Appendix III: Classes of Disinfectants and Characteristics

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
    • 1000 ppm for general use surface disinfection
    • 2500 ppm in discard pipette washing containers
    • 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
    • Ethanol 70%
    • 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.