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
5 study endpoints found for Cyclotetrasiloxane. 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 |
|---|---|---|---|---|---|
| LOAEL | 745 mg/kg bw/day | oral | mouse | Subchronic | COSMOS_DB |
| LOAEL | 335 mg/kg bw/day | oral | rat | Subchronic | COSMOS_DB |
| NOAEL | 100 mg/kg bw/day | oral | rat | Chronic | COSMOS_DB |
| LOAEL | 210 mg/kg bw/day | oral | rat | Chronic | COSMOS_DB |
| LOAEL | 60 mg/kg bw/day | oral | mouse | Chronic | COSMOS_DB |
GHS Hazard Classification
Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.
Expert Verdict
EU Regulation 2024/1328 restricts D4 at ≥0.1% w/w in all consumer and professional products effective June 6, 2026. ECHA SVHC since 2018 as PBT, vPvB, and potential endocrine disruptor. Classified as toxic to aquatic life and detected in remote polar environments and human tissue. Full reformulation away from D4 is required for EU-market products. Stockholm Convention POPs listing proposed.
Regulatory Flags
Frequently Asked Questions
Is Cyclotetrasiloxane safe in cosmetics?
EU Regulation 2024/1328 restricts D4 at ≥0.1% w/w in all consumer and professional products effective June 6, 2026. ECHA SVHC since 2018 as PBT, vPvB, and potential endocrine disruptor. Classified as toxic to aquatic life and detected in remote polar environments and human tissue. Full reformulation away from D4 is required for EU-market products. Stockholm Convention POPs listing proposed. The EU classifies Cyclotetrasiloxane as "restricted". Safety rating: POOR. 5 toxicological study endpoint(s) are available in our database.
Is Cyclotetrasiloxane allowed in the EU?
Cyclotetrasiloxane EU regulatory status: restricted. Maximum allowed concentration: ≥0.1% w/w prohibited in all consumer and professional products under EU Reg 2024/1328; enforcement June 6, 2026. This is based on EU Regulation 1223/2009 and its amendments.
What does Cyclotetrasiloxane do in cosmetics?
Cyclotetrasiloxane functions as: solvent, volatile carrier, conditioning agent. It is classified as a cosmetic ingredient in our database. CAS number: 556-67-2.
What is the Margin of Safety for Cyclotetrasiloxane?
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 Cyclotetrasiloxane?
The NOAEL (No Observed Adverse Effect Level) for Cyclotetrasiloxane is 745 mg/kg bw/day based on a Subchronic study via oral route in mouse. A total of 5 study endpoints are available. Source: COSMOS_DB.
Compliance Tools
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Related Ingredients
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