Sporicidal activity of tea tree oil

These findings emphasise the fact that it is necessary to assess final formulations rather than the active component by itself as excipients may interfere with the activity. The alcohol-containing AHSW and AHR did not demonstrate any sporicidal properties, confirming previous studies showing that alcohol is not sporicidal and suggesting no synergy between TTO and alcohol against spores. Hence these should not be used for hand hygiene or surface decontamination if spores are involved. Further studies should be carried out to investigate the potential sporicidal activity of TTO directly on human skin in vivo with volunteers andlor by using an 'ex vivo' test that uses freshly excised human skin and which would allow testing of any biocide as well as any spore-forming bacterial strain, including pathogens.