Alaska Hairdresser and Barber Certification Practice Exam

What is a common cause of allergic reactions associated with hairdressing products?

1. Aloe Vera

2. Para-phenylenediamine (PPD)

3. Silicone

4. Phenoxyethanol

The correct answer is: Para-phenylenediamine (PPD)

The common cause of allergic reactions associated with hairdressing products is para-phenylenediamine (PPD). PPD is a chemical compound frequently used in hair dyes, particularly in permanent hair coloring products. It is known for its ability to bind to hair fibers and produce long-lasting, vibrant color. However, PPD can also lead to sensitization and allergic reactions in some individuals, resulting in symptoms such as redness, itching, and swelling of the scalp and surrounding areas. The concern with PPD arises because it can penetrate the skin barrier, prompting the body’s immune system to react to it as a foreign substance. As a result, hairdressers need to be vigilant about performing patch tests prior to applying hair color containing PPD to ensure that clients do not have an existing sensitivity. Contrasting with this, other ingredients mentioned—like aloe vera, silicone, and phenoxyethanol—tend to have lower risk profiles for allergic reactions. Aloe vera is often used for its soothing properties and is less likely to cause irritation. Silicone is used for its conditioning and shine-enhancing benefits, and while it can sometimes cause build-up, it does not typically lead to allergic reactions. Phenoxyethanol, a common preservative in cosmetic