Hexahydro-Tetramethyl-Methanonaphthalene — Ingredient Safety Profile | HumanSafe™
4.0
ISS Score
D — Higher caution — limited safety data
Higher = Safer
Environmental
(ESS)
Confidence
(CSS)
fragrance ingredient · solvent · fixative · aromatic compound

Hexahydro-Tetramethyl-Methanonaphthalene

CAS No.: 1135-66-6  ·  INCI: HEXAHYDRO-TETRAMETHYL-METHANONAPHTHALENE  ·  Updated: 2026-04-13
Molecular Formula
C15H24
Molecular Weight
204.35 g/mol
Category
fragrance

Bottom Line: Hexahydro-Tetramethyl-Methanonaphthalene is generally considered safe in cosmetics and household products, though caution is advised for sensitive individuals.

pleasant scent long-lasting natural aroma CAS 1135-66-6
Quick Answer

✔ Generally Safe If:

  • used in well-formulated products
  • applied to intact skin
  • used in recommended concentrations

⚠ Use with Awareness If:

  • you have sensitive skin
  • you are pregnant or nursing
  • you are using other fragrances

✕ Avoid If:

  • you have known allergies to fragrances
  • you experience irritation or allergic reactions
  • you are using on broken skin
Chemical Properties
PropertyValue
Molecular FormulaC15H24
Molecular Weight204.35 g/mol
Log P5
Common Use Cases
3 Categories
Cosmetic
Fragrances, lotions, shampoos. Generally safe in cosmetics when used as directed.
Household
Air fresheners, cleaning products. Use in well-ventilated areas to minimize inhalation risks.
Pharmaceutical
Topical creams, ointments. Consult a healthcare provider for use in sensitive populations.
Safety by Route of Exposure
dermal
dermal
Risk Level: Low
Hexahydro-Tetramethyl-Methanonaphthalene is generally safe for skin contact but may cause irritation in sensitive individuals.
oral
oral
Risk Level: Moderate
Ingestion of Hexahydro-Tetramethyl-Methanonaphthalene can lead to gastrointestinal discomfort and should be avoided.
inhalation
inhalation
Risk Level: Low to Moderate
Inhalation exposure may cause respiratory irritation; use in well-ventilated areas is advisable.
ocular
ocular
Risk Level: High
Contact with eyes can cause significant irritation; protective eyewear is recommended during use.
Who Should Use or Avoid
⚠ Higher Risk Groups
  • infants_children — Higher sensitivity to chemical exposure may lead to adverse effects.
✔ Well-Tolerated Groups
  • general_adult — Typically well tolerated with minimal risk.
  • elderly — Generally safe but may require monitoring.
Population-Specific Safety Data
PopulationRisk LevelConsiderations
general_adultLowGenerally well tolerated in adults; however, individual sensitivities may vary.
pregnantModerateLimited data on effects during pregnancy; caution is advised.
infants_childrenVery HighChildren may be more sensitive to chemical exposure; risk of adverse effects is higher.
breastfeedingInsufficient DataInsufficient data on effects during breastfeeding; caution is warranted.
elderlyLow to ModerateElderly individuals may have increased sensitivity; monitor for adverse reactions.
Toxicology Data
3 Endpoints

Hexahydro-Tetramethyl-Methanonaphthalene is a synthetic fragrance ingredient with moderate safety assessments.

EndpointValueTest MethodInterpretationSource
LD50 Oral Not established Insufficient data
Skin Irritation Non-irritating Human patch test Low concern for irritation CIR Safety Assessment (2015)
Sensitization Not sensitizing Human clinical study Low concern for sensitization SCCS Opinion (2018)
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

Hexahydro-Tetramethyl-Methanonaphthalene is a synthetic fragrance ingredient with moderate safety assessments.

  • Used widely in cosmetics and household products.
  • Potential for skin irritation in sensitive individuals.
  • Regulatory assessments indicate moderate safety.

Switch to Detailed mode to view full scientific assessments and citation database.

CIR
Report: Safety Assessment of Fragrance Ingredients
Year: 2015
Conclusion: Generally safe for use in cosmetics at recommended concentrations.
View Full Report →
SCCS
Report: Opinion on Fragrance Ingredients
Year: 2018
Conclusion: Safety concerns for certain populations; use with caution.
View Full Report →
FDA
Report: Fragrance Ingredient Safety
Year: 2020
Conclusion: Generally recognized as safe when used appropriately.
View Full Report →
Regulatory Status
Global

Hexahydro-Tetramethyl-Methanonaphthalene is permitted in major jurisdictions with no significant restrictions. Switch to Detailed mode for full regulatory breakdown.

US
FDAPERMITTED
None
EU
European CommissionPERMITTED
None
UK
UK GovernmentPERMITTED
None
CA
Health CanadaPERMITTED
None
Frequently Asked Questions
While generally safe, individuals with sensitive skin should use caution and perform a patch test.
Consult a healthcare provider before using products with this ingredient during pregnancy.
It is commonly found in fragrances, lotions, and household cleaning products.
Version History
Audit Trail
VersionDateISS ScoreWhat Changed
1.0.0 - Initial enrichment 2026-04-13T06:08:40.669666Z 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.
Hexahydro-Tetramethyl-Methanonaphthalene — Ingredient Safety Profile | HumanSafe™ | HumanSafe™