murphyNonoxynol-4
AKA: Ammonium 2-(4-nonylphenoxy)ethyl sulfate, 31691-97-1, Azanium;2-(4-nonylphenoxy)ethyl sulfate
Synthetic
Cleanser
Not Clean
OriginDerived from nonylphenol, a synthetic organic compound produced from petrochemical sources. Synthesized through ethoxylation of nonylphenol with ethylene oxide to create the nonionic surfactant.
Ammonium Nonoxynol-4 Sulfate is the ammonium salt of sulfated Nonoxynol-4
Formula
C17H31NO5S
Mol. Weight
361.50
CAS #
31691-97-1
Form
Liquid
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Caution
Functions
Cleansing
Makes oil and water mix so dirt, makeup, and sunscreen can actually be washed away. The reason your face wash foams.
Removes Impurities
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory0 listings
🛡️Safety-assessed3 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
EWG
4
CIR
Safe as used
Pregnancy
Caution
CIR Safety Findings
Eye Irritant in Testing
2 studies / 2 irritating / reactions minimal to severe (CIR 695)
Mixed Skin Irritation Results
4 studies / 2 irritating / 1 mixed / 1 not irritating / reactions slight to moderate (CIR 44 and 212 and 695)
Mixed Sensitization Results
2 studies / 1 sensitizing / 1 not sensitizing (CIR 44 and 212)
Dermal Absorption 0.66–1%
3 results from in vitro tests in the CIR safety assessment (CIR 44 and 695)
Concentration Guide
CIR's newest survey reports no concentration of use.
CIR · 2014 survey
Regulatory Agencies
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR