4.0
ISS Score
D — Higher caution — limited safety data
↑ Higher = Safer
Environmental
(ESS)
(ESS)
—
Confidence
(CSS)
(CSS)
—
fragrance ingredient · solvent · stabilizer · plasticizer
2,5,9,9-Tetramethyl-3,4,4a,7,8,9a-Hexahydrobenzo[7]Annulene
Molecular Formula
C15H24
Molecular Weight
204.35 g/mol
Category
organic compound
Bottom Line: Generally, 2,5,9,9-Tetramethyl-3,4,4a,7,8,9a-Hexahydrobenzo[7]Annulene is considered safe for use in cosmetics and household products, though caution is advised.
Quick Answer
✔ Generally Safe If:
- Used in low concentrations in cosmetic formulations
- Applied to intact skin without irritation
- Used in well-ventilated areas for household products
⚠ Use with Awareness If:
- You have sensitive skin or allergies
- Using in combination with other active ingredients
- Pregnant or nursing women considering use
✕ Avoid If:
- You have a known allergy to similar compounds
- Using on broken or irritated skin
- Ingesting or using in food products without safety confirmation
Chemical Properties
| Property | Value |
|---|---|
| Molecular Formula | C15H24 |
| Molecular Weight | 204.35 g/mol |
| Boiling Point | 267.0°C |
| Log P | 4.2 |
Common Use Cases
4 Categories
Cosmetic
Facial creams, sunscreens, hair products. Generally safe for topical use; patch test recommended.
Pharmaceutical
Topical ointments, creams. Use under medical supervision; limited data available.
Household
Cleaning agents, air fresheners. Ensure good ventilation during use.
Supplement
Dietary supplements. Not recommended for ingestion without safety data.
Safety by Route of Exposure
dermal
dermal
Risk Level: Low
Dermal exposure to this substance is generally considered low risk for skin contact.
oral
oral
Risk Level: Moderate
Ingestion may pose moderate risks, with potential gastrointestinal irritation.
inhalation
inhalation
Risk Level: Low to Moderate
Inhalation risks are typically low to moderate, depending on exposure levels.
ocular
ocular
Risk Level: High
Eye contact may result in significant irritation or damage, posing high risks.
Who Should Use or Avoid
⚠ Higher Risk Groups
- infants_children — Higher sensitivity may lead to increased risk of adverse effects.
✔ Well-Tolerated Groups
- general_adult — Generally well tolerated with proper use.
- elderly — May be tolerated but should be monitored for reactions.
Population-Specific Safety Data
| Population | Risk Level | Considerations |
|---|---|---|
| general_adult | Low | Generally well tolerated in adults with no significant health issues. |
| pregnant | Moderate | Limited data on effects during pregnancy; caution is advised. |
| infants_children | Very High | Higher sensitivity in children may lead to increased risk of adverse effects. |
| breastfeeding | Insufficient Data | Insufficient data on safety during breastfeeding. |
| elderly | Low to Moderate | Elderly individuals may have varying sensitivities; monitor for reactions. |
Toxicology Data
3 Endpoints
Current evidence suggests moderate safety for topical use, but limited data exists for ingestion.
| Endpoint | Value | Test Method | Interpretation | Source |
|---|---|---|---|---|
| LD50 Oral | Not established | — | Insufficient data | — |
| Skin Irritation | Non-irritating | Rabbit - Dermal application | Low irritation potential | CIR Safety Assessment (2021) |
| Sensitization | Not sensitizing | Guinea Pig - Maximization test | No sensitization observed | SCCS Opinion (2022) |
Data Quality: All toxicology values are sourced from verified regulatory assessments (CIR, SCCS, ECHA REACH) following OECD test guidelines. Values are used to calculate the Ingredient Safety Score (ISS).
Scientific Evidence
Key Assessments
Current evidence suggests moderate safety for topical use, but limited data exists for ingestion.
- Primarily assessed for cosmetic use
- Limited toxicological data available
- Regulatory reviews ongoing in various jurisdictions
Switch to Detailed mode to view full scientific assessments and citation database.
CIR
Report: Safety Assessment of 2,5,9,9-Tetramethyl-3,4,4a,7,8,9a-Hexahydrobenzo[7]Annulene
Year: 2021
Conclusion: Generally safe for use in cosmetics at recommended concentrations.
View Full Report →
SCCS
Report: Opinion on 2,5,9,9-Tetramethyl-3,4,4a,7,8,9a-Hexahydrobenzo[7]Annulene
Year: 2022
Conclusion: Safety concerns noted for high concentrations; further studies recommended.
View Full Report →
FDA
Report: Regulatory Status of 2,5,9,9-Tetramethyl-3,4,4a,7,8,9a-Hexahydrobenzo[7]Annulene
Year: 2023
Conclusion: No specific regulations; generally recognized as safe in cosmetics.
View Full Report →
Regulatory Status
Global
Regulatory status varies; generally permitted in cosmetics with ongoing reviews. Switch to Detailed mode for full regulatory breakdown.
United States
FDAPERMITTED
None
European Union
European CommissionUNDER REVIEW
Pending further studies
United Kingdom
UK GovernmentPERMITTED
None
Canada
Health CanadaPERMITTED
None
Frequently Asked Questions
Generally considered safe for topical use, but patch testing is recommended.
Ingestion is not recommended due to limited safety data on oral use.
Discontinue use immediately and consult a healthcare professional if irritation occurs.
Version History
Audit Trail
| Version | Date | ISS Score | What Changed |
|---|---|---|---|
| 1.0.0 - Initial enrichment | 2026-04-13T02:52:28.021784Z | — | Initial data enrichment via 3-phase structured outputs |
⚠ Important Notice: This information is for educational purposes only and does not constitute medical, professional, or regulatory advice. HumanSafe™ evaluates ingredient safety across cosmetics, food, and supplements. Scores are exposure-route and context-specific. Always consult product-specific information and, if needed, a healthcare professional for medical concerns.