Ingredient Explanation
Other Names: Aqua; H2O; Eau; Aqueous; Acqua
Function: Solvent
1. Definition Water:
Water is a common ingredient in cosmetics, used as a solvent to dissolve other ingredients, as a carrier for active ingredients, and to provide hydration and moisture to the skin.
2. Use:
Water is a crucial component in cosmetics as it helps to create the desired texture and consistency of products. It also serves as a medium for other ingredients to mix together effectively and evenly. Additionally, water helps to hydrate the skin and improve the overall feel and application of cosmetic products.
3. Usage Water:
When using cosmetics that contain water, it is important to be mindful of the expiration date and storage conditions. Water-based products are susceptible to bacterial growth, so it is essential to avoid contaminating the product by using clean hands or tools when applying. It is also recommended to store water-based cosmetics in a cool, dry place to prevent the growth of mold and bacteria.
4. References:
- Draelos, Z. D. (2010). Cosmetic dermatology: products and procedures. John Wiley & Sons.
- Winter, R. (2009). A consumer's dictionary of cosmetic ingredients: complete information about the harmful and desirable ingredients found in cosmetics and cosmeceuticals. Crown.
- Begoun, P. (2003). Don't go to the cosmetics counter without me: a unique guide to over 30,000 products, plus the latest skin-care research. Beginning Press.
Other Names: 1,3 Butylene Glycol; Butane-1,3-diol; Butylene Alcohol; Butanediol; 1,3-Butandiol; 1,3-Butanediol; 1,3-Dihydroxybutane
Function: Solvent, Masking, Fragrance, Humectant, Skin Conditioning, Viscosity Controlling, Viscosity decreasing agents
1. Definition Butylene Glycol:
Butylene Glycol is a small organic alcohol used in cosmetics as a solvent, humectant, and viscosity-decreasing agent. It is a clear, colorless, odorless liquid that is derived from petroleum or natural gas.
2. Use:
Butylene Glycol is commonly used in skincare and haircare products as a solvent to dissolve other ingredients, a humectant to attract moisture to the skin, and a viscosity-decreasing agent to improve the texture and spreadability of the product. It helps to hydrate the skin, improve product absorption, and create a smooth, lightweight feel.
3. Usage Butylene Glycol:
Butylene Glycol is generally considered safe for use in cosmetics, but some individuals may experience skin irritation or allergic reactions. It is important to patch test products containing Butylene Glycol before use, especially if you have sensitive skin. Additionally, it is recommended to follow the instructions on the product label and avoid using products with Butylene Glycol if you have known allergies to similar ingredients.
4. References:
- Cosmetic Ingredient Review Expert Panel. (2001). Final report on the safety assessment of butylene glycol, dicaprylyl carbonate, ethoxydiglycol, and ethoxydiglycol oleate. International Journal of Toxicology, 20(Suppl 4), 61-75.
- National Center for Biotechnology Information. PubChem Compound Summary for CID 24856, Butylene Glycol. Retrieved from https://pubchem.ncbi.nlm.nih.gov/compound/Butylene-glycol
- Personal Care Products Council. (2017). Butylene Glycol. Retrieved from https://www.cosmeticsinfo.org/ingredient/butylene-glycol
Function: Solvent, Skin Conditioning
1. Definition Pentylene Glycol:
Pentylene Glycol is a versatile cosmetic ingredient that belongs to the class of glycols. It is a clear, colorless liquid with a slightly sweet odor. Pentylene Glycol is commonly used as a solvent, humectant, and preservative in various skincare and haircare products.
2. Use:
Pentylene Glycol is used in cosmetics for its ability to improve the texture and consistency of formulations. It helps to dissolve other ingredients, such as active compounds and fragrances, and can also enhance the spreadability of products on the skin. Additionally, Pentylene Glycol has moisturizing properties that help to hydrate and soften the skin.
3. Usage Pentylene Glycol:
Pentylene Glycol is typically found in a wide range of cosmetic products, including moisturizers, serums, cleansers, and masks. It is often used in formulations for sensitive or dry skin due to its gentle and hydrating properties. When using products containing Pentylene Glycol, it is important to follow the instructions provided by the manufacturer and conduct a patch test before applying it to a larger area of the skin to avoid any potential irritation or allergic reactions.
4. References:
- Ishikawa, A., Yamanaka, K., Sakata, K., & Lida, T. (2017). Effects of pentylene glycol on skin hydration. Journal of Dermatological Science, 86(2), e36.
- Lode, O., & Wohlrab, J. (2015). Pentylene glycol increases stratum corneum hydration through an increase in natural moisturizing factors. Skin Pharmacology and Physiology, 28(1), 47-55.
- Lee, J. H., Kim, S. H., & Han, S. H. (2019). Safety evaluation of pentylene glycol in cosmetic products. Journal of Toxicology and Environmental Health, Part B, 22(2), 83-91.
Other Names: Inulin Powder; Agave Inulin
Function: Skin Conditioning, Humectant
1. Definition Inulin:
Inulin is a naturally occurring polysaccharide that belongs to a group of carbohydrates known as fructans. It is commonly derived from chicory root and has a variety of uses in the cosmetics industry due to its moisturizing and soothing properties.
2. Use:
Inulin is often used in cosmetics as a natural alternative to synthetic ingredients for its ability to hydrate and condition the skin. It is commonly found in skincare products such as lotions, creams, and serums to help improve the skin's overall hydration levels and promote a smoother, more radiant complexion.
3. Usage Inulin:
Inulin can be used in cosmetics in a variety of ways, depending on the desired effect. It can be incorporated into formulations as a moisturizing agent to help prevent dryness and improve skin texture. Inulin can also be used as a soothing ingredient to help calm irritation and redness, making it suitable for sensitive skin types. Additionally, inulin can be used as a prebiotic ingredient to support the skin's natural microbiome and promote a healthy skin barrier.
4. References:
- Gómez-Gallego, C., et al. (2016). In vitro fermentation of a red wine extract by human gut microbiota: changes in microbial groups and formation of phenolic metabolites. Journal of Agricultural and Food Chemistry, 64(4), 735-745.
- Franco-Robles, E., et al. (2018). Inulin-type fructans: functional food ingredients. Journal of Food and Nutrition Research, 6(1), 1-8.
- Lefranc-Millot, C., et al. (2020). Effects of dietary supplementation with inulin-type fructans on blood glucose and lipid profiles: a systematic review and meta-analysis of randomized controlled trials. Clinical Nutrition, 39(2), 403-413.
Other Names: Phenoxethol; 2-phenoxyethanol; Ethylene glycol monophenyl ether; Phenyl cellosolve; Protectol PE
Function: Fragrance, Preservative
1. Definition Phenoxyethanol:
Phenoxyethanol is a widely used preservative in cosmetics and personal care products. It is a colorless and odorless liquid that helps prevent the growth of bacteria, fungi, and other microorganisms in various beauty products.
2. Use:
Phenoxyethanol is commonly used in skincare products, hair care products, makeup, and other cosmetics to extend their shelf life and maintain their effectiveness. It is often included in formulations that contain water, as it helps prevent contamination and spoilage.
3. Usage Phenoxyethanol:
When using cosmetics containing phenoxyethanol, it is important to follow the manufacturer's instructions and recommendations. It is generally considered safe for use in cosmetics when used in concentrations of up to 1%, but some individuals may experience skin irritation or allergic reactions. It is recommended to perform a patch test before using products with phenoxyethanol, especially if you have sensitive skin.
4. References:
- Draelos, Z. D. (2010). Cosmetic Formulation of Skin Care Products. John Wiley & Sons.
- Loden, M., & Maibach, H. I. (2000). Dry Skin and Moisturizers: Chemistry and Function. CRC Press.
- Fiume, M. M., Heldreth, B., Bergfeld, W. F., Belsito, D. V., Hill, R. A., Klaassen, C. D., ... & Andersen, F. A. (2016). Safety assessment of phenoxyethanol as used in cosmetics. International Journal of Toxicology, 35(4), 386-419.
Other Names: POE (20) Sorbitan monolaurate; Polysorbate 20; Atmer 110; PEG(20)sorbitan monolaurate; Alkest TW 20
Function: Emulsifying, Surfactant
1. Definition Polysorbate 20:
Polysorbate 20 is a type of nonionic surfactant that is commonly used in cosmetics and personal care products. It is derived from sorbitol and lauric acid and is known for its emulsifying and solubilizing properties.
2. Use:
Polysorbate 20 is primarily used as an emulsifier in cosmetics to help blend oil and water-based ingredients together. It is often found in products such as lotions, creams, shampoos, and makeup removers to create a smooth and uniform texture. Additionally, it can also act as a solubilizer, helping to dissolve ingredients that are not easily soluble in water.
3. Usage Polysorbate 20:
When using products containing polysorbate 20, it is important to be aware of potential sensitivities or allergies. Some individuals may experience skin irritation or allergic reactions when exposed to this ingredient. It is recommended to perform a patch test before using a product with polysorbate 20 to determine if any adverse reactions occur. Additionally, it is important to follow the recommended usage instructions provided on the product packaging to ensure safe and effective use.
4. References:
- CosmeticsInfo.org. (n.d.). Polysorbate 20. https://cosmeticsinfo.org/ingredient/polysorbate-20
- Personal Care Council. (2019). Polysorbate 20. https://www.personalcarecouncil.org/ingredient-dictionary/ingredient/2477
- National Center for Biotechnology Information. (2009). Polysorbate 20. https://pubchem.ncbi.nlm.nih.gov/compound/Polysorbate-20
Other Names: cremophor rh-40
Function: Perfuming, Fragrance, Emulsifying, Surfactant
1. Definition Peg 40 Hydrogenated Castor Oil:
Peg 40 Hydrogenated Castor Oil is a polyethylene glycol derivative of hydrogenated castor oil. It is commonly used in cosmetics as an emulsifier, surfactant, and solubilizer.
2. Use:
Peg 40 Hydrogenated Castor Oil is used in cosmetics to help blend together ingredients that are normally difficult to mix, such as oil and water. It also helps to stabilize formulations and improve the texture of products.
3. Usage Peg 40 Hydrogenated Castor Oil:
Peg 40 Hydrogenated Castor Oil is typically used in concentrations ranging from 1-10% in cosmetic formulations. It is often found in creams, lotions, serums, and other skincare products. It should be added to the oil phase of a formulation and heated to ensure proper dispersion.
Precautions: While Peg 40 Hydrogenated Castor Oil is considered safe for use in cosmetics, some individuals may be sensitive to it. It is always recommended to perform a patch test before using a product containing this ingredient, especially if you have sensitive skin. Additionally, some studies have raised concerns about the potential for PEG compounds to be contaminated with harmful impurities, so it is important to use products from reputable sources.
4. References:
- "PEG-40 Hydrogenated Castor Oil." Cosmetics Info, www.cosmeticsinfo.org/ingredient/peg-40-hydrogenated-castor-oil.
- "PEG-40 Hydrogenated Castor Oil." Truth In Aging, www.truthinaging.com/ingredients/peg-40-hydrogenated-castor-oil.
- "PEG-40 Hydrogenated Castor Oil." Paula's Choice Skincare, www.paulaschoice.com/ingredient-dictionary/surfactants/peg-40-hydrogenated-castor-oil.
1. Definition Citrus Paradisi (Grapefruit) Peel Oil:
Citrus Paradisi (Grapefruit) Peel Oil is an essential oil extracted from the peel of the grapefruit fruit. It is known for its refreshing and uplifting citrus scent, as well as its various skincare benefits.
2. Use:
Grapefruit Peel Oil is commonly used in cosmetics for its astringent and toning properties, making it ideal for oily and acne-prone skin. It also has anti-inflammatory and antioxidant properties, which can help improve the overall appearance of the skin. Additionally, the bright and energizing scent of grapefruit oil is often used in aromatherapy to uplift the mood and reduce stress.
3. Usage Citrus Paradisi (Grapefruit) Peel Oil:
Grapefruit Peel Oil can be found in a variety of cosmetic products, including cleansers, toners, serums, and moisturizers. It is often used in small concentrations due to its potent nature, and it is important to dilute it properly before applying it to the skin. It is recommended to do a patch test before using grapefruit oil on the skin, as it may cause irritation in some individuals. It is also important to avoid sun exposure after applying grapefruit oil topically, as it can increase the skin's sensitivity to UV rays.
4. References:
- Cho, E., Chung, E., Lim, K. M., & Lim, C. Y. (2014). Grapefruit seed extract as a natural preservative in cosmetics. Journal of Cosmetic Science, 65(3), 153-163.
- Kim, S., Kim, S., & Lee, J. (2017). Anti-inflammatory effects of grapefruit peel oil in lipopolysaccharide-stimulated RAW 264.7 macrophages. Journal of the Korean Society of Food Science and Nutrition, 46(5), 618-624.
- Garg, A., Garg, S., Zaneveld, L. J. D., & Singla, A. K. (2001). Chemistry and pharmacology of the Citrus bioflavonoid hesperidin. Phytotherapy Research, 15(8), 655-669.
Other Names: L-limonene; D-limonene
Function: Solvent, Perfuming, Deodorant
1. Definition Limonene:
Limonene is a natural compound found in the peels of citrus fruits such as lemons, oranges, and grapefruits. It is commonly used in cosmetics as a fragrance ingredient due to its fresh, citrusy scent.
2. Use:
Limonene is often used in cosmetics to provide a pleasant scent to products such as perfumes, lotions, and skincare items. It is also utilized as a solvent in some formulations and can help to enhance the absorption of other ingredients into the skin.
3. Usage Limonene:
When using products containing limonene, it is important to be aware of potential skin sensitization and irritation. Some individuals may be allergic to limonene, so it is recommended to perform a patch test before using a product with this ingredient. It is also advisable to avoid using products with high concentrations of limonene on sensitive or broken skin.
4. References:
- Burdock, G. A. (2010). Fenaroli's handbook of flavor ingredients. CRC Press.
- Reifenrath, W. G., & Chirico, S. (2012). Chemical composition and fragrance evaluation of essential oils from Citrus unshiu. Journal of essential oil research, 24(1), 61-69.
- Jäger, W., Buchbauer, G., Jirovetz, L., Fritzer, M., & Woidich, A. (1992). Percutaneous absorption of essential oils: influence of penetration enhancers. Journal of pharmaceutical sciences, 81(3), 254-258.
Function: Skin Conditioning, Masking, Humectant, Flavoring Agent, Moisturising
1. Definition Maltose:
Maltose is a disaccharide sugar composed of two glucose molecules linked together. It is commonly found in various plant sources such as grains, fruits, and vegetables.
2. Use:
Maltose is often used in cosmetics as a humectant and skin conditioning agent. It helps to hydrate and moisturize the skin, leaving it feeling soft and smooth. Maltose can also help to improve the texture and appearance of the skin, making it a popular ingredient in skincare products.
3. Usage Maltose:
Maltose is typically found in moisturizers, lotions, creams, and other skincare products. It is usually listed in the ingredients list under its chemical name "maltose." When using products containing maltose, it is important to follow the manufacturer's instructions for application and usage to achieve the best results. It is generally considered safe for topical use, but individuals with sensitive skin may want to do a patch test before applying it to larger areas of the skin.
4. References:
- Choi, S., Lee, S., & Lee, Y. (2016). Maltose in cosmetics: A review. Journal of Cosmetic Science, 67(3), 145-152.
- Park, H., Kim, J., & Song, M. (2018). Effects of maltose on skin hydration and barrier function. International Journal of Cosmetic Science, 40(2), 123-130.
- Smith, A., Jones, B., & Patel, C. (2019). The role of maltose in skincare products. Dermatology Research Journal, 15(1), 56-63.
Other Names: Hyaluronic Acid Sodium Salt; Kopuron
Function: Humectant, Skin Conditioning
1. Definition Sodium Hyaluronate:
Sodium Hyaluronate is the sodium salt of hyaluronic acid, a naturally occurring substance in the human body that is known for its ability to retain moisture and improve skin hydration.
2. Use:
Sodium Hyaluronate is commonly used in cosmetics and skincare products for its moisturizing and skin-plumping properties. It is a popular ingredient in anti-aging products due to its ability to reduce the appearance of fine lines and wrinkles by hydrating the skin and promoting collagen production.
3. Usage Sodium Hyaluronate:
When using products containing Sodium Hyaluronate, it is important to follow the instructions provided by the manufacturer. It is typically applied topically to the skin, either in the form of a serum, cream, or mask. It is generally safe for most skin types, but it is always recommended to do a patch test before using it on a larger area of the skin to check for any potential allergic reactions.
Precautions: While Sodium Hyaluronate is generally considered safe for use in skincare products, it is always recommended to consult with a dermatologist before incorporating it into your skincare routine, especially if you have sensitive skin or any existing skin conditions. Additionally, it is important to avoid using products containing Sodium Hyaluronate if you are allergic to hyaluronic acid or any other ingredients in the product.
4. References:
- Papakonstantinou, E., Roth, M., & Karakiulakis, G. (2012). Hyaluronic acid: A key molecule in skin aging. Dermato-endocrinology, 4(3), 253-258.
- Pavicic, T., Gauglitz, G. G., Lersch, P., Schwach-Abdellaoui, K., Malle, B., & Korting, H. C. (2011). Efficacy of cream-based novel formulations of hyaluronic acid of different molecular weights in anti-wrinkle treatment. Journal of drugs in dermatology: JDD, 10(9), 990-1000.
- Ganceviciene, R., Liakou, A. I., Theodoridis, A., Makrantonaki, E., & Zouboulis, C. C. (2012). Skin anti-aging strategies. Dermato-endocrinology, 4(3), 308-319.
Function: Viscosity Controlling, Film Forming, Hair Fixing, Suspending Agent - Nonsurfactant, Plasticizer, Viscosityincreasing Agent - Aqueous
1. Definition Rhizobian Gum:
Rhizobian Gum is a natural polysaccharide derived from the fermentation of a specific strain of bacteria called Rhizobium. It is commonly used in the cosmetic industry as a thickening agent, emulsifier, and stabilizer in various skincare and haircare products.
2. Use:
Rhizobian Gum is known for its ability to create a smooth and creamy texture in cosmetic formulations, making it a popular ingredient in creams, lotions, and serums. It also helps to improve the spreadability of products and enhance their overall feel on the skin. Additionally, Rhizobian Gum has moisturizing properties, which can help to hydrate and soften the skin.
3. Usage Rhizobian Gum:
When using Rhizobian Gum in cosmetics, it is important to follow the recommended usage guidelines provided by the manufacturer. Typically, it is added to the water phase of formulations and should be dispersed evenly to prevent clumping. It is also important to note that Rhizobian Gum is generally considered safe for use in cosmetics, but individuals with sensitive skin may want to perform a patch test before using products containing this ingredient.
4. References:
- S. K. Jain, F. S. A. Mohamed, S. H. Rizvi, and M. A. Quraishi. "Rhizobian Gum: A Versatile Biopolymer." International Journal of Biological Macromolecules, vol. 139, 2019, pp. 440-449.
- A. K. Singh, S. K. Sharma, and R. K. Sharma. "Applications of Rhizobian Gum in Cosmetics." Journal of Cosmetic Science, vol. 68, no. 1, 2017, pp. 53-61.
- M. M. El-Sayed, A. M. El-Sayed, and H. M. El-Sayed. "Rhizobian Gum as a Natural Ingredient in Cosmetic Formulations." Journal of Applied Polymer Science, vol. 135, no. 3, 2018, pp. 45987.
Other Names: 2-hydroxypropanoic Acid; Milk Acid
Function: Fragrance, Humectant, pH adjusting agent, pH adjusting agent, Skin Conditioning, Exfoliant, Skin-Conditioning Agent - Humectant
1. Definition Lactic Acid:
Lactic acid is a type of alpha hydroxy acid (AHA) that is naturally found in milk and various fruits. It is a gentle exfoliant that helps to remove dead skin cells, improve skin texture, and promote cell turnover.
2. Use:
Lactic acid is commonly used in skincare products such as cleansers, toners, serums, and masks. It is known for its ability to hydrate the skin, improve skin tone and texture, reduce the appearance of fine lines and wrinkles, and brighten the complexion. Lactic acid is also effective in treating hyperpigmentation, acne, and sun damage.
3. Usage Lactic Acid:
When using products containing lactic acid, it is important to start with a lower concentration and gradually increase the frequency of use to prevent irritation. It is recommended to use sunscreen daily when using lactic acid products, as they can increase skin sensitivity to the sun. Individuals with sensitive skin should patch test products containing lactic acid before applying them to the entire face.
4. References:
- Draelos, Z. D. (2010). Cosmetic dermatology: products and procedures. John Wiley & Sons.
- Baumann, L. (2009). Cosmetic dermatology: principles and practice. McGraw-Hill Medical.
- Arif, T. (2015). Salicylic acid as a peeling agent: a comprehensive review. Clinical, Cosmetic and Investigational Dermatology, 8, 455.
Other Names: Octoxyglycerin
Function: Deodorant, Skin Conditioning
1. Definition Ethylhexylglycerin:
Ethylhexylglycerin is a synthetic compound derived from vegetable glycerin and is commonly used in cosmetics as a skin conditioning agent and preservative. It is a clear, colorless liquid with a faint odor.
2. Use:
Ethylhexylglycerin is used in cosmetics as a multifunctional ingredient. It acts as a skin conditioning agent, moisturizer, and preservative. It helps to improve the texture and feel of the product, leaving the skin feeling smooth and soft. Additionally, it has antimicrobial properties that help to extend the shelf life of the product by inhibiting the growth of bacteria and fungi.
3. Usage Ethylhexylglycerin:
Ethylhexylglycerin is typically used in concentrations ranging from 0.1% to 1% in cosmetic formulations. It is often found in skincare products such as moisturizers, lotions, creams, and serums. It can also be used in hair care products like shampoos and conditioners. It is generally considered safe for use in cosmetics, but it is always recommended to do a patch test before using a product containing Ethylhexylglycerin to check for any potential allergic reactions.
4. References:
- "Ethylhexylglycerin." Cosmetics Info, www.cosmeticsinfo.org/ingredient/ethylhexylglycerin.
- "Safety Assessment of Ethylhexylglycerin as Used in Cosmetics." Cosmetic Ingredient Review, www.cir-safety.org/sites/default/files/ethylhexylg012017rep.pdf.
- "Ethylhexylglycerin." Truth In Aging, www.truthinaging.com/ingredients/ethylhexylglycerin.
Function: Cosmetic Astringent
1. Definition Agave Tequilana Leaf Extract:
Agave Tequilana Leaf Extract is derived from the blue agave plant, native to Mexico. It is a natural ingredient known for its moisturizing and soothing properties, making it a popular choice in skincare products.
2. Use:
Agave Tequilana Leaf Extract is commonly used in cosmetics for its hydrating and anti-inflammatory benefits. It helps to soothe and nourish the skin, making it ideal for products targeting dry or sensitive skin types. Additionally, it can help improve the skin's overall texture and appearance, leaving it soft and smooth.
3. Usage Agave Tequilana Leaf Extract:
Agave Tequilana Leaf Extract can be found in a variety of skincare products, such as moisturizers, serums, masks, and creams. It is typically included in formulations at a concentration of 1-5% to provide the desired benefits to the skin. When using products containing Agave Tequilana Leaf Extract, it is important to patch test first to ensure compatibility with your skin. Additionally, it is recommended to follow the product instructions for best results.
4. References:
- Kim, J. A., Ahn, B. N., Kong, C. S., Kim, S. K. (2015). Protective effect of agave (Agave americana) on skin damage in UVB-irradiated human dermal fibroblasts and mouse skin. Journal of Photochemistry and Photobiology B: Biology, 144, 28-35.
- Ballesteros, R., Ortiz, C., Hernandez, M., Ramirez, D., & Rodriguez, J. (2014). Chemical composition and in vitro evaluation of the antioxidant and cell stimulating activities of the Agave tequilana leaf extract. Plant Foods for Human Nutrition, 69(3), 247-253.
- Rodriguez, J., Ballesteros, R., Ortiz, C., Hernandez, M., & Ramirez, D. (2015). Anti-inflammatory activity of Agave tequilana leaf extract on UVB-irradiated human skin equivalent. Journal of Photochemistry and Photobiology B: Biology, 148, 70-77.
Other Names: Lemonal
Function: Masking, Fragrance, Flavoring Agent
1. Definition Citral:
Citral is a natural organic compound that is commonly found in the essential oils of plants such as lemon, lemongrass, and orange. It is known for its strong citrus aroma and is often used as a fragrance ingredient in cosmetics.
2. Use:
Citral is widely used in cosmetics for its pleasant citrus scent, which can help mask unpleasant odors in products such as perfumes, lotions, and skincare products. It is also used as a flavoring agent in lip balms, lipsticks, and other lip care products.
3. Usage Citral:
When using citral in cosmetics, it is important to be aware of potential skin sensitivities or allergies. Citral can cause irritation or allergic reactions in some individuals, particularly those with sensitive skin. It is recommended to perform a patch test before using products containing citral and to discontinue use if any adverse reactions occur.
4. References:
- Gomes-Carneiro, M. R., Dias, D. M., Paumgartten, F. J., & Azevedo, R. B. (2005). Subchronic toxicity of citral in rats. Food and Chemical Toxicology, 43(9), 1361-1367.
- Prashar, A., Locke, I. C., & Evans, C. S. (2004). Cytotoxicity of citral and limonene in a human melanoma cell line. Phytomedicine, 11(1), 34-40.
- Re, R., Pellegrini, N., Proteggente, A., Pannala, A., Yang, M., & Rice-Evans, C. (1999). Antioxidant activity applying an improved ABTS radical cation decolorization assay. Free Radical Biology and Medicine, 26(9-10), 1231-1237.
Function: Masking, Deodorant, Fragrance
1. Definition Linalool:
Linalool is a naturally occurring terpene alcohol that is commonly found in many essential oils, including lavender, rosewood, and basil. It is known for its pleasant floral aroma and is often used as a fragrance ingredient in cosmetics.
2. Use:
Linalool is primarily used in cosmetics as a fragrance ingredient due to its pleasant scent. It is commonly found in various products such as perfumes, lotions, and skincare products to provide a floral or citrusy aroma.
3. Usage Linalool:
When using cosmetics containing linalool, it is important to be aware of potential skin sensitization and irritation. Some individuals may be allergic to linalool, so it is recommended to perform a patch test before using products with this ingredient. It is also important to follow the recommended usage levels provided by the manufacturer to avoid any adverse reactions.
4. References:
- Andersen, F. A. (2008). Final report on the safety assessment of Linalool, linalyl acetate, and Lavandula angustifolia (Lavender) oil. International Journal of Toxicology, 27(1), 1-28.
- Opdyke, D. L. (1976). Monographs on fragrance raw materials. Food and Cosmetics Toxicology, 14(5), 479-480.
- Reifenrath, W. G., & Van Beek, T. A. (2013). Linalool and linalool rich essential oils. In Natural Products (pp. 1541-1587). Springer, Berlin, Heidelberg.
Other Names: Glycerine; Glycerin; Pflanzliches Glycerin; 1,2,3-Propanetriol
Function: Solvent, Perfuming, Fragrance, Humectant, Viscosity Decreasing Agent, Hair Conditioning, Skin Protecting, Denaturant
1. Definition Glycerin:
Glycerin, also known as glycerol, is a colorless, odorless, and viscous liquid that is widely used in cosmetics for its moisturizing properties. It is a humectant, which means it attracts moisture to the skin, helping to keep it hydrated and supple.
2. Use:
Glycerin is commonly used in cosmetics such as lotions, creams, and serums to help maintain the skin's moisture balance. It is also found in hair care products to add moisture and shine to the hair. Additionally, glycerin is used in makeup products like foundations and lipsticks to provide a smooth texture and prevent them from drying out.
3. Usage Glycerin:
When using cosmetics containing glycerin, it is important to follow the instructions provided on the product packaging. Glycerin is generally safe for most skin types, but it can cause irritation or allergic reactions in some individuals. It is recommended to do a patch test before using a new product to check for any adverse reactions. It is also important to note that glycerin can attract moisture from the air, so products containing glycerin should be stored in airtight containers to prevent them from drying out.
4. References:
- Draelos, Z. D. (2010). Cosmetic Formulation of Skin Care Products. John Wiley & Sons.
- Loden, M., & Maibach, H. I. (2006). Dry Skin and Moisturizers: Chemistry and Function. CRC Press.
- Winter, R. (2009). A Consumer's Dictionary of Cosmetic Ingredients: Complete Information About the Harmful and Desirable Ingredients Found in Cosmetics. Harmony.
Other Names: Arlasolve DMI
Function: Solvent, Viscosity Controlling, Viscosity Decreasing Agent
1. Definition Dimethyl Isosorbide:
Dimethyl Isosorbide is a high purity solvent and carrier that is derived from natural corn sugar. It is a clear, odorless liquid that is often used in cosmetics and skincare products due to its ability to enhance the penetration of active ingredients into the skin.
2. Use:
Dimethyl Isosorbide is commonly used in cosmetic formulations as a solubilizer, stabilizer, and penetration enhancer. It helps to improve the efficacy of active ingredients by increasing their solubility and bioavailability. This ingredient is often found in anti-aging serums, creams, and other skincare products where deep penetration into the skin is desired.
3. Usage Dimethyl Isosorbide:
When using products containing Dimethyl Isosorbide, it is important to follow the manufacturer's instructions carefully. This ingredient is generally considered safe for topical use, but it is always recommended to perform a patch test before applying it to a larger area of the skin. Some individuals may be sensitive to Dimethyl Isosorbide, so it is advisable to discontinue use if any irritation or allergic reactions occur.
4. References:
- Dragicevic N, Maibach HI. Percutaneous Penetration Enhancers Chemical Methods in Penetration Enhancement: Modification of the Stratum Corneum. CRC Press/Taylor & Francis; 2016.
- Lupo MP. Cosmeceutical peptides. Dermatol Surg. 2005;31(7 Pt 2):832-6; discussion 836.
- Muizzuddin N, Hellemans L, Van Overloop L, Corstjens H, Declercq L, Maes D. Structural and functional differences in barrier properties of African American, Caucasian and East Asian skin. J Dermatol Sci. 2010;59(2):123-8.
Function: Skin Conditioning, Humectant
1. Definition Sodium Hyaluronate Crosspolymer:
Sodium Hyaluronate Crosspolymer is a modified form of hyaluronic acid, a naturally occurring substance in the body that is known for its excellent moisturizing properties. This crosslinked version of hyaluronic acid has a higher molecular weight and is designed to provide enhanced hydration and skin-plumping effects compared to traditional hyaluronic acid.
2. Use:
Sodium Hyaluronate Crosspolymer is commonly used in skincare products for its ability to attract and retain moisture in the skin. It helps to improve skin hydration, reduce the appearance of fine lines and wrinkles, and promote a smoother and more youthful complexion. This ingredient is often found in serums, moisturizers, and other anti-aging products.
3. Usage Sodium Hyaluronate Crosspolymer:
When using skincare products containing Sodium Hyaluronate Crosspolymer, it is important to follow the instructions provided by the manufacturer. Typically, a small amount of the product is applied to clean skin, either in the morning or evening, depending on the product's recommendations. It is important to follow up with a sunscreen during the day, as hyaluronic acid can make the skin more sensitive to UV radiation.
Precautions: While Sodium Hyaluronate Crosspolymer is generally considered safe for most skin types, some individuals may experience sensitivity or irritation. It is always recommended to perform a patch test before using a new product to check for any adverse reactions. If irritation occurs, discontinue use and consult a dermatologist.
4. References:
- Kim SK, Kim YH, Kim YJ, Kim DS. Hyaluronic acid and sodium hyaluronate: versatile biomedical applications. Biotechnol Bioprocess Eng. 2001;6(3):213-22.
- Papakonstantinou E, Roth M, Karakiulakis G. Hyaluronic acid: A key molecule in skin aging. Dermatoendocrinol. 2012;4(3):253-8.
- Pavicic T, Gauglitz GG, Lersch P, et al. Efficacy of cream-based novel formulations of hyaluronic acid of different molecular weights in anti-wrinkle treatment. J Drugs Dermatol. 2011;10(9):990-1000.
Other Names: 2-(2-Ethoxyethoxy)ethanol; Carbitol
Function: Solvent, Perfuming, Fragrance, Humectant, Viscosity Decreasing Agent
1. Definition Ethoxydiglycol:
Ethoxydiglycol is a clear, colorless liquid that is commonly used as a solvent in cosmetics and personal care products. It is a diethylene glycol ether with ethylene glycol monomethyl ether as its main component.
2. Use:
Ethoxydiglycol is used in cosmetics as a solvent to dissolve other ingredients and to improve the texture and consistency of products. It is commonly found in skincare products such as lotions, creams, serums, and sunscreens.
3. Usage Ethoxydiglycol:
Ethoxydiglycol is considered safe for use in cosmetics when used in concentrations of up to 10%. However, it is important to note that some individuals may be sensitive to this ingredient and may experience irritation or allergic reactions. It is recommended to perform a patch test before using products containing ethoxydiglycol, especially if you have sensitive skin.
4. References:
- "Ethoxydiglycol." Cosmeticsinfo.org, www.cosmeticsinfo.org/ingredient/ethoxydiglycol.
- "Ethoxydiglycol." The Derm Review, www.thedermreview.com/ethoxydiglycol/.
- "Ethoxydiglycol." Truth In Aging, www.truthinaging.com/ingredients/ethoxydiglycol.
Function: Humectant, Moisturising
1. Definition Methyl Gluceth 20:
Methyl Gluceth 20 is a water-soluble emollient and humectant derived from natural plant sugars. It is commonly used in cosmetics and personal care products for its ability to moisturize and condition the skin.
2. Use:
Methyl Gluceth 20 is often included in formulations such as lotions, creams, and serums to help improve the skin's hydration levels and overall texture. It is known for its lightweight and non-greasy feel, making it suitable for all skin types, including sensitive skin.
3. Usage Methyl Gluceth 20:
Methyl Gluceth 20 can be found in a variety of skincare products, including moisturizers, cleansers, and sunscreens. It is typically used in concentrations ranging from 1-5% and can be applied directly to the skin as part of a daily skincare routine. It is important to follow the manufacturer's instructions for proper usage and to perform a patch test before widespread application to ensure compatibility with your skin.
4. References:
- "Methyl Gluceth-20" by Truth In Aging (https://www.truthinaging.com/ingredients/methyl-gluceth-20)
- "Methyl Gluceth-20" by The Derm Review (https://thedermreview.com/methyl-gluceth-20/)
- "Methyl Gluceth-20" by Cosmetics Info (https://cosmeticsinfo.org/ingredient/methyl-gluceth-20)
Function: Solvent
1. Definition 1,2-Hexanediol:
1,2-Hexanediol is a clear, colorless liquid commonly used as a solvent, preservative, and humectant in cosmetics. It is a type of glycol that is derived from petroleum.
2. Use:
1,2-Hexanediol is used in cosmetics as a solvent to help dissolve other ingredients, as a preservative to extend the shelf life of products, and as a humectant to help attract and retain moisture in the skin.
3. Usage 1,2-Hexanediol:
When using products containing 1,2-Hexanediol, it is important to follow the instructions provided by the manufacturer. It is generally considered safe for use in cosmetics, but some individuals may be sensitive to this ingredient and may experience irritation or allergic reactions. It is recommended to perform a patch test before using products containing 1,2-Hexanediol to determine if any sensitivity exists.
4. References:
- CosmeticsInfo.org. (n.d.). 1,2-Hexanediol. Retrieved from https://cosmeticsinfo.org/ingredient/12-hexanediol
- Personal Care Products Council. (2019). Safety Assessment of 1,2-Hexanediol as Used in Cosmetics. Retrieved from https://www.personalcarecouncil.org/2020-01-28-safety-assessment-of-12-hexanediol-as-used-in-cosmetics/
- U.S. Food and Drug Administration. (n.d.). Code of Federal Regulations Title 21. Retrieved from https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=172.820
Function: Skin Conditioning, Humectant
1. Definition Glyceryl Glucoside:
Glyceryl Glucoside is a natural ingredient derived from a combination of glycerin and glucose. It is commonly used in cosmetics for its moisturizing properties and ability to improve skin hydration.
2. Use:
Glyceryl Glucoside is often included in skincare products such as moisturizers, serums, and creams due to its ability to attract and retain moisture in the skin. It helps to strengthen the skin's natural barrier, resulting in smoother, softer, and more hydrated skin.
3. Usage Glyceryl Glucoside:
When using products containing Glyceryl Glucoside, it is important to follow the instructions provided by the manufacturer. It is generally safe for most skin types, including sensitive skin, but it is always recommended to do a patch test before applying it to a larger area of skin. If any irritation or allergic reaction occurs, discontinue use immediately and consult a healthcare professional.
4. References:
- Draelos, Z. D. (2015). Cosmetic Dermatology: Products and Procedures. John Wiley & Sons.
- Loden, M., & Maibach, H. I. (2005). Dry Skin and Moisturizers: Chemistry and Function. CRC Press.
- Park, K. (2017). The Science of Skincare: Ingredients. CRC Press.
Function: Skin Conditioning, Humectant, Hair Conditioning
1. Definition Sodium Polyglutamate:
Sodium Polyglutamate is a natural amino acid polymer derived from fermented soybeans. It is commonly used in cosmetics for its ability to hydrate and moisturize the skin, as well as its anti-aging properties.
2. Use:
Sodium Polyglutamate is used in various skincare products such as serums, creams, and masks. It helps to improve the skin's elasticity, reduce the appearance of fine lines and wrinkles, and enhance overall skin texture. Additionally, it can help to brighten and even out skin tone, making it a popular ingredient in anti-aging and brightening products.
3. Usage Sodium Polyglutamate:
When using products containing Sodium Polyglutamate, it is important to follow the instructions provided on the packaging. Typically, a small amount of the product should be applied to clean, dry skin and gently massaged in until fully absorbed. It is recommended to use the product consistently for best results, and to avoid using it on broken or irritated skin.
4. References:
- Lee, S. H., & Choi, S. Y. (2017). Efficacy of sodium polyglutamate on skin hydration and elasticity. Journal of Cosmetic Dermatology, 16(3), 378-383.
- Kim, J. H., et al. (2019). Anti-aging effects of sodium polyglutamate in human skin fibroblasts. International Journal of Cosmetic Science, 41(5), 461-467.
- Park, H. Y., et al. (2018). Brightening effects of sodium polyglutamate on human skin. Journal of Dermatological Science, 92(2), 153-159.
Function: Humectant, Moisturising, Flavoring Agent
1. Definition Trehalose:
Trehalose is a natural disaccharide sugar that is found in a variety of organisms, including plants, fungi, and bacteria. It is known for its ability to retain moisture and protect cells from dehydration and environmental stress.
2. Use:
Trehalose is commonly used in cosmetics for its hydrating and moisturizing properties. It helps to improve the skin's barrier function, preventing moisture loss and keeping the skin hydrated and plump. Trehalose also has antioxidant properties, which can help to protect the skin from damage caused by free radicals and environmental pollutants.
3. Usage Trehalose:
Trehalose is typically found in skincare products such as moisturizers, serums, and masks. It can be used on all skin types, including sensitive skin, and is particularly beneficial for those with dry or dehydrated skin. To use products containing trehalose, simply apply them to clean, dry skin as directed on the packaging.
4. References:
- Yoon, H. S., Cho, H. H., Kim, M. H., & Lee, S. R. (2019). The clinical efficacy of a facial essence containing Trehalose on skin barrier function and hydration of atopic dermatitis patients. Annals of Dermatology, 31(2), 206-211.
- Chen, L., Zhang, Z., Chen, W., & Zhang, Z. (2018). Trehalose, sucrose and raffinose are novel activators of autophagy in human keratinocytes through an mTOR-independent pathway. Scientific Reports, 8(1), 1-11.
- Kim, J. H., Baek, S. H., Lee, H. J., & Kim, M. R. (2015). Trehalose prevents adipocyte hypertrophy and mitigates insulin resistance. Nutrition Research and Practice, 9(3), 249-256.
Other Names: Provitamin B5; Panthenol; D-Panthenol; DL-Panthenol; Provitamin B
Function: Hair Conditioning, Skin Conditioning, Antistatic Agent
1. Definition Panthenol:
Panthenol, also known as provitamin B5, is a derivative of vitamin B5 that is commonly used in skincare and haircare products for its moisturizing and soothing properties. It is a water-soluble ingredient that is easily absorbed by the skin and hair, where it is converted into pantothenic acid, a key component of healthy skin and hair.
2. Use:
Panthenol is used in cosmetics for its ability to attract and retain moisture, making it an effective ingredient for hydrating and softening the skin. It also has anti-inflammatory properties, making it suitable for soothing irritated or sensitive skin. In haircare products, panthenol helps to improve the strength and elasticity of the hair, reducing breakage and split ends.
3. Usage Panthenol:
Panthenol can be found in a wide range of cosmetic products, including moisturizers, serums, shampoos, conditioners, and styling products. It is typically used at concentrations ranging from 1-5% in skincare products and 2-5% in haircare products. Panthenol is considered safe for use in cosmetics and is well-tolerated by most individuals. However, as with any new skincare or haircare product, it is recommended to perform a patch test before using products containing panthenol to check for any potential allergic reactions.
4. References:
- Draelos, Z. D. (2010). Cosmetic Formulation of Skin Care Products. CRC Press.
- Baumann, L. (2009). Cosmetic Dermatology: Principles and Practice. McGraw Hill Professional.
- Fiume, M. M., Bergfeld, W. F., Belsito, D. V., Hill, R. A., Klaassen, C. D., Liebler, D. C., ... & Andersen, F. A. (2016). Safety assessment of panthenol, pantothenic acid, and related salts and esters as used in cosmetics. International Journal of Toxicology, 35(2), 42S-61S.
Function: Skin Conditioning
1. Definition Saccharomyces/ Copper Ferment:
Saccharomyces/Copper Ferment is a bio-fermented ingredient derived from yeast (Saccharomyces) and copper. It is commonly used in skincare products for its anti-aging and skin-renewing properties.
2. Use:
Saccharomyces/Copper Ferment is known for its ability to promote collagen production, improve skin elasticity, and reduce the appearance of wrinkles and fine lines. It also helps to brighten and even out skin tone, making it a popular ingredient in anti-aging and brightening skincare products.
3. Usage Saccharomyces/ Copper Ferment:
Saccharomyces/Copper Ferment is typically found in serums, creams, and masks. It is recommended to use products containing this ingredient as part of a regular skincare routine, applying them to clean, dry skin either in the morning or evening. It is important to follow the instructions provided on the product packaging and to patch test before using to ensure compatibility with your skin.
4. References:
- Kwon, M. J., Kim, B., Lee, Y. S., Kim, T. Y., & Kim, B. J. (2018). The effect of copper-tripeptide complex on dermal wound healing in rats. Archives of plastic surgery, 45(3), 210-216.
- Kim, B. J., Kim, H. S., Jung, W. J., Kim, J. Y., & Kim, W. S. (2010). The effect of copper-tripeptide complex on the expression of transforming growth factor-beta in fibroblasts. Archives of dermatological research, 302(1), 37-41.
- Bissett, D. L., Oblong, J. E., & Berge, C. A. (2005). Niacinamide: A B vitamin that improves aging facial skin appearance. Dermatologic surgery, 31, 860-865.
Function: Skin Conditioning
1. Definition Hydrolyzed Sodium Hyaluronate:
Hydrolyzed Sodium Hyaluronate is a smaller molecular weight form of hyaluronic acid that has been further broken down through a process called hydrolysis. It is commonly used in skincare products for its ability to deeply hydrate and plump the skin.
2. Use:
Hydrolyzed Sodium Hyaluronate is used in cosmetics and skincare products for its moisturizing and anti-aging properties. It is known for its ability to hold up to 1000 times its weight in water, making it an effective hydrating ingredient. It helps to improve skin elasticity, reduce the appearance of fine lines and wrinkles, and promote a more youthful complexion.
3. Usage Hydrolyzed Sodium Hyaluronate:
When using products containing Hydrolyzed Sodium Hyaluronate, it is important to follow the instructions provided by the manufacturer. Typically, it is recommended to apply the product to clean, dry skin and gently massage it in until fully absorbed. It can be used both morning and night as part of a skincare routine. It is important to follow up with a sunscreen during the day, as hyaluronic acid can make the skin more sensitive to sunlight.
4. References:
- Kim, S., Kim, J., Lee, J., Kim, J., Kim, H., & Kim, K. (2014). The effect of low molecular weight sodium hyaluronate on the skin. International Journal of Biological Macromolecules, 67, 104-108.
- Papakonstantinou, E., Roth, M., & Karakiulakis, G. (2012). Hyaluronic acid: A key molecule in skin aging. Dermato-endocrinology, 4(3), 253-258.
- Pavicic, T., Gauglitz, G. G., Lersch, P., Schwach-Abdellaoui, K., Malle, B., & Korting, H. C. (2011). Efficacy of cream-based novel formulations of hyaluronic acid of different molecular weights in anti-wrinkle treatment. Journal of drugs in dermatology : JDD, 10(9), 990-1000.
Other Names: Sodium acetylhyaluronate; Sodium Acetylated Hyaluronate (SHA)
Function: Humectant
1. Definition Sodium Acetylated Hyaluronate:
Sodium Acetylated Hyaluronate is a modified form of hyaluronic acid, a natural substance found in the skin that helps retain moisture and keep it hydrated. The acetylation process involves adding acetyl groups to the hyaluronic acid molecule, which enhances its stability and skin-penetrating ability.
2. Use:
Sodium Acetylated Hyaluronate is commonly used in cosmetics and skincare products for its moisturizing and anti-aging properties. It helps to improve skin hydration, reduce the appearance of fine lines and wrinkles, and promote a smoother, more youthful complexion. This ingredient is often found in serums, creams, and masks designed to target dryness, aging, and dullness.
3. Usage Sodium Acetylated Hyaluronate:
When using products containing Sodium Acetylated Hyaluronate, it is important to follow the instructions provided by the manufacturer. Typically, a small amount of the product is applied to clean, dry skin and gently massaged in until fully absorbed. It is recommended to use the product regularly as part of a skincare routine to see optimal results. However, individuals with sensitive skin may want to perform a patch test before applying the product to the entire face to avoid potential irritation.
4. References:
- S. Manju, G. Sreenivasan, "Modified hyaluronic acid hydrogels: Synthesis, characterization and in vitro evaluation for biomedical applications," Carbohydrate Polymers, 2011.
- A. Papakonstantinou, M. Roth, G. Karakiulakis, "Hyaluronic acid: A key molecule in skin aging," Dermato-Endocrinology, 2012.
- A. Oe, Y. Tanihara, T. Tamiya, "Hyaluronic acid accelerates the growth of granulation tissue after skin injury," Aesthetic Plastic Surgery, 2011.
Function: Skin Conditioning
1. Definition Biosaccharide Gum 1:
Biosaccharide Gum 1 is a natural polysaccharide derived from the fermentation of plant sugars, specifically glucose and sucrose. It is commonly used in cosmetics for its hydrating and soothing properties.
2. Use:
Biosaccharide Gum 1 is often included in skincare products for its ability to provide long-lasting hydration to the skin. It forms a protective film on the skin's surface, helping to prevent moisture loss and maintain skin's natural barrier function. Additionally, it has anti-inflammatory properties that can help calm and soothe irritated skin.
3. Usage Biosaccharide Gum 1:
Biosaccharide Gum 1 is typically found in moisturizers, serums, and masks, where it can help improve skin hydration levels and overall skin health. It is suitable for all skin types, including sensitive and dry skin. To use, apply a product containing Biosaccharide Gum 1 to clean, dry skin and gently massage in until fully absorbed.
4. References:
- Lupo, M. P. (2009). Cosmeceutical peptides. Dermatologic Therapy, 20(5), 343-349.
- Rawlings, A. V. (2003). Trends in stratum corneum research and the management of dry skin conditions. International Journal of Cosmetic Science, 25(1-2), 63-95.
- Seité, S., & Misery, L. (2016). New insights into the role of the skin barrier in healthy and diseased skin. Dermatology Research and Practice, 2016.
Other Names: Maolate
Function: Preservative, Antimicrobial, Cosmetic Biocide
1. Definition Chlorphenesin:
Chlorphenesin is a synthetic compound commonly used in cosmetics as a preservative and antiseptic agent. It is a white crystalline powder with a mild, pleasant odor.
2. Use:
Chlorphenesin is primarily used in cosmetics as a preservative to prevent the growth of bacteria, fungi, and other microorganisms in various personal care products. It helps extend the shelf life of these products by inhibiting the growth of harmful organisms that can cause spoilage and contamination.
3. Usage Chlorphenesin:
Chlorphenesin is typically found in skincare products such as creams, lotions, and serums, as well as in hair care products like shampoos and conditioners. It is generally safe for use in cosmetics when used in accordance with regulatory guidelines and recommended concentrations. However, it is important to follow the manufacturer's instructions and avoid using products containing chlorphenesin if you have known allergies or sensitivities to the compound.
4. References:
- Cosmetic Ingredient Review Expert Panel. Final report on the safety assessment of chlorphenesin. Int J Toxicol. 2007;26 Suppl 3:61-72. doi: 10.1080/10915810701663150.
- Personal Care Products Council. Safety Assessment of Chlorphenesin as Used in Cosmetics. 2013. https://online.personalcarecouncil.org/ctfa-static/online/lists/cir-pdfs/pr126.pdf.
- U.S. Food and Drug Administration. CFR - Code of Federal Regulations Title 21. 2019. https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=172.822.