Ethyl alcohol is classified as which type of solvent in dehydration, clearing, or infiltration/embedding?

• A. Dehydrant
• B. Clearing
• C. Infiltration/embedding
• D. Dehydrant and clearing aka universal solvent

Answer: (A)

Ethyl alcohol acts as a dehydrant. In tissue processing, dehydration removes water by gradually replacing it with alcohol through increasing concentrations of ethanol. This prepares the tissue for clearing, where a solvent like xylene is used to remove the alcohol and make the tissue receptive to paraffin infiltration. Since alcohol does not dissolve paraffin and is not used to clear or infiltrate, its role here is specifically to remove water during dehydration.