Hydroquinone
Notable concerns
INCI · HydroquinoneCAS 123-31-9
Also known as: 1,4-Benzenediol
ConditioningAntioxidant
In plain language
The gold-standard active ingredient for skin bleaching; it aggressively inhibits melanin production to fade severe hyperpigmentation.
Can cause a permanent blue/black skin discoloration condition called exogenous ochronosis if used continuously without medical supervision.
Where it can be sold
Simplified regulatory status by market — for guidance, not compliance advice.
European UnionRestricted
Banned in skin-lightening cosmetics. Allowed only in artificial nail systems up to 0.02%.