L-Menthol, with the CAS number 2216-51-5, is a naturally occurring compound found in mint oils, particularly in peppermint and spearmint. It is widely used in various products for its cooling and refreshing properties. 

1. Chemical Formula: C10H20O
2. Molecular Weight: 156.27 g/mol
3. Physical Appearance: L-Menthol is a white crystalline solid at room temperature with a characteristic minty aroma.
4. Source: It is extracted from the essential oils of mint plants, primarily peppermint and spearmint.
5. Properties: L-Menthol produces a cooling sensation on the skin and mucous membranes due to its ability to trigger cold-sensitive receptors.
6. Uses: It is used in a variety of products such as cosmetics, personal care products, pharmaceuticals, and food products for its cooling, soothing, and refreshing effects. It is commonly found in products like balms, lotions, toothpaste, and chewing gum.
7. Health Benefits: L-Menthol is known for its analgesic, anti-inflammatory, and decongestant properties, which make it useful in products for pain relief, muscle relaxation, and respiratory health.
8. Safety: When used in appropriate concentrations, L-Menthol is generally safe for topical application. However, it can cause irritation in high concentrations or sensitive individuals.
9. Regulation: The use of L-Menthol in consumer products is regulated by various authorities to ensure its safety and proper use.

L-Menthol is a versatile ingredient that provides a refreshing and invigorating sensation in a wide range of products, contributing to its popularity in the cosmetic, pharmaceutical, and food industries.