Regulatory Status
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Safety Data
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Expert Verdict
No CIR review found; relies on supplier MSDS and general quat safety data; dimethyl sulfate used in synthesis — must confirm residual levels are controlled
Frequently Asked Questions
Is Quaternium-91 safe in cosmetics?
No CIR review found; relies on supplier MSDS and general quat safety data; dimethyl sulfate used in synthesis — must confirm residual levels are controlled The EU classifies Quaternium-91 as "permitted". Safety rating: GOOD.
Is Quaternium-91 allowed in the EU?
Quaternium-91 EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does Quaternium-91 do in cosmetics?
Quaternium-91 functions as: Hair conditioning agent. It is classified as a cosmetic ingredient in our database. CAS number: No publicly assigned CAS found; COSING Ref No. 58942.
What is the Margin of Safety for Quaternium-91?
not established The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.
Compliance Tools
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Related Ingredients
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