Which formulation is likely to offer the greatest possibility of dermal absorption?

Oil soluble formulations are likely to offer the greatest possibility of dermal absorption due to their ability to easily penetrate the lipid layers of the skin. The skin acts as a barrier primarily composed of fats and oils, which means that substances that are also lipid-friendly can pass through more readily. Oil-soluble compounds are structurally similar to the components of the skin, allowing for higher absorption rates.

These types of formulations often have smaller molecular sizes and can dissolve in the oil present in skin cells, facilitating their entry into the bloodstream. In contrast, other formulations, like water-soluble or granular formulations, may not penetrate the skin as effectively because of the hydrophilic nature of their active ingredients and formulation composition. Emulsifiable concentrate formulations may allow for some level of absorption, but their efficacy is typically less than that of oil-soluble products when it comes to dermal penetration.