[Estimation of the activity of an antiseptic agent on skin microbial flora under various conditions]

The bacterial flora of the skin of the fore-arm was studied in fifteen normal subjects by a modified Williamson and Kligman technique. The quantitative results were in agreement with those found in other laboratories which indicates the reproducibility of the method. The action of an antiseptic containing 0.5 p. cent of benzalkonium chloride was studied under three conditions or single application of the antiseptic for five consecutive days and for 24 hours after the application of an occlusive dressing. The bacterial flora of the skin showed marked quantitative variations from one subject to another and, in the same subject, from one time to another. Evaluation of the activity of an antiseptic should take into consideration these physiological variations and also various conditions of use in practice. Are discussed also the factors leading to standardisation of the methods and the criteria of evaluation of the activity of antiseptics on the skin.