Get a Free 5ml Mini Now Free 5ml Mini With Every Order of The Mantle
Moumoujus

1,2,4-TRIHYDROXYBENZENE.

Avoid CAS 533-73-3 / HAIR DYEING

1,2,4-Trihydroxybenzene is a chemical primarily employed in hair dye formulations as an auto-oxidative colorant. Research indicates that in human keratinocytes, it severely exacerbates oxidative stress, induces DNA damage, and leads to cell death by damaging critical organelles. Its use in skincare is strongly cautioned against due to its potent sensitizing and genotoxic properties.

Summary

Hair Colorant

Science

Mechanism of Action

1,2,4-Trihydroxybenzene acts by triggering severe cellular distress within human keratinocytes, initiating stress granule formation and activating the PERK-eIF2α signaling pathway. This compound significantly amplifies oxidative stress, generating reactive oxygen species such as superoxide and hydroxyl radicals, which in turn cause DNA double-strand breaks. Such damage ultimately destroys vital cellular components including mitochondria and the endoplasmic reticulum, culminating in cell death. Furthermore, it functions as an auto-oxidative dye, undergoing oxidation spontaneously at physiological pH or enzymatically to form coupled products and 2-hydroxy-1,4-benzoquinone. In vitro studies confirm its genotoxic potential through the induction of DNA damage.

Research

Clinical Evidence

Low confidence
Effective range N/A
Optimal

N/A

Transparency

Dusting Analysis

Not commonly dusted

The Formula

Formulation

Solubility
Water
Optimal pH N/A
0 7 14

Stability

This ingredient exhibits poor stability, being highly prone to oxidation, particularly at physiological or alkaline pH levels and when exposed to oxygen. The presence of iron and copper salts significantly accelerates its degradation. In typical hair dye formulations at pH 9, over 70% can react within 5 minutes when exposed to air. Stability can be maintained for several hours at room temperature if protected from light and kept under an inert gas.

Conflicts

  • Oxygen
  • Alkaline pH
  • Iron salts
  • Copper salts

Safety

Safety Profile

CIR Status
Safe with restrictions
Max tested
2.5%%
Sensitization risk High

The CIR Expert Panel found 1,2,4-Trihydroxybenzene safe for use in hair dye formulations up to 2.5%, designating it as a coal tar hair dye requiring specific FDA caution statements and patch test instructions. However, the SCCS initially deemed the data insufficient for assessing its safe use and characterized it as an extreme skin sensitizer. Subsequent submissions supported its application up to 2.5% in permanent hair dyes and 0.7% in gradual hair coloring shampoos, exclusively within the context of hair coloring.

Your Skin

Skin Compatibility

No Normal
No Dry
No Oily
No Sensitive
Irritancy High
Comedogenicity Unknown

Our Assessment

Verdict

Avoid

This ingredient is contraindicated for skincare due to its documented high irritancy, extreme sensitizing potential, and severe cellular toxicity, including DNA damage and induction of cell death in human keratinocytes.

Related

Similar Ingredients

Finding similar ingredients…