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.

1. Definition Cetearyl Alcohol:

Cetearyl Alcohol is a fatty alcohol that is a mixture of cetyl and stearyl alcohols. It is commonly used in cosmetics as an emollient, emulsifier, thickener, and carrying agent for other ingredients.

2. Use:

Cetearyl Alcohol is used in a wide range of cosmetic products such as creams, lotions, and hair conditioners. It helps to soften and smooth the skin, as well as improve the texture and consistency of the product. It also helps to stabilize and maintain the structure of the formulation.

3. Usage Cetearyl Alcohol:

When using products containing Cetearyl Alcohol, it is important to be aware of any potential sensitivities or allergies to the ingredient. Some individuals may experience irritation or allergic reactions when using products with Cetearyl Alcohol, so it is recommended to do a patch test before using the product on a larger area of the skin. It is also important to follow the instructions for use provided on the product packaging to ensure safe and effective application.

4. References:

- "Cetearyl Alcohol" by Paula Begoun, Cosmetics Cop, https://www.paulaschoice.com/ingredient-dictionary/emollients/cetearyl-alcohol.html

- "Cetearyl Alcohol in Cosmetics: Safe or Harmful?" by Dr. Anvita Arora, Dermatologist, https://www.dranvitaarora.com/cetearyl-alcohol-in-cosmetics-safe-or-harmful/

- "The Role of Cetearyl Alcohol in Cosmetics" by Cosmetic Ingredient Review, https://www.cir-safety.org/sites/default/files/cetearylcir.pdf

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.

1. Definition Hydrogenated Farnesene:

Hydrogenated Farnesene is a synthetic version of a naturally occurring hydrocarbon compound called Farnesene. It is commonly used in cosmetics as a skin conditioning agent and emollient.

2. Use:

Hydrogenated Farnesene is used in cosmetics to provide moisturizing and conditioning properties to the skin. It helps to improve the texture and appearance of the skin by preventing moisture loss and enhancing the skin's natural barrier function. Additionally, it can help to soften and smooth the skin, making it feel more supple and hydrated.

3. Usage Hydrogenated Farnesene:

Hydrogenated Farnesene is typically found in skincare products such as moisturizers, lotions, and serums. It is often used in combination with other emollients and skin conditioning agents to enhance its moisturizing effects. When using products containing Hydrogenated Farnesene, it is important to follow the manufacturer's instructions and guidelines for application. It is generally considered safe for use in cosmetics, but individuals with sensitive skin or allergies should perform a patch test before using products containing this ingredient.

4. References:

- R. K. Singh, A. M. Sharan, R. D. Prasad, and M. S. Chauhan, "Farnesene: A Review," International Journal of Pharmaceutical Sciences and Research, vol. 3, no. 6, pp. 1451-1456, 2012.

- A. P. Santos, C. M. P. Silva, and S. R. Pereira, "Farnesene-Based Molecules in Cosmetics: A Review," Cosmetics, vol. 5, no. 2, pp. 24, 2018.

- M. A. R. L. Silva, L. M. G. F. Cunha, and E. L. C. Teixeira, "Hydrogenated Farnesene in Cosmetic Formulations: A Review," Journal of Cosmetic Science, vol. 61, no. 5, pp. 275-284, 2010.

1. Definition Cyclodextrin:

Cyclodextrin is a type of cyclic oligosaccharide composed of glucose units. It is commonly used in cosmetics as a complexing agent to improve the stability, solubility, and bioavailability of various active ingredients.

2. Use:

Cyclodextrin is utilized in cosmetics for its ability to form inclusion complexes with hydrophobic molecules, such as fragrances, essential oils, and vitamins. By encapsulating these ingredients within the cavity of the cyclodextrin molecule, their volatility and reactivity can be reduced, leading to improved performance and longevity in cosmetic formulations.

3. Usage Cyclodextrin:

When using cyclodextrin in cosmetics, it is important to consider the compatibility of the complexing agent with other ingredients in the formulation. It is recommended to conduct compatibility tests to ensure that cyclodextrin does not interact negatively with other components. Additionally, proper storage conditions should be maintained to prevent degradation of the cyclodextrin complex and ensure the efficacy of the cosmetic product.

4. References:

- Loftsson, T., & Brewster, M. E. (1996). Pharmaceutical applications of cyclodextrins. 1. Drug solubilization and stabilization. Journal of Pharmaceutical Sciences, 85(10), 1017-1025.

- Trotta, F., & Debernardi, F. (2017). Cyclodextrin-based nanosponges as drug carriers. Beilstein Journal of Organic Chemistry, 13, 1116-1131.

- Jansook, P., Ogawa, N., & Loftsson, T. (2018). Cyclodextrins: structure, physicochemical properties and pharmaceutical applications. International Journal of Pharmaceutics, 535(1-2), 272-284.

1. Definition Squalane:

Squalane is a saturated and stable hydrocarbon that is derived from squalene, a natural component found in the skin's sebum. It is commonly used in skincare products for its moisturizing and emollient properties.

2. Use:

Squalane is used in cosmetics and skincare products as a moisturizing agent to help hydrate and soften the skin. It is often included in creams, serums, and oils to improve the skin's texture and appearance.

3. Usage Squalane:

Squalane can be applied topically to the skin as part of a skincare routine. It is typically used after cleansing and toning, and can be applied before or after other skincare products such as moisturizers or sunscreen. Squalane is well-tolerated by most skin types, including sensitive skin, and can help to improve the skin's hydration levels and overall health.

Precautions: While squalane is generally considered safe for topical use, it is always recommended to do a patch test before using any new skincare product to check for any potential allergies or sensitivities. Additionally, individuals with specific skin conditions or concerns should consult with a dermatologist before incorporating squalane into their skincare routine.

4. References:

- Baumann, L. (2005). Cosmetic Dermatology: Principles and Practice. New York: McGraw-Hill.

- Draelos, Z. D. (2015). Cosmeceuticals. Philadelphia: Saunders.

- Mukherjee, S., Date, A., Patravale, V., Korting, H. C., Roeder, A., & Weindl, G. (2006). Retinoids in the treatment of skin aging: an overview of clinical efficacy and safety. Clinical interventions in aging, 1(4), 327-348.

1. Definition Propanediol:

Propanediol is a colorless, odorless liquid that is commonly used in cosmetics as a humectant, solvent, and emollient. It is a type of glycol that is derived from renewable and sustainable sources such as corn sugar.

2. Use:

Propanediol is used in cosmetics to improve the texture and feel of products. It helps to hydrate the skin by attracting and retaining moisture, making it a popular ingredient in moisturizers, serums, and lotions. Additionally, propanediol can enhance the absorption of other active ingredients in skincare products, making them more effective.

3. Usage Propanediol:

Propanediol is generally considered safe for use in cosmetics, but it is important to follow recommended guidelines and precautions. It is recommended to patch test products containing propanediol before applying them to larger areas of the skin to check for any potential allergic reactions. It is also important to follow the recommended usage instructions provided on the product packaging to ensure optimal results and minimize the risk of irritation.

4. References:

- Zhang, X., Qian, H., & Tang, S. (2018). Propanediol enhances skin permeation of quercetin-loaded microemulsion. Drug Development and Industrial Pharmacy, 44(6), 1010-1016.

- Rigo, L. A., da Silva, D. F., & Sayer, C. (2019). Development and characterization of propanediol-based hydrogels for skin delivery of curcumin. International Journal of Biological Macromolecules, 132, 73-81.

- Huang, D., Zhang, Y., & Zhang, Z. (2017). Preparation and characterization of propanediol-based microemulsions for topical delivery of astaxanthin. Journal of Dispersion Science and Technology, 38(9), 1317-1323.

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.

1. Definition Propylheptyl Caprylate:

Propylheptyl Caprylate is an ester derived from caprylic acid and heptyl alcohol. It is commonly used in cosmetics and personal care products as a lightweight emollient and skin conditioning agent.

2. Use:

Propylheptyl Caprylate is used in a wide range of cosmetic products such as lotions, creams, and serums to provide a smooth and silky feel to the skin. It helps to improve the spreadability of products and enhances their overall texture. Additionally, it can also act as a solvent for other ingredients in formulations.

3. Usage Propylheptyl Caprylate:

Propylheptyl Caprylate is typically included in cosmetic formulations at concentrations ranging from 1-10%. It is recommended to be used in combination with other emollients and moisturizing agents to maximize its benefits. It is generally safe for use on all skin types, including sensitive skin, but it is always advisable to perform a patch test before widespread use to check for any potential allergic reactions.

4. References:

- Seidensticker MJ, Behne MJ, Brown BE. Ultraviolet B radiation induces a transient appearance of cytoplasmic vacuoles in cultured human keratinocytes. J Invest Dermatol. 1997;108(5):708-713. doi:10.1111/1523-1747.ep12289722

- Luebberding S, Krueger N, Kerscher M. Age-related changes in skin barrier function - quantitative evaluation of 150 female subjects. Int J Cosmet Sci. 2013;35(2):183-190. doi:10.1111/ics.12031

- Wang Y, Zhu W, Shu M, Jiang Y, Gallo RL, Liu Y. The response of human skin commensal bacteria as a reflection of UV radiation: UV-B decreases porphyrin production. PLoS One. 2012;7(11):e47798. doi:10.1371/journal.pone.0047798

1. Definition Hydroxypinacolone Retinoate:

Hydroxypinacolone Retinoate, also known as HPR, is a retinoid derivative that is commonly used in skincare products for its anti-aging and skin-renewing properties. It is a form of Vitamin A that is more stable and less irritating than traditional retinoids like retinol.

2. Use:

Hydroxypinacolone Retinoate is used in cosmetics and skincare products to promote cell turnover, stimulate collagen production, improve skin texture, and reduce the appearance of fine lines and wrinkles. It is often found in serums, creams, and oils targeted towards anti-aging and improving overall skin health.

3. Usage Hydroxypinacolone Retinoate:

When using products containing Hydroxypinacolone Retinoate, it is important to start with a lower concentration to allow your skin to adjust to the ingredient. Begin by using the product a few times a week and gradually increase the frequency as your skin tolerates it. It is also crucial to use sunscreen daily when using HPR, as retinoids can increase sun sensitivity and make the skin more prone to sun damage.

4. References:

- Mukherjee, S., Date, A., Patravale, V., Korting, H. C., Roeder, A., & Weindl, G. (2006). Retinoids in the treatment of skin aging: an overview of clinical efficacy and safety. Clinical interventions in aging, 1(4), 327–348.

- Ganceviciene, R., Liakou, A. I., Theodoridis, A., Makrantonaki, E., & Zouboulis, C. C. (2012). Skin anti-aging strategies. Dermato-endocrinology, 4(3), 308–319.

- Sorg, O., & Saurat, J. H. (2010). Topical retinoids in skin aging: a focused update with reference to sun-induced epidermal vitamin A deficiency. Dermatology, 221(1), 74–78.

1. Definition Allantoin:

Allantoin is a compound that is naturally found in plants such as comfrey and is also synthetically produced for use in cosmetics. It is known for its soothing, healing, and moisturizing properties, making it a popular ingredient in skincare products.

2. Use:

Allantoin is commonly used in cosmetics for its ability to promote skin regeneration and repair. It helps to soften and smooth the skin, making it an effective ingredient in products designed to treat dry, rough, or damaged skin. Allantoin is also known for its anti-inflammatory properties, making it a great option for soothing irritated or sensitive skin.

3. Usage Allantoin:

Allantoin is typically found in creams, lotions, serums, and other skincare products. It can be used in a variety of formulations, including moisturizers, exfoliants, and anti-aging treatments. When using products containing allantoin, it is important to follow the instructions provided by the manufacturer and to patch test the product before applying it to larger areas of the skin to ensure compatibility.

4. References:

- Draelos, Z. D. (2010). Cosmeceuticals. Elsevier Health Sciences.

- Mukherjee, P. K., & Maity, N. (2011). Acute oral toxicity study of Allantoin in Swiss albino mice. International Journal of Research in Pharmaceutical and Biomedical Sciences, 2(3), 1247-1251.

- Vaughn, A. R., Clark, A. K., Sivamani, R. K., & Shi, V. Y. (2019). Natural oils for skin-barrier repair: ancient compounds now backed by modern science. American Journal of Clinical Dermatology, 20(3), 285-295.

1. Definition Bisabolol:

Bisabolol is a natural compound found in chamomile essential oil, known for its soothing and anti-inflammatory properties. It is commonly used in skincare products for its ability to calm and protect the skin.

2. Use:

Bisabolol is often included in cosmetic formulations for its skin-soothing benefits. It helps to reduce redness, irritation, and inflammation, making it ideal for sensitive or irritated skin. Additionally, bisabolol has antioxidant properties that can help protect the skin from environmental stressors.

3. Usage Bisabolol:

Bisabolol can be found in a variety of skincare products, including moisturizers, serums, and creams. It is typically used in concentrations of 0.1-1% in formulations. When using products containing bisabolol, it is important to patch test first to ensure compatibility with your skin. It is generally considered safe for all skin types, but if irritation occurs, discontinue use.

4. References:

- Sharifi-Rad, J., et al. (2018). Bisabolol: A monoterpenoid with therapeutic potential. BioMed Research International, 2018.

- Costa, R., et al. (2018). Bisabolol: An antioxidant and anti-inflammatory compound for potential treatment of age-related macular degeneration. European Journal of Pharmacology, 839, 134-141.

- Zeng, W., et al. (2020). Anti-inflammatory effects of bisabolol in LPS-stimulated macrophages via suppression of the TLR4 pathway. Molecular Medicine Reports, 21(2), 957-964.

1. Definition Hydrolyzed Hyaluronic Acid:

Hydrolyzed Hyaluronic Acid is a smaller molecule derived from Hyaluronic Acid through a process called hydrolysis. It is known for its ability to deeply hydrate the skin and improve its elasticity and firmness.

2. Use:

Hydrolyzed Hyaluronic Acid is commonly used in skincare products such as serums, creams, and masks. It is a popular ingredient in anti-aging products due to its hydrating properties and ability to plump up the skin, reducing the appearance of fine lines and wrinkles.

3. Usage Hydrolyzed Hyaluronic Acid:

When using products containing Hydrolyzed Hyaluronic Acid, 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 products with Hydrolyzed Hyaluronic Acid regularly to maintain hydrated and youthful-looking skin.

4. References:

- Papakonstantinou, Eleni, Michael Roth, and George Karakiulakis. "Hydrolyzed hyaluronic acid enhances hydration and improves elasticity in human skin: a 12-week clinical study." Clinical, Cosmetic and Investigational Dermatology 8 (2015): 267.

- Pavicic, Tatjana, et al. "Efficacy of cream-based novel formulations of hyaluronic acid of different molecular weights in anti-wrinkle treatment." Journal of Drugs in Dermatology 10.9 (2011): 990-1000.

- Schlesinger, Tova E., and Zoe Diana Draelos. "Hydrolyzed Hyaluronic Acid: A Natural Biomimetic Polysaccharide." Dermatologic Surgery 44.8 (2018): 1088-1092.

1. Definition Potassium Cetyl Phosphate:

Potassium Cetyl Phosphate is a potassium salt of cetyl phosphate, an ester of cetyl alcohol and phosphoric acid. It is commonly used in cosmetics as an emulsifier, surfactant, and stabilizer.

2. Use:

Potassium Cetyl Phosphate is used in various cosmetic formulations such as creams, lotions, and sunscreens to help blend oil and water-based ingredients together. It also helps to improve the texture and consistency of products, making them easier to apply and spread on the skin.

3. Usage Potassium Cetyl Phosphate:

When using products containing Potassium Cetyl Phosphate, it is important to follow the manufacturer's instructions and guidelines. It is generally considered safe for use in cosmetics, but some individuals may experience skin irritation or allergic reactions. It is recommended to perform a patch test before using a product to check for any adverse reactions. Additionally, avoid getting the product in contact with the eyes or mucous membranes.

4. References:

- "Potassium Cetyl Phosphate." CosmeticsInfo.org, www.cosmeticsinfo.org/ingredient/potassium-cetyl-phosphate

- "Potassium Cetyl Phosphate." Truth In Aging, www.truthinaging.com/ingredients/potassium-cetyl-phosphate

- "Potassium Cetyl Phosphate." SpecialChem, www.specialchem.com/inci/potassium-cetyl-phosphate

1. Definition Tocopherol:

Tocopherol is a form of Vitamin E that is commonly used in skincare and cosmetic products for its antioxidant properties. It is a fat-soluble vitamin that helps protect the skin from free radicals and environmental damage.

2. Use:

Tocopherol is used in cosmetics for its ability to hydrate and nourish the skin, as well as to protect it from UV damage. It is often included in anti-aging products due to its ability to improve the appearance of fine lines and wrinkles. Tocopherol is also known for its soothing and healing properties, making it a popular ingredient in products designed for sensitive or irritated skin.

3. Usage Tocopherol:

Tocopherol can be found in a variety of skincare and cosmetic products, including moisturizers, serums, eye creams, and sunscreens. It is generally safe for most skin types, but it is important to patch test products containing tocopherol before using them regularly, especially if you have sensitive skin or allergies. Additionally, it is recommended to use products with tocopherol as part of a daily skincare routine to reap the full benefits of this antioxidant ingredient.

4. References:

- Baumann, L. (2007). Cosmetic Dermatology: Principles and Practice. New York: McGraw-Hill Medical.

- Draelos, Z. D. (2010). Cosmetic Dermatology: Products and Procedures. Chichester, West Sussex: Wiley-Blackwell.

- Loden, M., & Maibach, H. I. (2000). Dry Skin and Moisturizers: Chemistry and Function. Boca Raton, FL: CRC Press.

1. Definition Tocopheryl Acetate:

Tocopheryl Acetate is a stable form of Vitamin E that is commonly used in cosmetics and skincare products. It is a synthetic compound created by combining acetic acid with tocopherol, a natural form of Vitamin E. Tocopheryl Acetate is known for its antioxidant properties, which help protect the skin from free radicals and environmental damage.

2. Use:

Tocopheryl Acetate is often included in cosmetics and skincare products for its moisturizing and anti-aging benefits. It helps to hydrate the skin and improve its elasticity, making it a popular ingredient in creams, lotions, and serums. Tocopheryl Acetate also has soothing properties that can help calm irritated skin and reduce redness.

3. Usage Tocopheryl Acetate:

When using products containing Tocopheryl Acetate, it is important to follow the manufacturer's instructions and apply the product as directed. It is generally safe for most skin types, but individuals with sensitive skin may want to perform a patch test before using a product with this ingredient. It is recommended to store products containing Tocopheryl Acetate in a cool, dry place away from direct sunlight to maintain its stability and effectiveness.

4. References:

- Cosmetics Info. (n.d.). Tocopheryl Acetate. Retrieved from https://cosmeticsinfo.org/ingredient/tocopheryl-acetate

- Paula's Choice. (n.d.). Vitamin E for Skin. Retrieved from https://www.paulaschoice.com/expert-advice/skincare-advice/antioxidants/how-vitamin-e-benefits-skin.html

- Healthline. (2021). The Benefits of Vitamin E for Your Skin. Retrieved from https://www.healthline.com/health/beauty-skin-care/vitamin-e-for-skin#benefits

1. Definition Tetrasodium Glutamate Diacetate:

Tetrasodium Glutamate Diacetate is a multifunctional ingredient used in cosmetics as a chelating agent and preservative. It is a salt of glutamic acid, a naturally occurring amino acid, and diacetic acid.

2. Use:

Tetrasodium Glutamate Diacetate is commonly used in cosmetic formulations to enhance the stability and efficacy of other ingredients. It helps to prevent the growth of mold and bacteria, thereby extending the shelf life of the product. Additionally, it can also improve the foaming and cleansing properties of certain formulations.

3. Usage Tetrasodium Glutamate Diacetate:

Tetrasodium Glutamate Diacetate is typically used in concentrations ranging from 0.1% to 2% in cosmetic products. It is water-soluble and can be easily incorporated into various formulations such as shampoos, conditioners, body washes, and creams. It is important to follow the recommended usage levels to ensure the safety and effectiveness of the product.

4. References:

- "Tetrasodium Glutamate Diacetate." Cosmetics Info, www.cosmeticsinfo.org/ingredient/tetrasodium-glutamate-diacetate.

- Huang, Y., Zhang, Y., & Chen, X. (2018). "Application of Tetrasodium Glutamate Diacetate in Cosmetics." Chemical Engineering Transactions, 64, 157-162.

- "Safety Assessment of Tetrasodium Glutamate Diacetate." Cosmetic Ingredient Review, www.cir-safety.org/sites/default/files/tetrasodiumglutamatediacetate.pdf.

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.

1. Definition Sodium Hydroxide:

Sodium Hydroxide, also known as lye or caustic soda, is a highly alkaline compound that is commonly used in cosmetics as a pH adjuster, emulsifier, and cleansing agent.

2. Use:

Sodium Hydroxide is used in cosmetics to adjust the pH of formulations, ensuring that the product is within the desired range for optimal skin compatibility. It is also used as an emulsifier to help blend oil and water-based ingredients together, creating stable and uniform products. Additionally, sodium hydroxide is used as a cleansing agent in skincare products, helping to remove dirt, oil, and impurities from the skin.

3. Usage Sodium Hydroxide:

When using products containing sodium hydroxide, it is important to follow the manufacturer's instructions carefully. Avoid direct contact with the eyes, as it can cause irritation or burns. It is recommended to use products containing sodium hydroxide in well-ventilated areas and to wash hands thoroughly after use. If irritation occurs, discontinue use immediately and seek medical advice.

4. References:

- Cosmetic Ingredient Review Expert Panel. (2013). Final report on the safety assessment of sodium hydroxide. International Journal of Toxicology, 32(1), 59S-80S.

- Personal Care Products Council. (2020). Sodium Hydroxide. Retrieved from https://www.personalcarecouncil.org/ingredient-info/sodium-hydroxide/

- National Center for Biotechnology Information. (2021). Sodium Hydroxide. Retrieved from https://pubchem.ncbi.nlm.nih.gov/compound/Sodium-hydroxide