Skin is the body's protective organ, protecting the body from harmful substances in the external environment, while preventing the loss of nutrients, electrolytes and water in the body. The protective functions of the skin are mainly manifested in the following aspects:
(1) chemical substances invasion.
The skin mainly protects against chemical substances in the stratum corneum, which is tightly structured and forms a complete semi-permeable membrane. Except for sweat pipes, there are no large pores.