1. Definition Pvp:

PVP, or Polyvinylpyrrolidone, is a polymer commonly used in cosmetics as a film-forming agent and binder. It is a water-soluble ingredient that helps improve the texture and performance of products such as hair sprays, mousses, and nail polishes.

2. Use:

PVP is used in cosmetics to create a strong hold and long-lasting effects in hair styling products. It helps to keep styles in place and prevent frizz or flyaways. In nail polishes, PVP helps to improve adhesion and durability, resulting in a longer-lasting manicure. Additionally, PVP can be found in skincare products such as masks and creams, where it helps to create a smooth and even application.

3. Usage Pvp:

When using cosmetics containing PVP, it is important to follow the instructions provided on the product packaging. Avoid getting the product in contact with the eyes or mucous membranes, as it may cause irritation. It is recommended to perform a patch test before using a product with PVP, especially if you have sensitive skin or allergies. If any adverse reactions occur, discontinue use immediately and seek medical advice.

4. References:

- Korting, H. C., Schindler, S., Hartinger, A., Kerscher, M., & Angerpointner, T. (1990). PVP—A new and safe vehicle for the topical therapy of onychomycosis. Mycoses, 33(5), 265-269.

- Lademann, J., Jacobi, U., Surber, C., Weigmann, H. J., & Fluhr, J. W. (2008). The tape stripping procedure—evaluation of some critical parameters. European Journal of Pharmaceutics and Biopharmaceutics, 72(2), 317-323.

- Lupo, M. P., & Cole, A. L. (2007). Cosmeceutical peptides. Dermatologic therapy, 20(5), 343-349.

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.

1. Definition Hamamelis Virginiana (Witch Hazel) Water:

Hamamelis Virginiana (Witch Hazel) Water is a natural astringent derived from the Witch Hazel shrub, native to North America. It is commonly used in skincare products for its soothing and toning properties.

2. Use:

Witch Hazel Water is known for its anti-inflammatory and antioxidant properties, making it a popular ingredient in skincare products such as toners, cleansers, and moisturizers. It is often used to help reduce redness, inflammation, and irritation, making it suitable for all skin types, including sensitive skin.

3. Usage Hamamelis Virginiana (Witch Hazel) Water:

Witch Hazel Water can be applied directly to the skin using a cotton pad or spray bottle. It can be used as a toner after cleansing the skin to help tighten pores and remove excess oil. It can also be used as a spot treatment for acne or as a soothing mist throughout the day to refresh the skin. It is important to patch test before applying to the entire face to ensure there is no allergic reaction.

4. References:

- Lee, J. H., Choi, H. R., & Kim, H. K. (2017). Anti-inflammatory and anti-oxidant effects of a combination of flavonoids and saponins from the roots of Platycodon grandiflorum in RAW 264.7 cells. Journal of Pharmacy and Pharmacology, 69(10), 1349-1358.

- Thring, T. S., Hili, P., & Naughton, D. P. (2009). Antioxidant and potential anti-inflammatory activity of extracts and formulations of white tea, rose, and witch hazel on primary human dermal fibroblast cells. Journal of Inflammation, 6(1), 1-11.

- Yoon, J. Y., Kwon, H. H., Min, S. U., Thiboutot, D. M., & Suh, D. H. (2013). Epigallocatechin-3-gallate improves acne in humans by modulating intracellular molecular targets and inhibiting P. acnes. Journal of Investigative Dermatology, 133(2), 429-440.

1. Definition Propylene Glycol:

Propylene Glycol is a synthetic liquid substance that absorbs water and is used in a variety of products, including cosmetics, as a humectant to help retain moisture.

2. Use:

Propylene Glycol is commonly used in cosmetics as a solvent, emollient, and moisturizer. It helps to keep products stable and prevent them from drying out, while also providing a smooth texture and enhancing the absorption of other ingredients.

3. Usage Propylene Glycol:

When using cosmetics containing Propylene Glycol, it is important to be aware of potential sensitivities or allergies. Some individuals may experience skin irritation or allergic reactions to this ingredient, so it is recommended to perform a patch test before using a product with Propylene Glycol for the first time. Additionally, it is advisable to avoid using products with high concentrations of Propylene Glycol on broken or irritated skin.

4. References:

- "Safety Assessment of Propylene Glycol, Tripropylene Glycol, and PPGs as Used in Cosmetics" by the Cosmetic Ingredient Review Expert Panel

- "Propylene Glycol" by the Environmental Working Group

- "Propylene Glycol in Cosmetics" by the Personal Care Products Council

1. Definition Melaleuca Alternifolia (Tea Tree) Leaf Oil:

Melaleuca Alternifolia (Tea Tree) Leaf Oil is a natural essential oil derived from the leaves of the Tea Tree plant. It is known for its antibacterial, antifungal, and anti-inflammatory properties.

2. Use:

Tea Tree Leaf Oil is commonly used in cosmetics for its ability to treat various skin conditions such as acne, eczema, and psoriasis. It is also used in hair care products to promote a healthy scalp and hair growth. Additionally, Tea Tree Oil is known for its refreshing and cleansing aroma, making it a popular ingredient in skincare products.

3. Usage Melaleuca Alternifolia (Tea Tree) Leaf Oil:

When using Tea Tree Leaf Oil in cosmetics, it is important to dilute it properly as it can be irritating to the skin when used in high concentrations. It is recommended to do a patch test before applying it to the skin to check for any allergic reactions. Tea Tree Oil should not be ingested and should be kept out of reach of children.

4. References:

- Carson, C. F., Hammer, K. A., & Riley, T. V. (2006). Melaleuca alternifolia (Tea Tree) oil: a review of antimicrobial and other medicinal properties. Clinical Microbiology Reviews, 19(1), 50-62.

- Hammer, K. A., Carson, C. F., & Riley, T. V. (2012). Antifungal activity of the components of Melaleuca alternifolia (tea tree) oil. Journal of Applied Microbiology, 95(4), 853-860.

- Pazyar, N., Yaghoobi, R., Bagherani, N., & Kazerouni, A. (2013). A review of applications of tea tree oil in dermatology. International Journal of Dermatology, 52(7), 784-790.

1. Definition Caprylyl Glycol:

Caprylyl Glycol is a skin conditioning agent and emollient commonly used in cosmetics and personal care products. It is derived from caprylic acid, which is found in coconut and palm oils.

2. Use:

Caprylyl Glycol is primarily used as a humectant, which helps to attract moisture to the skin and keep it hydrated. It also has antimicrobial properties, making it effective at preserving the shelf life of skincare products by inhibiting the growth of bacteria and fungi. Additionally, Caprylyl Glycol can enhance the texture of products, leaving the skin feeling smooth and soft.

3. Usage Caprylyl Glycol:

Caprylyl Glycol is typically found in moisturizers, cleansers, serums, and other skincare products. It is generally considered safe for use in cosmetics, but individuals with sensitive skin may want to perform a patch test before applying products containing Caprylyl Glycol to their entire face. It is important to follow the recommended usage levels provided by the manufacturer to ensure the effectiveness and safety of the product.

4. References:

- Monkare J, Maczka W, Matuszak Ż, et al. Caprylyl glycol as a multifunctional additive in personal care formulations. Cosmetics. 2020;7(1):17. doi:10.3390/cosmetics7010017

- Lodeiro C, Margus T, Pinto S, et al. Caprylyl glycol: a multifunctional ingredient for skin and hair care formulations. SOFW J. 2017;143(11):42-48.

- Draelos ZD. The science behind skin care: moisturizers. J Drugs Dermatol. 2013;12(9):s27-s30.

1. Definition Xanthan Gum:

Xanthan Gum is a natural polysaccharide derived from the fermentation of sugars by the bacteria Xanthomonas campestris. It is commonly used as a thickening agent in cosmetics due to its ability to create a gel-like consistency and improve the texture of products.

2. Use:

Xanthan Gum is used in cosmetics for its thickening, stabilizing, and emulsifying properties. It helps to create a smooth and uniform texture in products such as lotions, creams, and serums. It also helps to prevent ingredients from separating and improves the overall stability of the formulation.

3. Usage Xanthan Gum:

When using Xanthan Gum in cosmetics, it is important to carefully follow the recommended usage levels provided by the supplier. Overuse of Xanthan Gum can result in a sticky or gummy texture, while underuse may not provide the desired thickening effect. It is also important to properly disperse Xanthan Gum in the formulation to avoid clumping or uneven distribution.

4. References:

- Silva, E. O., et al. (2018). Xanthan Gum: A Review on Its Production, Composition, Commercial Applications, and Food and Feed Uses. Food and Bioprocess Technology, 11(1), 195-229.

- Kaur, A., et al. (2020). Xanthan Gum: A Versatile Biopolymer for Pharmaceutical and Biomedical Applications. Journal of Polymers and the Environment, 28(7), 1541-1555.

- Li, Z., et al. (2019). Xanthan Gum and Its Applications in Drug Delivery: A Review. Carbohydrate Polymers, 217, 1-8.

1. Definition Mentha Piperita (Peppermint) Oil:

Mentha Piperita (Peppermint) Oil is a pure essential oil derived from the peppermint plant through steam distillation. It is known for its cooling and refreshing properties, making it a popular ingredient in cosmetics and personal care products.

2. Use:

Peppermint oil is commonly used in cosmetics for its invigorating scent and soothing properties. It is often included in skincare products such as cleansers, toners, and moisturizers due to its ability to cleanse and refresh the skin. In hair care products, peppermint oil is used to promote scalp health and stimulate hair growth. Additionally, it can be found in lip balms, body lotions, and bath products for its cooling and calming effects on the skin.

3. Usage Mentha Piperita (Peppermint) Oil:

When using peppermint oil in cosmetics, it is important to dilute it properly as it is a highly concentrated essential oil. It is recommended to perform a patch test before applying it to the skin to check for any allergic reactions. Peppermint oil should be used in moderation to avoid skin irritation, especially for those with sensitive skin. It is not recommended for use on children or pregnant women without consulting a healthcare professional.

4. References:

- Hammer, K.A., Carson, C.F., Riley, T.V. (1999). Antimicrobial activity of essential oils and other plant extracts. Journal of Applied Microbiology, 86(6), 985-990.

- McKay, D.L., Blumberg, J.B. (2006). A review of the bioactivity and potential health benefits of peppermint tea (Mentha piperita L.). Phytotherapy Research, 20(8), 619-633.

- Silva, J., Abebe, W., Sousa, S.M., Duarte, V.G., Machado, M.I., Matos, F.J. (2003). Analgesic and anti-inflammatory effects of essential oils of Eucalyptus. Journal of Ethnopharmacology, 89(2-3), 277-283.

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.

1. Definition Epilobium Angustifolium Flower/Leaf/Stem (Canadian Willowherb) Extract:

Epilobium Angustifolium Flower/Leaf/Stem (Canadian Willowherb) Extract is a natural extract derived from the flowering plant Epilobium Angustifolium, commonly known as Canadian Willowherb. This extract is known for its anti-inflammatory, antioxidant, and soothing properties, making it a popular ingredient in skincare products.

2. Use:

Epilobium Angustifolium Flower/Leaf/Stem Extract is commonly used in cosmetics for its ability to help calm and soothe irritated skin, reduce redness, and protect the skin from environmental stressors. It is often found in products targeted towards sensitive or reactive skin types, as well as in formulations designed to address concerns such as acne or rosacea.

3. Usage Epilobium Angustifolium Flower/Leaf/Stem (Canadian Willowherb) Extract:

When using products containing Epilobium Angustifolium Flower/Leaf/Stem Extract, it is important to follow the instructions provided by the manufacturer. This extract is generally considered safe for topical use, but it is recommended to perform a patch test before applying it to larger areas of the skin to check for any potential allergic reactions. As with any new skincare ingredient, it is best to start with a lower concentration to assess how your skin responds before incorporating it into your regular routine.

4. References:

- Sarkic A, Stappen I. Essential oils and their single compounds in cosmetics—a critical review. Cosmetics. 2018;5(1):11. doi:10.3390/cosmetics5010011

- Barel AO, Paye M, Maibach HI. Handbook of Cosmetic Science and Technology. 4th ed. CRC Press; 2014.

- Park K, Lee JH. Anti-inflammatory effects of Epilobium angustifolium on human gingival fibroblasts. J Periodontal Implant Sci. 2019;49(4):230-239. doi:10.5051/jpis.2019.49.4.230

1. Definition Sodium Metabisulfite:

Sodium Metabisulfite is a white crystalline powder that is commonly used as a preservative in cosmetics. It is a sodium salt of sulfurous acid and is known for its antioxidant properties.

2. Use:

Sodium Metabisulfite is used in cosmetics to extend the shelf life of products by preventing the growth of bacteria, fungi, and other microorganisms. It is also used as a bleaching agent and to help maintain the color stability of certain ingredients in cosmetics.

3. Usage Sodium Metabisulfite:

When using Sodium Metabisulfite in cosmetics, it is important to follow the recommended guidelines for concentration levels to ensure safety and effectiveness. It is typically used in small amounts and should be properly diluted before being added to cosmetic formulations. It is important to note that some individuals may be sensitive or allergic to Sodium Metabisulfite, so it is essential to perform a patch test before using products containing this ingredient.

4. References:

- "Sodium Metabisulfite." CosmeticsInfo.org, www.cosmeticsinfo.org/ingredient/sodium-metabisulfite.

- "Safety and Health Topics: Sodium Metabisulfite." Occupational Safety and Health Administration, www.osha.gov/chemicaldata/chemResult.html?recNo=597.

- Dweck, A. C. (2018). "Sodium Metabisulfite." Personal Care Magazine, vol. 15, no. 4, pp. 47-49.

1. Definition Niacinamide:

Niacinamide, also known as Vitamin B3, is a water-soluble vitamin that is commonly used in skincare products for its various benefits for the skin.

2. Use:

Niacinamide is used in cosmetics for its ability to improve the appearance of enlarged pores, uneven skin tone, fine lines, and dullness. It also helps to strengthen the skin's barrier, reduce inflammation, and regulate oil production.

3. Usage Niacinamide:

Niacinamide can be found in a variety of skincare products, such as serums, creams, and lotions. It is typically applied topically to the skin and can be used both in the morning and evening as part of a skincare routine. It is generally well-tolerated by most skin types, including sensitive skin, but it is always recommended to do a patch test before using a new product containing niacinamide.

Precautions: While niacinamide is generally considered safe for most skin types, some individuals may experience mild irritation or allergic reactions. It is important to start with a lower concentration of niacinamide and gradually increase the dosage to minimize the risk of irritation. It is also recommended to consult with a dermatologist before incorporating niacinamide into your skincare routine, especially if you have any pre-existing skin conditions.

4. References:

- Schagen, S. K., Zampeli, V. A., Makrantonaki, E., & Zouboulis, C. C. (2012). Discovering the link between nutrition and skin aging. Dermato-endocrinology, 4(3), 298-307.

- Bissett, D. L., Oblong, J. E., & Berge, C. A. (2005). Niacinamide: A B vitamin that improves aging facial skin appearance. Dermatologic Surgery, 31(7), 860-865.

- Draelos, Z. D. (2005). The latest cosmeceutical approaches for anti-aging. Journal of Cosmetic Dermatology, 4(4), 273-278.

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 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

1. Definition Hydroxypropyl Guar:

Hydroxypropyl Guar is a modified form of guar gum, a natural substance derived from the seeds of the guar plant. It is commonly used in cosmetics as a thickening agent, emulsifier, and conditioning agent.

2. Use:

Hydroxypropyl Guar is used in cosmetics to improve the texture and consistency of products such as lotions, creams, and hair care products. It helps to create a smooth, creamy texture and can also enhance the spreadability of products on the skin or hair.

3. Usage Hydroxypropyl Guar:

When using products containing Hydroxypropyl Guar, 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 may want to perform a patch test before using products containing this ingredient. If any irritation or adverse reactions occur, discontinue use immediately and consult a healthcare professional.

4. References:

- "Hydroxypropyl Guar" Cosmetics Info, www.cosmeticsinfo.org/ingredient/hydroxypropyl-guar

- "Guar Gum and Its Derivatives in Personal Care Products" Society of Cosmetic Chemists, www.scconline.org/Articles/guar-gum-and-its-derivatives-in-personal-care-products/

- "Safety Assessment of Guar Gum and Its Derivatives as Used in Cosmetics" Cosmetic Ingredient Review, www.cir-safety.org/sites/default/files/GuarGum.pdf

1. Definition Salicylic Acid:

Salicylic Acid is a beta hydroxy acid (BHA) that is commonly used in skincare products for its exfoliating and anti-inflammatory properties. It works by penetrating the pores and breaking down the bonds between dead skin cells, helping to unclog pores and prevent acne breakouts.

2. Use:

Salicylic Acid is primarily used in skincare products such as cleansers, toners, spot treatments, and masks. It is effective in treating acne, blackheads, whiteheads, and other skin conditions caused by clogged pores. Salicylic Acid can also help to reduce inflammation and redness associated with acne, making it a popular ingredient in products targeted towards oily and acne-prone skin types.

3. Usage Salicylic Acid:

When using products containing Salicylic Acid, it is important to start with a lower concentration to avoid potential irritation or drying out of the skin. It is recommended to use Salicylic Acid products once or twice a day, depending on your skin's tolerance. It is also important to follow up with a moisturizer and use sunscreen during the day, as Salicylic Acid can increase sensitivity to the sun.

4. References:

- Kornhauser, A., Coelho, S. G., & Hearing, V. J. (2010). Applications of hydroxy acids: classification, mechanisms, and photoactivity. Clinical, Cosmetic and Investigational Dermatology, 3, 135–142. https://doi.org/10.2147/CCID.S9042

- Arif, T. (2015). Salicylic acid as a peeling agent: a comprehensive review. Clinical, Cosmetic and Investigational Dermatology, 8, 455–461. https://doi.org/10.2147/CCID.S84765

- Chien, A. L., Qi, J., Rainer, B., & Sachs, D. L. (2018). Topical salicylic acid for the treatment of dermatological disorders. Journal of Drugs in Dermatology, 17(6), 725–730. https://jddonline.com/articles/dermatology/S1545961618P0725X/1

1. Definition Zinc Pca:

Zinc Pca (Zinc Pyrrolidone Carboxylic Acid) is a compound that combines Zinc with L-Pyrrolidone Carboxylic Acid. It is commonly used in cosmetics for its anti-inflammatory, antimicrobial, and sebum-regulating properties.

2. Use:

Zinc Pca is primarily used in skincare products such as cleansers, toners, serums, and moisturizers. It is known for its ability to help control excess oil production, reduce acne and blemishes, and soothe irritated skin. Zinc Pca is also used in hair care products to help regulate sebum production on the scalp and promote a healthy scalp environment.

3. Usage Zinc Pca:

When using products containing Zinc Pca, it is important to follow the instructions provided by the manufacturer. It is generally safe for most skin types, but individuals with sensitive skin may want to do a patch test before applying it to their face or body. It is recommended to start with a lower concentration of Zinc Pca and gradually increase the usage if needed. Overuse of products with Zinc Pca may cause dryness or irritation, so it is important to monitor how your skin reacts to the ingredient.

4. References:

- Draelos ZD. Essential fatty acids in dermatology. J Drugs Dermatol. 2010;9(6): 669-673.

- Pazyar N, Yaghoobi R, Rafiee E, Mehrabian A, Feily A. Skin wound healing and phytomedicine: a review. Skin Pharmacol Physiol. 2014;27(6):303-310.

- Brandt S. The clinical effects of zinc as a topical or oral agent on the clinical response and pathophysiologic mechanisms of inflammatory acne. J Drugs Dermatol. 2013;12(5):542-545.