Reference summary — not medical advice or a personal risk estimate.

Shampoo

Liquid hair cleansers, including baby, dandruff, and colour-safe formulas.

Also known as: hair wash

IARC-classified factors documented in this product

IARC Group 1Coal-tar and coal-tar pitchhigh confidence
Contains · Source: US FDA
Ingredient in medicated anti-dandruff/psoriasis shampoos (Denorex, Neutrogena T/Gel).
IARC Group 1Formaldehydehigh confidence
Byproduct of ingredients · Source: EPA CPDat
Released by preservatives like DMDM Hydantoin, Quaternium-15, Imidazolidinyl Urea.
IARC Group 1Benzenemedium confidence
Contamination · Source: EPA CPDat
Trace contaminant found in some hair-care formulations.

How to read this page

A factor appearing on this page means it has been documented in this product category — through EPA / FDA testing, IARC monographs, or regulatory recall records. Whether it presents a meaningful personal risk depends on the specific formulation, dose, and how you're exposed. Click any factor to read what science actually says about it, and where.