Using aniline derivatives on facial hair can lead to damage of which area?

Using aniline derivatives on facial hair can lead to damage to the lips and nostrils because these areas are particularly sensitive and more prone to irritation. Aniline derivatives, commonly found in hair dyes, can cause allergic reactions or chemical burns if they come into contact with delicate skin. The lips and nostrils have thinner skin compared to other facial areas, making them more susceptible to adverse reactions from these chemicals. Additionally, applying such products near these sensitive areas increases the risk of exposure, hence the potential for irritation or allergies is heightened.

In contrast, areas such as the scalp, cheeks, and forehead, while also sensitive, typically have a higher tolerance to such products due to their thicker skin. However, the increased risk in the lips and nostrils emphasizes the importance of caution when using aniline derivatives in close proximity to these vulnerable areas.