Ingredient

p-Phenylenediamine (PPD)

High risk

FunctionOxidative dye — common allergen

What it is — p-Phenylenediamine (PPD) is a primary oxidative hair dye that develops permanent colour once oxidized.

What it does — Used within permanent hair-color systems, it reacts during oxidation to form and lock in the finished shade.

Typical use — Found in permanent and oxidative hair-color products, not in leave-on skincare.

Who it suits / good to know — Relevant to hair coloring rather than skincare routines. It is one of the best-known hair-dye allergens, so anyone with a history of reacting to hair dye should be especially cautious.

Safety — DHALIORA grades it high risk in its EWG-style review: it is a potent skin sensitizer and a leading cause of hair-dye allergic contact dermatitis (named a Contact Allergen of the Year in 2006), and hazard databases rate it a high concern. This is general information, not medical advice. A patch/allergy test before each use is standard for oxidative hair color; discontinue immediately if a reaction occurs.

Why we grade it High: High risk — a potent skin sensitizer and a leading cause of hair-dye allergic contact dermatitis (ACDS Allergen of the Year 2006); EWG rates it a high hazard.
Cross-reference

Found in these DHALIORA products

Found in 1 DHALIORA product

GDS Hair Dye Shampoo — Grey Coverage in 3 Minutes GDS Hair Dye Shampoo — Grey Coverage in 3 MinutesScreening 8.6
How grades are set — Risk reflects our own reading of publicly available safety data, an EWG-style reading shown at the worst-case grade we've assigned this ingredient across products. It isn't a third party's proprietary score, and it isn't medical advice. Always read the packaging and patch-test where indicated.
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