Ammonium Lauryl Sulfate
The question

Is Ammonium Lauryl Sulfate safe in shampoo?

CautionShampoo

An anionic lauryl-sulfate cleansing surfactant whose main issue is concentration- and contact-time-dependent skin irritation, generally considered acceptable in rinse-off products.

What the research flags

  • Anionic lauryl-sulfate surfactants reduce the surface tension of the stratum corneum and can damage the skin barrier, carrying an irritant and, less commonly, an allergic contact-dermatitis potential (Salomon 2022, PMID 36856374)
  • Lauryl-sulfate surfactant challenge denatures stratum-corneum proteins and increases transepidermal water loss, with the effect proportional to concentration and to the number of repeated exposures (Goffin 1999, PMID 10457137; data on the sodium analog)
  • Per the Cosmetic Ingredient Review safety assessment, ammonium/sodium lauryl sulfate is considered safe primarily for brief, rinse-off use, with prolonged (leave-on) skin contact limited to about 1 percent because irritation rises with concentration and contact time (CIR final report)

Regulatory
IARC Class: NL

Other shampoo ingredients on file

Sources & references

  1. [1]
    Peer-reviewedPubMed / NCBI — pubmed.ncbi.nlm.nih.gov · ref 36856374
  2. [2]
    Peer-reviewedPubMed / NCBI — pubmed.ncbi.nlm.nih.gov · ref 10457137
  3. [3]
    Newsjournals.sagepub.com — journals.sagepub.com · ref 10915818309142005

Research disclaimer: Ratings reflect peer-reviewed research and regulatory assessments available at the time of publication, not the dose or formulation of any specific shampoo product. This is not medical advice.