Water and alcohol cannot be effectively absorbed through the skin via osmosis into the bloodstream due to the skin's protective barrier. While some chemicals can penetrate the skin, their ability to do so often depends on their molecular characteristics. Dimethyl sulfoxide (DMSO) is highlighted for its unique properties, including its polar nature and small structure, which allow it to penetrate living tissues without significant damage. In contrast, small hydrophobic molecules and certain polar solvents like methanol can also penetrate the skin, but larger molecules like water and alcohol do not easily enter the bloodstream. The discussion emphasizes that if substances could easily seep into the body, it could pose serious health risks.
