Final answer:
a) Oil-based pesticides are most readily absorbed by the skin due to their solubility in oily substances, which mirrors the composition of skin cells.
Step-by-step explanation:
The question "which pesticides are most readily absorbed by the skin?" concerns the properties of pesticides and how they are absorbed into organic systems, such as the human skin or animal tissue. Given the information provided, the answer would be oil-based pesticides.
These pesticides are more readily absorbed by the skin because they are soluble in oily substances, much like the lipids found in skin cells.
As discussed, substances that are more soluble in oil than in water will be preferentially taken up by organisms. In contrast, water-soluble substances or those in forms such as wettable powders or certain formulations may not penetrate the skin as effectively as those that are oil-soluble.
When it comes to pesticides being absorbed by the skin, the most readily absorbed type is oil. This is because many pesticides are more soluble in oil than in water.
For example, if a pesticide residue is more soluble in oil than in water, it will be preferentially taken up and retained by marine organisms that contain more oil-like substances.
This mechanism is also responsible for the biomagnification of certain pesticide residues within the food chain. Other types of pesticides, such as water-soluble and wettable powder formulations, are less readily absorbed by the skin.