Background: Acetic acid has been used for many decades to clean and disinfect surfaces in the household. Disinfection in the household is particularly important for the group of YOPI (young, old, pregnant, immunocompromised), as they represent a risk group. In addition to known pathogens, viruses are also becoming a major problem not only for this group, but due to the new Sars-CoV-2 virus all people are affected. The aim of this study is to show that acetic acid has a disinfecting effect against certain microorganisms and is able to destroy certain viruses. Furthermore, a disinfecting effect of laundry in a simulated washing cycle will be investigated.
Results: At a concentration of 10% and an addition of 1.5% citric acid according to the specifications of DIN EN 1040 and DIN EN 1275, acetic acid showed a reduction of > 5-log steps in the following microorganisms: P. aeruginosa, E. coli, S. aureus, L. monocytogenes, K. pneumoniae, E. hirae and A. brasiliensis. For MRSA a logarithmic reduction of 3.19 was obtained. The results of the test according to DIN EN 13697 showed a complete reduction (> 5-log steps) for P. aeruginosa, E. coli, S. aureus, E. hirae, A. brasiliensis and C. albicans already from a acetic acid concentration of 5%. The results of the tests according to DIN EN 14476 and DIN EN 16777 showed a reduction of ≥ 4-log-steps against the Modified Vaccinia virus Ankara (MVA) for the tested acetic acid concentrations of 5%, 7.5% and 10%. This means a virucidal effect of 5% acetic acid. Furthermore, the results showed that acetic acid does not have a sufficient disinfecting effect on microorganisms in a dosage that is commonly used for cleaning. However, this can be achieved by increasing the concentration of acetic acid used, especially when combined with citric acid.
Conclusions: Our results show a disinfecting effect of acetic acid in a concentration of 10% and an addition of 1.5% citric acid against a variety of microorganisms. A virucidal effect against enveloped viruses could also be proven. Furthermore, the results showed a disinfecting effect of acetic acid in domestic laundry procedures.