|MadSci Network: Chemistry|
You don't say which position your father is taking. If you want to prove your dad wrong, I hope you said that some chemicals absolutely can absorb into the skin. This is called dermal exposure and can lead to health problems if enough of the chemical can enter the body. For example, one concern is dermal exposure of workers to pesticides during mixing and application of these materials. Some pesticide formulations are especially hazardous if they are both toxic and contain fat-soluble solvents, such as kerosene, xylene and other petroleum products that make it easier for the pesticide to penetrate the skin. This is why it is very important to wear protective clothing when using these chemicals.
So, although the skin is a good barrier to many chemicals, some can penetrate and cause illness. I hope this helps you, good luck.
Hazardous Substances Scientist
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