New Hampshire Barber Practice Exam 2026 - Free Barber Practice Questions and Study Guide

PPD, or para-phenylenediamine, is a chemical commonly used in hair dyes and is known to be a potential allergen for some individuals. This ingredient is often added to hair color formulations to enhance color intensity and longevity. However, it is recognized for its ability to provoke allergic reactions in certain people, manifesting as contact dermatitis, itching, and redness at the application site or in more severe cases, systemic reactions.

In contrast, the other options listed do not have the same level of association with allergic reactions. Aloe Vera is typically used for its soothing properties and is generally considered safe for most skin types. Talc is commonly used as a filler and does not usually produce allergic reactions, though it has its own health concerns unrelated to allergies. Mineral oil serves as a moisturizing agent and is also considered hypoallergenic for the most part. This distinction helps to clarify why PPD is singled out as a known allergen within hair dye formulations.