Interaction of surfactants with skin

Different substrates have, however, been used in the literature to predict the interaction of surfactants with skin keratin they are, for instance, wool fibers, human hairs, and callus powder [2,3]. It has been reported [4] that these keratinous substrates from different origins are able to rank surfactant binding similar to skin keratin m vivo [3,5], although results are not quantitative. 

Providing that there is no undue risk to the subjects and that the studies are performed according to a fully ethical approach and by appropriate personnel, the interaction of surfactants with skin can be investigated on human volunteers. 

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