Is Polyquaternium-51 safe in cosmetics?
Polyquaternium-51 has a safety rating of "EXCELLENT" in our database. EU status: permitted. US status: permitted. This ingredient has been reviewed by cir.
Polyquaternium-51
Also known as: 2-[(2-Methylprop-2-enoyl)oxy]ethyl 2-(trimethylazaniumyl)ethyl phosphate--butyl 2-methylprop-2-enoate (1/1), 3,5,8-Trioxa-4-phosphaundec-10-en-1-aminium, 4-hydroxy-N,N,N,10- tetramethyl-9-oxo-, inner salt, 4-oxide, polymer with butyl 2-methyl-2- propenoate, 2-Propenoic acid, 2-methyl-, butyl ester, polymer with 4-hydroxy- N,N,N,10-tetramethyl-9-oxo-3,5,8-trioxa-4-phosphaundec-10-en-1-aminium inner salt 4-oxide, 2-Methacryloyloxyethylphosphorylcholine-butyl methacrylate copolymer, Butyl methacrylate-2-(methacryloyloxy)ethyl-2'- (trimethylammonio)ethyl phosphate copolymer (+4 more)
INCI: POLYQUATERNIUM-51
Polyquaternium-51 (CAS 125275-25-4) is a cosmetic cosmetic ingredient functioning as Film Forming, Skin Conditioning, Humectant. EU Regulation 1223/2009 status: permitted; 1 safety opinion reviewed (cir). Industrial safety data is also available in the chemical safety database.
View industrial chemical safety profile for CAS 125275-25-4 →
Auto-generated CPSR Part A draft with source citations
Function
Film Forming, Skin Conditioning, Humectant
Safety Rating
EXCELLENT
Regulatory Status
EU EU Status
permitted
US US Status
permitted
US Notes
CIR Expert Panel concluded safe in cosmetics in present practices of use and concentration (2022). 275 products in VCRP.
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Polyquaternium-51.
Calculate MoS for your specific formulation with the MoS Calculator.
Safety Opinions
Official safety assessments from the Scientific Committee on Consumer Safety (SCCS) and Cosmetic Ingredient Review (CIR).
cir
July 11, 2022
Verdict: safe
ine polymers, as used in cosmetic formulations. The Panel concluded that these ingredients are safe in cosmetics in the present practices of use and concentration described in this safety assessment. The Panel considered the available data included in this assessment to be adequate for determinin
Typical Use Concentrations
Reported concentration ranges per product category from SCCS/CIR/industry sources.
| Product Category | Typical Range | Max Reported | Source |
|---|---|---|---|
| Face Cream | 0.05–0.14 | 0.14 | CIR (PCPC survey 2020) |
Additional Ingredient Properties
2 property records from structured ingredient metadata.
hair_care
{"hair_function": "moisturizing", "hair_type_suitability": "all", "curl_pattern_suitability": "all", "porosity_suitability": "all", "protein_sensitivity": "moisture", "moisture_protein_balance": "yes", "cg_method_approved": "not-a-silicone", "silicone_type": "not-a-sulfate", "sulfate_type": "no", "drying_alcohol": "no", "fatty_alcohol": "no", "heat_protectant": "yes", "color_safe": "neutral", "ker…
humectant
{"cas_number": "179211-04-0", "ingredient_class": "humectant/film_former_moisturizing", "molecular_weight_Da": "variable", "chemical_type": "synthetic_polymer", "water_binding_mechanism": "hydrogen_bonding/film_forming", "water_holding_capacity_g_per_g": "0.5-1.0", "hygroscopicity_at_50_RH": "excellent", "hygroscopicity_at_80_RH": "excellent", "NMF_component": "no", "NMF_percentage_natural": "0", …
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Film former
Humectant
Softener and conditioner
Expert Verdict
Expert safety assessment and concern-level summary for Polyquaternium-51.
Known Synonyms
2-[(2-Methylprop-2-enoyl)oxy]ethyl 2-(trimethylazaniumyl)ethyl phosphate--butyl 2-methylprop-2-enoate (1/1)
3,5,8-Trioxa-4-phosphaundec-10-en-1-aminium, 4-hydroxy-N,N,N,10- tetramethyl-9-oxo-, inner salt, 4-oxide, polymer with butyl 2-methyl-2- propenoate
2-Propenoic acid, 2-methyl-, butyl ester, polymer with 4-hydroxy- N,N,N,10-tetramethyl-9-oxo-3,5,8-trioxa-4-phosphaundec-10-en-1-aminium inner salt 4-oxide
2-Methacryloyloxyethylphosphorylcholine-butyl methacrylate copolymer
Butyl methacrylate-2-(methacryloyloxy)ethyl-2'- (trimethylammonio)ethyl phosphate copolymer
Butyl methacrylate-2- methacryloyloxyethylphosphorylcholine copolymer
Lipidure PMB
n-Butyl methacrylate-2-methacryloyloxyethylphosphorylcholine
2-(N,N,N-trimethylamino)ethyl 2-(2-methyl-2-propenoyloxy)ethyl phosphate inner salt, polymer with butyl 2-methyl-2-propenoate
Chemical Function
Film former
Softener and conditioner
Humectant
Australian Status
AICIS status: listed_with_terms
Assessment: This chemical has been assessed as a component of dermal cosmetic products at concentrations no more than 5%. This chemical is not to be used in topical products intended for the eye.
Frequently Asked Questions
Is Polyquaternium-51 allowed in the EU?
Polyquaternium-51 EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does Polyquaternium-51 do in cosmetics?
Polyquaternium-51 functions as: Film Forming, Skin Conditioning, Humectant. It is classified as a cosmetic ingredient in our database. CAS number: 125275-25-4.
Compliance Tools
Check Polyquaternium-51 compliance across multiple jurisdictions:
Ingredient Decoder
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82 Allergen Checker
Check for EU declarable fragrance allergens
Substance Compliance
Check compliance across multiple jurisdictions
MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
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