Crystal Menthol, Menthol, L-Menthol, Levomenthol, Neomenthol, Peppermint Alcohol, Hexahydrothymol, 2216-51-5

Crystal Menthol, Menthol, L-Menthol, Levomenthol, Neomenthol, Peppermint Alcohol, Hexahydrothymol, 2216-51-5

CRYSTAL MENTHOL (L-MENTHOL)
PRODUCT IDENTIFICATION INFORMATION

CHEMICAL STRUCTURE

L-Menthol

OH
|
H₃C—CH—CH₂
|
| CH₂
H₃C—CH—CH₂
|
CH₃

Molecular Formula: C₁₀H₂₀O
SMILES: CC1CCC(C(C1)C(C)C)O
InChI: InChI=1S/C10H20O/c1-7(2)9-5-4-8(3)6-10(9)11/h7-11H,4-6H2,1-3H3/t8-,9+,10-/m1/s1
InChIKey: NOOLISFMXDJSKH-XKYBEWQOSA-N
Structure: Cyclic monoterpene alcohol; Contains a cyclohexane ring with three substituents; Has three chiral centers; Natural L-menthol is the most abundant and active isomer.

SECTION 1: CHEMICAL IDENTITY AND DESCRIPTION

SECTION 2: PHYSICAL AND CHEMICAL PROPERTIES

SECTION 3: MENTHOL ISOMERS

L-Menthol vs D-Menthol:

SECTION 4: CHEMICAL PROPERTIES AND REACTIVITY

SECTION 5: PRODUCTION METHODS

Method 1: Natural Extraction (Peppermint Oil)

Process: Peppermint plant → Harvest → Distillation → Peppermint Oil → Fractionation → Crystallization → L-Menthol

Description: Peppermint leaves are harvested and separated; Leaves are steam distilled; Menthol-containing oil is collected; Oil is fractionally distilled to concentrate menthol; Concentrated oil is cooled to crystallize L-menthol; Crystals are purified by recrystallization; This process is natural and does not require chemical synthesis.

Method 2: Synthetic Production (Thymol Route)

Process: Thymol → Hydrogenation → Isomenthol → Isomerization → L-Menthol

Description: Thymol (from thyme oil or synthetic) is hydrogenated to isomenthol; Isomenthol is isomerized to L-menthol; Racemic menthol is obtained; Resolution is used to obtain pure L-menthol. Less common.

Method 3: Synthetic Production (Citronellal Route)

Process: Citronellal → Cyclization → Isopulegol → Hydrogenation → L-Menthol

Description: Citronellal (from citronella oil or synthetic) is cyclized to isopulegol; Isopulegol is hydrogenated to L-menthol; High enantiomeric purity can be achieved. Increasingly common.

Method 4: Crystallization from Peppermint Oil

Process: Peppermint oil → Cooling (−40°C) → Filtration → Washing → Drying → L-Menthol crystals

Description: Peppermint oil is cooled to very low temperatures; L-menthol crystallizes out; Crystals are filtered, washed, and dried; Gives high purity natural L-menthol.

SECTION 6: FUNCTIONAL PROPERTIES AND MECHANISM OF ACTION

SECTION 7: MAIN APPLICATION AREAS

SECTION 8: SAMPLE FORMULATIONS

Cough Drop (Lozenges):

Instructions: Cook sugar and glucose syrup to 140-150°C; Add menthol, eucalyptus oil, and other ingredients; Pour into molds; Cool and package.

Topical Analgesic Cream (100 g):

Instructions: Melt menthol in oil phase; Mix with other active ingredients; Emulsify with base; Cool with mixing.

Mouthwash (1 L):

Instructions: Dissolve menthol and thymol in ethanol; Add glycerin and water; Mix well.

SECTION 9: USAGE INSTRUCTIONS

General Dosing Guide:

Instructions:

1. Dissolution: Dissolve menthol crystals in alcohol, propylene glycol, or oil phase; Heat if necessary (up to 40-50°C).

2. Addition: Add to formulation at the appropriate stage; For emulsions, dissolve in oil phase; For aqueous systems, use solubilizer (ethanol, propylene glycol).

3. Storage: Protect from light and heat; Keep tightly closed; Store in a cool, dry place.

SECTION 10: QUALITY SPECIFICATIONS

SECTION 11: TOXICOLOGICAL PROFILE

SECTION 12: GHS CLASSIFICATION AND LABELING

GHS Classification (in accordance with CLP and UN GHS):

Signal Word: WARNING

Hazard Pictograms: GHS07 (Exclamation Mark)

Hazard Statements (H-Codes):

NFPA 704 Hazard Classification:

SECTION 13: PRECAUTIONARY STATEMENTS (P-CODES)

SECTION 14: FIRST AID MEASURES

SECTION 15: FIREFIGHTING MEASURES

SECTION 16: STORAGE AND SHELF LIFE

SECTION 17: PACKAGING OPTIONS

SECTION 18: TRANSPORT INFORMATION

SECTION 19: REGULATORY STATUS

SECTION 20: OTHER NAMES AND SYNONYMS

SECTION 21: SUMMARY TABLE

SECTION 22: CRITICAL WARNINGS AND BEST PRACTICES

CRITICAL WARNINGS:

• Not highly toxic – but may cause skin and eye irritation. Wear protective equipment.

• Sublimes at room temperature – volatile; Keep container tightly closed.

• Light and heat sensitive – protect from direct sunlight and high temperatures.

• Flammable solid – keep away from open flames and high heat.

• May cause allergic reactions in sensitive individuals (contact dermatitis).

• High doses may cause gastrointestinal irritation; Avoid ingestion of large quantities.

• Do not apply to broken skin – may cause irritation; Avoid eye contact (cooling sensation may be painful).

• Not to be used on infants – may cause respiratory depression.

• May cause respiratory irritation in high concentrations – use in well-ventilated areas.

• GRAS status – safe for food and pharmaceutical use at recommended levels.

BEST PRACTICE RECOMMENDATIONS:

Pharmaceutical Applications: Use as active ingredient in cough syrups (0.5-2%), throat lozenges (0.5-2%), nasal sprays (0.5-5%), topical analgesics (2-10%); Provides cooling, decongestant, and soothing effects; Dissolve in alcohol or propylene glycol before addition.

Oral Care: Use as flavoring and cooling agent in toothpaste (0.1-0.5%), mouthwash (0.05-0.15%); Provides fresh breath; Antibacterial effect; Dissolve in alcohol for mouthwash formulations.

Cosmetics & Personal Care: Use as cooling and soothing agent in lotions, creams, lip balms, shampoos, and conditioners; Dosage 0.1-2.0%; Dissolve in oil phase before emulsification; Provides refreshing feeling.

Food & Beverage: Use as flavoring and cooling agent in chewing gum, candy, chocolate, mints, beverages, and ice cream; Dosage 0.1-1.0%; Add during cooking/mixing; Protect from heat where possible.

Aromatherapy: Use as refreshing and calming agent; Essential oil blends; Inhalers; Massage oils; Dosage depends on formulation.

Handling: Use in well-ventilated areas; Avoid dust formation; Use dust masks (N95/FFP2) when handling powder; Use gloves and safety goggles; Wash hands thoroughly after handling.

Personal Protective Equipment: Dust mask (N95/FFP2 or higher), safety goggles, protective gloves (nitrile, neoprene). Not required for solution handling.

Hygiene: Wash hands thoroughly after handling; Do not eat, drink, or smoke while using.

Storage: Store in tightly closed, light-proof containers; Store in a cool, dry, well-ventilated area; Protect from light, heat, and moisture; Opened containers must be resealed immediately; Shelf life: 24-48 months under proper conditions.

Spill Management: Sweep or vacuum (HEPA) and place in suitable sealed container; Avoid dust formation; Do not allow entry into drains or waterways.

Disposal: Dispose of in accordance with local, regional, and national regulations; Non-hazardous waste; Biodegradable; Can be incinerated in compliance with regulations.

MECHANISM OF COOLING EFFECT:

Menthol activates TRPM8 (cold-sensitive) receptors:

• TRPM8 Activation: TRPM8 is a cation channel on sensory neurons; Activated by cold temperatures and menthol; Increases intracellular calcium; Causes sensation of coolness.

• No Actual Temperature Change: Menthol does not lower skin temperature; The cooling sensation is a neurological effect; Potency varies among isomers (L-menthol is most active).

• Therapeutic Effects: Provides relief for muscle pain; Reduces itch; Acts as counterirritant; Local anesthetic effect.

HEALTH AND SAFETY NOTES:

LEGAL DISCLAIMER:
The information provided in this document is based on our current knowledge and experience and is presented in good faith. However, as all conditions of use are beyond our control, it does not constitute a binding specification or warranty. This Technical Data Sheet is for informational purposes only. Users are responsible for testing the suitability for their own applications. For complete safety, storage, use, handling, waste, and regulatory compliance information, please refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier.