[Development of alternative to animal experiment in evaluation of skin irritation caused by alcohol-based hand rubs].

Alcohol-based hand rubs are widely used for infection control in clinical practice. However, it is known that frequent use of the alcohol-based hand rubs may cause skin irritation. To predict the skin irritation in human, animal experiments are quite useful. Especially, the Draize Test using rabbits is suitable for this purpose because their skin is highly sensitive. On the other hand, the development of alternative to animal experiments is important not only from the viewpoint of ethical aspects but also from the efficient research and development. Reconstructed human epidermis (RhE) was developed as a human skin equivalent model in vitro, and has been applied to the evaluation of skin irritation. But the RhE has not been utilized for the evaluation of alcohol-based hand rubs because of the high skin permeability and cytotoxicity of alcohols. The aim of this study was to develop a new method using the RhE in evaluation of skin irritation caused by alcohol-based hand rubs. The authors propose an experimental technique named "Skin model blowing method (SMBM)" consisting of the sequential procedure as follows; applying small amount of testing sample on RhE, blow-dry, post incubation, and cell viability measurement. According to the SMBM, the skin irritation caused by alcohol-based hand rubs could be evaluated under the similar condition of their actual use. It was found that a high correlation existed between the cell viability obtained from SMBM and the skin irritation index in rabbit which had been reported previously.