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
10 study endpoints found for Magnesium Hydroxide. 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 | Special Toxicology Study | COSMOS_DB |
| NOAEL | 50 mg/kg bw/day | oral | rat | Chronic | COSMOS_DB |
| NOAEL | 100 mg/kg bw/day | oral | rat | Special Toxicology Study | COSMOS_DB |
| dose_tested | 100 mg/kg bw/day | oral | rat | Special Toxicology Study | COSMOS_DB |
| dose_tested | 50 mg/kg bw/day | oral | rat | Chronic | COSMOS_DB |
| dose_tested | 100 mg/kg bw/day | oral | rat | Special Toxicology Study | COSMOS_DB |
| NOAEL | >=1000 mg/kg bw/day | oral | rat | oral | REACH |
| NOAEL | 308 mg/kg bw/day | oral | rat | oral | REACH |
| NOAEL | 308 mg/kg bw/day | oral | - | oral | REACH |
| NOAEL | 6810 mg/kg bw/day | oral | mouse | oral | REACH |
Expert Verdict
Generally well-tolerated; alkaline nature (pH ~10 in solution) can cause irritation at very high concentrations or on damaged skin; standard good-formulation practice limits pH of finished product. Occurs naturally as mineral brucite; typical use 0.2-1.5% as pH adjuster, up to 30% as absorbent/filler; effective oil-absorbing properties that bind sebum from pores
Regulatory Flags
Frequently Asked Questions
Is Magnesium Hydroxide safe in cosmetics?
Generally well-tolerated; alkaline nature (pH ~10 in solution) can cause irritation at very high concentrations or on damaged skin; standard good-formulation practice limits pH of finished product. Occurs naturally as mineral brucite; typical use 0.2-1.5% as pH adjuster, up to 30% as absorbent/filler; effective oil-absorbing properties that bind sebum from pores The EU classifies Magnesium Hydroxide as "restricted". Safety rating: MODERATE. 10 toxicological study endpoint(s) are available in our database.
Is Magnesium Hydroxide allowed in the EU?
Magnesium Hydroxide EU regulatory status: restricted. This is based on EU Regulation 1223/2009 and its amendments.
What does Magnesium Hydroxide do in cosmetics?
Magnesium Hydroxide functions as: Absorbent, pH buffering/neutralizing agent, filler, texturizer. It is classified as a cosmetic ingredient in our database. CAS number: 1309-42-8.
What is the Margin of Safety for Magnesium Hydroxide?
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 Magnesium Hydroxide?
The NOAEL (No Observed Adverse Effect Level) for Magnesium Hydroxide is 100 mg/kg bw/day based on a Special Toxicology Study study via oral route in rat. A total of 10 study endpoints are available. Source: COSMOS_DB.
Compliance Tools
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