Ingredient
p-Phenylenediamine (PPD)
What is p-Phenylenediamine (PPD)?
P-Phenylenediamine (PPD) is a chemical compound commonly used in the production of hair dyes. It is an organic compound derived from aniline and belongs to the aromatic amine family.
PPD is favored in hair dyes because it provides long-lasting color and is effective in covering gray hair. However, the health evidence indicates that PPD can cause allergic reactions in some individuals. It has been associated with skin irritation and dermatitis when used in high concentrations.
When you see PPD on a label, especially in products like hair dyes, it's important to be aware of the potential for allergic reactions. Performing a patch test before full application can help identify allergies to this compound.
Commonly found in: Hair dyes, Henna products
What to watch
- Known to cause allergic skin reactions and dermatitis in sensitive individuals.
The FDA regulates the use of PPD in hair dyes but advises caution due to potential allergic reactions.
Research indicates a risk of allergic reactions, with some studies highlighting the need for caution due to sensitivity in some individuals.
PPD is a synthetic compound and not derived from animals, typically considered vegan.
Sources: Hair Dye Safety
Scout's take
PPD is one of the most common causes of severe allergic contact dermatitis in cosmetic chemistry; the FDA, EU SCCS, and dermatology societies have repeatedly flagged it. Sensitization can be permanent and reactions can escalate from mild itching to severe facial swelling and life-threatening anaphylaxis with repeated use. It also undergoes oxidative reactions in the dye process that can generate additional reactive intermediates.
Found in 5 products
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