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HOW WE DETERMINE SCORES Learn more About EWG VERIFIED®

Data: Fair

Steartrimonium Chloride

IMAGE SOURCE: PubChem

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Other Concerns

Use restrictions (high), Neurotoxicity (low), Endocrine disruption (low), and Non-reproductive organ system toxicity (low_moderate)

SYNONYMS

● EINECS 203-929-1
● DSSTOX_CID_6902
● EC 203-929-1
● MONOSTEARYL TRIMETHYL AMMONIUM CHLORIDE
● N-OCTADECYLTRIMETHYLAMMONIUM CHLORIDE
● ARQUAD 18-50
● C21H46CLN
● AMMONIUM, TRIMETHYLOCTADECYL-, CHLORIDE
● TRIMETHYLOCTADECYLAMMONIUM CHLORIDE, >=95.0% (CALC. ON DRY SUBSTANCE, T)
● STEARTRIMONIUM CHLORIDE

Unacceptable

Unacceptable: EWG VERIFIED products cannot contain this ingredient

Steartrimonium Chloride is a quaternary ammonium salt.

Common concerns

See how this product scores for common concerns.

  • LOW
    Cancer
  • HIGH
    Allergies & Immunotoxicity
  • LOW
    Developmental and Reproductive Toxicity
  • HIGH
    Use Restrictions

Ingredient concerns

  • CONCERNS
  • DATA SOURCES

Products with this Ingredient

Expand content Collapse content
conditioner62 products
hair styling aid15 products
hair treatment/serum25 products
mask15 products
bath oil/salts/soak3 products
hair color and bleaching29 products
detangler3 products
styling gel/lotion4 products
Hair Styling Gel1 products
shampoo4 products
hair-loss treatment1 products

Allergies/immunotoxicity

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CONCERN REFERENCE
Human toxicant or allergen - strong evidenceAsthmagen compilation - AEOC exposures codes(2012-01-01)
Human skin toxicant or allergen - strong evidenceCosmetic Ingredient Review (CIR)
Possible human respiratory toxicant or allergenEnvironmental Working Group 2020. Quaternary ammonium compounds structural similarities.(2020-12-01)
Known human [[system]] toxicant or allergenPeer Reviewed Literature
Limited evidence of respiratory toxicity or allergiesEnvironmental Working Group 2020. Quaternary ammonium compounds structural similarities.(2020-12-01)

Data gaps

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CONCERN REFERENCE
Risk assessment method deficiencies and data gaps - Maximum reported 'as used' concentration is basis of safety assessment by industry safety panel (Cosmetic Ingredient Review, CIR) - implicit safe concentration limit in productCosmetic Ingredient Review (CIR)

Use restrictions

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CONCERN REFERENCE
Determined safe for use in cosmetics, subject to concentration or use limitations - Safe for use in cosmetics with some qualificationsCosmetic Ingredient Review (CIR)
Determined safe for use in cosmetics, subject to concentration or use limitations - Distinction between safe conc in leave-on and rinse-offCosmetic Ingredient Review (CIR)
Violation of government restrictions - Restricted in cosmetics; use, concentration, or manufacturing restrictions - anyEU Cosmetics Directive

Organ system toxicity (non-reproductive)

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CONCERN REFERENCE
Classified as not expected to be potentially toxic or harmfulEnvironment Canada
Possible human toxicantAltered toxicological endpoints in humans from common quaternary ammonium compound disinfectant exposure(2021-01-01)

Persistence and bioaccumulation

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CONCERN REFERENCE
Not suspected to be persistentEnvironment Canada
Not suspected to be bioaccumulativeEnvironment Canada

Ecotoxicology

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CONCERN REFERENCE
Suspected to be an environmental toxinEnvironment Canada

Developmental/reproductive toxicity

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CONCERN REFERENCE
One or more animal studies show reproductive effects at moderate dosesQuaternary Ammonium Disinfectants Cause Subfertility in Mice by Targeting both Male and Female Reproductive Processes(2015-11-03)
One or more animal studies show reproductive effects at moderate dosesExposure to common quaternary ammonium disinfectants decreases fertility in mice(2014-12-01)

Endocrine disruption

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CONCERN REFERENCE
Associated with endocrine disruptionIdentification of Environmental Quaternary Ammonium Compounds as Direct Inhibitors of Cholesterol Biosynthesis(2016-06-01)

Neurotoxicity

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CONCERN REFERENCE
One or more in vitro tests on mammalian cells demonstrate neurotoxicityBenzalkonium Chloride Disinfectants Induce Apoptosis, Inhibit Proliferation, and Activate the Integrated Stress Response in a 3-D in Vitro Model of Neurodevelopment(2021-05-01)
  • Asthmagen compilation - AEOC exposures codes(2012-01-01)
  • Cosmetic Ingredient Review (CIR)
  • Environmental Working Group 2020. Quaternary ammonium compounds structural similarities.(2020-12-01)
  • Peer Reviewed Literature
  • EU Cosmetics Directive
  • Environment Canada
  • Altered toxicological endpoints in humans from common quaternary ammonium compound disinfectant exposure(2021-01-01)
  • Quaternary Ammonium Disinfectants Cause Subfertility in Mice by Targeting both Male and Female Reproductive Processes(2015-11-03)
  • Exposure to common quaternary ammonium disinfectants decreases fertility in mice(2014-12-01)
  • Identification of Environmental Quaternary Ammonium Compounds as Direct Inhibitors of Cholesterol Biosynthesis(2016-06-01)
  • Benzalkonium Chloride Disinfectants Induce Apoptosis, Inhibit Proliferation, and Activate the Integrated Stress Response in a 3-D in Vitro Model of Neurodevelopment(2021-05-01)

Understanding scores

Cosmetics and personal care products are not required to be tested for safety before being allowed on the market. The Skin Deep® scoring system was designed to help the public understand whether a product is safe to use or whether it contains ingredients of concern.

Every product and ingredient in Skin Deep gets a two-part score – one for hazard and one for data availability. The safest products score well by both measures, with a low hazard rating and a fair or better data availability rating.


HOW WE DETERMINE SCORES

Hazard score

The Skin Deep ingredient hazard score, from 1 to 10, reflects known and suspected hazards linked to the ingredients. The EWG Verified® mark means a product meets EWG’s strictest criteria for transparency and health.

Score legend
WEIGHT-OF-EVIDENCE APPROACH

A product’s hazard score is not an average of the ingredients’ hazard scores. It is calculated using a weight-of-evidence approach that factors in all of the hazards or health impacts associated with the ingredients.

Data availability

The Skin Deep data availability rating reflects the number of scientific studies about the product or ingredient in the published scientific literature.

NONE LIMITED FAIR GOOD ROBUST
Low Availability
Moderate Availability
High Availability
NONE

Ingredients have not been assessed.

LIMITED-FAIR

There is only a modest volume of research.

GOOD-ROBUST

Ingredients have been studied extensively.

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