective against spores
• Readily inactivated by organic matter.
• Working concentrations are dilute enough to be less irritating and toxic to humans.

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