Regulatory Status
For full compliance data across 55 jurisdictions, use the Substance Compliance tool.
Safety Data
Calculate MoS for your specific formulation with the MoS Calculator.
Toxicological Studies
2 study endpoints found for L-Lysine. NOAEL (No Observed Adverse Effect Level) values are used to calculate the Margin of Safety per SCCS methodology.
| Endpoint | Value | Route | Species | Study Type | Source |
|---|---|---|---|---|---|
| NOAEL | 2100 mg/kg bw/day | oral | rat | Short Term Toxicity | COSMOS_DB |
| dose_tested | 2100 mg/kg bw/day | oral | rat | Short Term Toxicity | COSMOS_DB |
Expert Verdict
L-Lysine's positive charge at physiological pH is functionally critical for peptide formulation, improving membrane binding and percutaneous penetration. As the K in the KTTKS Matrixyl sequence, it has GRAS status and CIR approval confirming excellent safety with no restrictions.
Regulatory Flags
Frequently Asked Questions
Is L-Lysine safe in cosmetics?
L-Lysine's positive charge at physiological pH is functionally critical for peptide formulation, improving membrane binding and percutaneous penetration. As the K in the KTTKS Matrixyl sequence, it has GRAS status and CIR approval confirming excellent safety with no restrictions. The EU classifies L-Lysine as "permitted". Safety rating: EXCELLENT. 2 toxicological study endpoint(s) are available in our database.
Is L-Lysine allowed in the EU?
L-Lysine EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does L-Lysine do in cosmetics?
L-Lysine functions as: Essential amino acid with a positively charged side chain (pKa ~10.5) at physiological pH. In cosmetic context: facilitates peptide-membrane adhesion by binding to the negatively charged lipid bilayer; enhances peptide penetration when positioned at sequence extremities; structural component of collagen-stimulating sequences (KTTKS in Palmitoyl Pentapeptide-4/Matrixyl). Serves as counter-ion for pH adjustment and as a skin conditioning humectant.. It is classified as a Active Ingredient in our database. CAS number: 56-87-1.
What is the Margin of Safety for L-Lysine?
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.
What is the NOAEL for L-Lysine?
The NOAEL (No Observed Adverse Effect Level) for L-Lysine is 2100 mg/kg bw/day based on a Short Term Toxicity study via oral route in rat. A total of 2 study endpoints are available. Source: COSMOS_DB.
Compliance Tools
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Related Ingredients
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