Cysteic Acid
Regulatory Status
For full compliance data across 55 jurisdictions, use the Substance Compliance tool.
Safety Data
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Expert Verdict
Cysteic acid is a permitted amino acid-derived conditioning agent with adequate safety margin; monitor for low-level irritation in leave-on formulations at high concentrations due to acidity.
Frequently Asked Questions
Is Cysteic Acid safe in cosmetics?
Cysteic acid is a permitted amino acid-derived conditioning agent with adequate safety margin; monitor for low-level irritation in leave-on formulations at high concentrations due to acidity. The EU classifies Cysteic Acid as "permitted". Safety rating: GOOD.
Is Cysteic Acid allowed in the EU?
Cysteic Acid EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What is the Margin of Safety for Cysteic Acid?
adequate 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
Check Cysteic Acid compliance across multiple jurisdictions:
Related Ingredients
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