Picture taken from WebMD
Skin is our largest organ. Its area is about 20 square feet. It is our border with the environment. Without it, we would not be able to live. Our heating and cooling functions, water evaporation rate would be irreparably disrupted.
Bacterial invasion would soon overpower us and we would die.
Organ skin is the most accessible one
Luckily, our largest organ, organ skin is also the most accessible one. We do not have to eat large amounts of nutrients. That way they spread all over our body and become diluted. So only a small proportion comes into our skin. We can treat our largest organ directly. Because our skin is our border with environment it is often exposed to all kinds of chemicals. Chemicals can be absorbed either through hair follicles, glands or epidermis. Most of the absorption is happening through epidermis. After passing seven layers of epidermal cells, chemicals are in dermis. They can enter blood from there or lymph circulation, and spread systemically. Outermost layer of epidermis – stratum corneum, primarily is composed of cholesterols, and ceramides. This is the biggest obstacle for chemicals. Fat soluble chemicals can more easily penetrate this obstacle and get into the circulation. One there, they can cause positive or negative systemic effects.