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
1 study endpoint found for Guanidine Hydrochloride. 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 | 100 mg/kg bw/day | oral | rat | oral | REACH |
GHS Hazard Classification
Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.
Expert Verdict
Generates highly alkaline calcium hydroxide/guanidine carbonate system in relaxers; causes chemical burns, alopecia, and severe eye damage if misused; strict pH control mandatory
Frequently Asked Questions
Is Guanidine Hydrochloride safe in cosmetics?
Generates highly alkaline calcium hydroxide/guanidine carbonate system in relaxers; causes chemical burns, alopecia, and severe eye damage if misused; strict pH control mandatory The EU classifies Guanidine Hydrochloride as "prohibited". Safety rating: MODERATE. 1 toxicological study endpoint(s) are available in our database.
Is Guanidine Hydrochloride allowed in the EU?
Guanidine Hydrochloride EU regulatory status: prohibited. Maximum allowed concentration: 7%. This is based on EU Regulation 1223/2009 and its amendments.
What does Guanidine Hydrochloride do in cosmetics?
Guanidine Hydrochloride functions as: Buffering. It is classified as a cosmetic ingredient in our database. CAS number: 50-01-1.
What is the Margin of Safety for Guanidine Hydrochloride?
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.
What is the NOAEL for Guanidine Hydrochloride?
The NOAEL (No Observed Adverse Effect Level) for Guanidine Hydrochloride is 100 mg/kg bw/day based on a oral study via oral route in rat. Source: REACH.
Compliance Tools
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Related Ingredients
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