Sodium Lauryl Sulfate (SLS)

CAS 151-21-3 · C₁₂H₂₅NaO₄S · sls · sodium lauryl sulfate · sodium dodecyl sulfate

A strong detergent surfactant that strips the skin barrier and may irritate sensitive skin. Common in foaming products.

high confidence

Researched April 18, 2026

Annotation registerSpecimen 0004

NameSodium Lauryl Sulfate (SLS)

CAS: 151-21-3
Formula: C₁₂H₂₅NaO₄S
Verdict: Caution

Concerns

Disrupts skin barrier — increases transepidermal water loss
Oral irritation and canker sore association
Eye irritant
May worsen eczema-prone skin

Commonly found in

ShampooBody washToothpasteFace washDish soap

Research disclaimer: This rating is based on available peer-reviewed research and regulatory assessments at the time of publication. It is not medical advice. Consult a qualified professional for personal health or skin concerns.

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