What is the primary function of the skin regarding chemical absorption?

The primary function of the skin regarding chemical absorption is the absorption of essential chemicals. The skin acts as a barrier that can selectively absorb certain substances while preventing the passage of others. Factors such as molecular size, solubility, and the health of the skin determine what can be absorbed. For instance, certain skincare products are formulated to include ingredients that can penetrate the skin's outer layers, providing hydration and nutrients to the deeper skin structures. This selectivity is important for maintaining skin health and ensuring that beneficial compounds can enter while harmful substances are kept out.

In contrast, while the skin does prevent the absorption of many harmful chemicals, this does not serve as its primary function. The role of filtering toxins from the blood is primarily performed by organs like the liver and kidneys, not the skin. Allowing moisture to escape can occur as a natural function, but it does not relate to chemical absorption in a direct or primary manner.