In the United States, the most commonly used treatment for hyperpigmentation is 1,4-benzenediol, which is known as hydroquinone. Methods and products for nucleic acid production and delivery, Nucleic acid product and its administration method, Nucleic acid product and method of administration thereof, Compositions and systems for the treatment of hyperpigmentation, Methods for prevention of post-inflammatory hyperpigmentation, Skin care compositions containing retinoids, Improved method for stability of ageing comprising thirosinase inhibitor activity, Use of ascorbic acid to reduce irritation of topically applied active ingredients, COSMETIC COMPOSITIONS WITH ANTIMICOTIC PROPERTIES, EFFECTIVE AGAINST PSORIASIS AND HAIR LOSS AND COSMETIC METHOD FOR, Treatment or prevention of undesired skin pigmentation, Skin care compositions and method of improving skin appearance, Ultrasound enhancement of percutaneous drug absorption, Skin whiteners containing hydroxytetronic acid, Stabilized retinoid-containing skin care compositions, Retinoid compositions containing a water soluble antioxidant and a chelator, Composition and method for treating rosacea and sensitive skin with free radical scavengers, Skin care compositions containing imidazoles and retinoids, Stable compositions containing a retinoid and an enzyme based antioxidant system, Self-tanning compositions containing dha and propolis extract, Composition and process for stabilizing oxygen-unstable species, Bleaching preparation and cosmetic for preventing and improving aging of skin, Composition and method for the treatment of pigmentation disorders, Composition for cosmetic or pharmaceutical use, Remedies for pigmentation and melanocyte proliferation inhibitors, Public reference made under article 153(3) epc to a published international application that has entered the european phase, Divisional application: reference to earlier application, Information on the status of an ep patent application or granted ep patent. A further embodiment of the invention includes a method for stabilizing a hydroquinone composition (with about 1% to about 12% hydroquinone, preferably about 2% to about 10%, more preferably about 2% to about 8%, and most preferably about 3% to about 4%) with a neutral pH of from about 5.5 to about 8.0, more preferably a pH of from about 5.5 to about 7.5, and most preferably at a pH of from about 6.0 to about 7.5, by adding a water-soluble antioxidant, preferably sulfite, including but not limited to sulfites, bisulfites, metabisulfites, their salts and their derivatives, most preferably sodium metabisulfite, and a cationic salt of acidic ascorbyl esters, preferably sodium ascorbyl phosphate, more preferably aminopropyl ascorbyl phosphate, most preferably magnesium ascorbyl phosphate. Using a laser-monitoring observation technique, the solubility of hydroquinone in water, methanol, ethanol, 2-propanol, ethyl acetate, butyl acetate, and acetic acid were measured at temperatures ranging from 276.65 K to 345.10 K under the atmospheric pressure. 0000002585 00000 n 374 0 obj << /Linearized 1 /O 376 /H [ 807 1414 ] /L 581425 /E 96582 /N 109 /T 573826 >> endobj xref 374 19 0000000016 00000 n . Our team has been notified and we will fix it as soon as possible. At 40C, 4% hydroquinone compositions are more likely to excessively discolor and magnesium ascorbyl phosphate helps to stabilize the color, by preventing the brownish black discoloration and maintaining an amber color. Correspondence to Van Haelst, P. Heesen, F. Van Der Wielen, H. Govers, Chemosphere 29, 16511660 (1994), Article Thus, merely adding one retinoid to a hydroquinone composition would result in instability and/or discoloration, and adding hydroquinone to a retinoid product would have a similar result. Please sign in to view account pricing and product availability. [19][20], In 2006, the United States Food and Drug Administration revoked its previous approval of hydroquinone and proposed a ban on all over-the-counter preparations. 43, 13111316 (2007), J. Qing-Zhu, M. Pei-Sheng, Z. Huan, X. Shu-Qian, W. Qiang, Q. Yan, Fluid Phase Equilib. Get medical attention. 0000000731 00000 n 2017-02-16T10:10:56+01:00 Calorim. The aquatic toxicity of hydroquinone to fresh water fish, Daphnia, and algae was between 0.050- . However, hydroquinone discolors at the pH range of 7.0 to 8.5. I can't use water because I cannot dissolve enough Hydroquinone into it to reach the desired concentration. The obtained results show that the solubility of benzoic acid in water is greater than that of salicylic acid, but in the case of the two isomers of dihydroxybenzene, the solubility of resorcinol is approximately 100 times that of hydroquinone. Belhachemi, B., Makhlouf, H. & Belhachemi, M.H. One of these, 4-butylresorcinol, has been proven to be more effective at treating melanin-related skin disorders by a wide margin, as well as safe enough to be made available over the counter. [31], Hydroquinones are one of the two primary reagents in the defensive glands of bombardier beetles, along with hydrogen peroxide (and perhaps other compounds, depending on the species), which collect in a reservoir. [24], Numerous studies have revealed that hydroquinone, if taken orally, can cause exogenous ochronosis, a disfiguring disease in which blue-black pigments are deposited onto the skin; however, skin preparations containing the ingredient are administered topically. Lastly, I'd like to add benzoic acid for preservation purposes. On this Wikipedia the language links are at the top of the page across from the article title. 0000085850 00000 n D7VJV//KZ&t}JSW/L@,l@^ D@ @8 i W `^;V rD}25p>.Bv1}\_E p9 endstream endobj 392 0 obj 1303 endobj 376 0 obj << /Type /Page /Parent 350 0 R /Resources 377 0 R /Contents 381 0 R /MediaBox [ 0 0 595 842 ] /CropBox [ 0 0 595 842 ] /Rotate 0 >> endobj 377 0 obj << /ProcSet [ /PDF /Text ] /Font << /TT2 379 0 R /TT4 383 0 R /TT6 385 0 R >> /ExtGState << /GS1 387 0 R >> /ColorSpace << /Cs6 378 0 R >> >> endobj 378 0 obj [ /ICCBased 386 0 R ] endobj 379 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 252 /Widths [ 250 0 408 500 0 833 778 180 333 333 500 564 250 333 250 278 500 500 500 500 500 500 500 500 500 500 278 278 564 564 564 444 921 722 667 667 722 611 556 722 722 333 389 722 611 889 722 722 556 722 667 556 611 722 722 944 722 722 611 333 0 333 0 500 0 444 500 444 500 444 333 500 500 278 278 500 278 778 500 500 500 500 333 389 278 500 500 722 500 500 444 0 0 0 541 0 0 0 0 0 0 0 500 0 0 0 0 0 0 0 0 0 0 0 333 0 0 0 500 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 400 0 0 0 0 576 0 0 0 0 0 0 0 750 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 722 0 0 0 0 0 722 0 0 500 444 0 0 0 444 0 0 0 444 444 0 0 0 0 0 0 0 0 0 0 500 0 500 0 0 0 0 0 500 ] /Encoding /WinAnsiEncoding /BaseFont /BCGIOE+TimesNewRoman /FontDescriptor 380 0 R >> endobj 380 0 obj << /Type /FontDescriptor /Ascent 891 /CapHeight 656 /Descent -216 /Flags 34 /FontBBox [ -568 -307 2028 1007 ] /FontName /BCGIOE+TimesNewRoman /ItalicAngle 0 /StemV 94 /XHeight 0 /FontFile2 388 0 R >> endobj 381 0 obj << /Length 462 /Filter /FlateDecode >> stream In 1-octanol, the decreasing order of the solubility of these compounds is as follows: resorcinol>benzoic acid>salicylic acid>hydroquinone. . Inhalation Remove to fresh air. 552591, Z. Esina, M. Korchuganova, Theor. uv curable cellulose estersuv curable cellulose esters . . An improvement in the color stability of the 4% hydroquinone compositions is seen at and above 2.0% magnesium ascorbyl phosphate in the 6-7 pH range. 57, 295300 (2013), R. F. Pires, M. R. Franco Jr, Fluid Phase Equilib. Cationic salts of acidic ascorbyl esters, including inorganic salts, preferably magnesium ascorbyl phosphate, and amino acyl derivatives, preferably aminopropyl ascorbyl phosphate, are preferred in this invention. Then take the water and put the measurement into the microwave until boiled. By accepting all cookies, you agree to our use of cookies to deliver and maintain our services and site, improve the quality of Reddit, personalize Reddit content and advertising, and measure the effectiveness of advertising. Hydroquinone[1] Idrochinone Quinol 1,4-Dihydroxybenzene p-dihydroxybenzene p-hydroxyphenol 1,4-Hydroxy benzene Identifiers CAS Number 123-31-9 Y 3D model (JSmol) Interactive image Beilstein Reference 605970 ChEBI CHEBI:17594 Y ChEMBL ChEMBL537 Y ChemSpider 764 Y DrugBank DB09526 ECHA InfoCard 100.004.199 EC Number 204-617-8 Gmelin Reference 2742 Classical photo shops also sell hydroquinone. endstream endobj 277 0 obj <>stream You take the cream, put it in a container, take the powder measurement and add it. Data 51, 16681671 (2006), C. L. Yaws, S.-C. Lin, Enthalpy of fusion at freezing pointOrganic compounds, in Thermophysical Properties of Chemicals and Hydrocarbons, William Andrew Publishing (Elsevier, 2009), pp. 65, 5786 (1998), Y.-H. Zhang, Trends Analyt. Additionally, a water-soluble antioxidant, preferably a sulfite, including but not limited to sulfites, bisulfites, metabisulfites, their salts and their derivatives, most preferably sodium metabisulfite, may be helpful in stabilizing the hydroquinone composition. With an account you can check out faster, view your online order history and access your shopping bag or saved items from any device. HlRMo0WB:NnVCnE4(i0 (1* )@NzHR!>i;8XaXnsO0LNT0l$B%"NAb0I9V *6/-\vn0W"fKF:AAgl:psRZ?k`&eB IUQ0ET;W#vL=@XwRG{-LHlTz]^s%OB(GF 11'I isosorbide, Ascorbic acid, i.e. I've been presented with the problem of trying to dissolve Hydroquinone in a solvent other than water. Eng. Data 53, 12781282 (2008), A. [21][25][23] NTP evaluation showed some evidence of long-term carcinogenic and genotoxic effects[26], While hydroquinone remains widely prescribed for treatment of hyperpigmentation, questions raised about its safety profile by regulatory agencies in the EU, Japan, and USA encourage the search for other agents with comparable efficacy. Without being limited to the mechanism of this discoloration, it is believed that the discoloration may be caused at least in part by oxidation of the hydroquinone. International Journal of Thermophysics Consistent with a condensation reaction, water was determined to be the primary byproduct. Google Scholar, W. J. Weber Jr, Y.-P. Chin, C. P. Rice, Water Res. Res. The Beaver: Its Life and Impact. 15, 188196 (1996), U. Domaska, Fluid Phase Equilib. This invention relates to methods and compositions for the treatment of pigmentation disorders, including hyperpigmentation and vitiligo. Therefore, the solubility values of hydroquinone in different solvents are required; however, the data availability in the literature is poor.3-7 In this work, the solubility data of hydroquinone in water, methanol, ethanol, 2-propanol, ethyl acetate, butyl acetate, and acetic acid from 276.65 K to 345.10 K under atmospheric pressure were . Toxicol. If you have any specific questions, please include them in the comments section. Continue rinsing.IF SWALLOWED: Call a POISON CENTER or doctor/physician if you feel unwell.Avoid release to the environment.WARNING: The information provided on this web site was developed in compliance with European Union (EU) regulations and is correct to the best of our knowledge, information and belief at the date of its publication. Exceptional antioxidant qualities are seen at 0.10% (all percentages in the application are weight percent) and above, preferably from about 0.05% to about 0.5% for sodium metabisulfite. C6H4O2) is formed. 0000005089 00000 n 0.6. glycerin, 2.5. Stir until uniform. Protected retinoid may be added to these compositions for additional skin benefit effects. I can only tell you how to mix the powder solution to the liquid solvent. The natural pH for conventional hydroquinone compositions is acidic, generally less than about 4 even though this is harsh to the skin and to other components of the product. 0000002379 00000 n 0000004433 00000 n 322, 4855 (2012), K. Tamura, T. Kasuga, T. Nakagawa, Fluid Phase Equilib. Hydroquinone (C 6 H 4 (OH) 2), also known as benzene-1,4-diol or quinol, is an aromatic organic compound, with a variety of uses in chemistry. It is moderately soluble in water and highly soluble in alcohol. Other solubilities: soluble in alcohol and ether,slightly soluble in benzene,readily soluble in ethanol,acetone and methanol, Needle-like Crystals or Crystalline Powder. A3, Free format text: We have discovered that a hydroquinone composition (with about 1 to about 12% hydroquinone, preferably with about 2% to about 10%, more preferably with about 2% to about 8%, more preferably with about 2% to about 4%, most preferably with about 3% to about 4% hydroquinone) with preferably a pH of from about 5.5 to about 8.0, more preferably a pH of from about 5.5 to about 7.5, and most preferably at a pH of from about 6.0 to about 7.5, can include cationic salts of acidic ascorbyl esters, preferably sodium ascorbyl phosphate, more preferably aminopropyl ascorbyl phosphate, most preferably magnesium ascorbyl phosphate as an antioxidant and the color destabilization problems are appreciably less as compared to hydroquinone compositions without such a cationic salt of acidic ascorbyl esters in the neutral pH range: preferably a pH of from about 5.5 to about 8.0, more preferably a pH of from about 5.5 to about 7.5, and most preferably at a pH of from about 6.0 to about 7.5. However, the oil-soluble TBHQ is more hydrophobic with a distinctly increased log P value compared to HQ. Discoloration of hydroquinone compositions may be accelerated by repeated exposure to oxygen or exposing the compositions to high temperatures, which may be found inside a car or delivery vehicle on a hot sunny day. Tests, which results are detailed in the following two tables, are performed at 5C and 40C for certain percentages of magnesium ascorbyl phosphate at specific pHs. This study was funded by Ministre de l'Enseignement Suprieur et de la Recherche Scientifique. Some products also contain sunscreens. Other properties of hydroquinone are given in Table 1. Except where otherwise noted, data are given for materials in their, Hydroquinone oxidation with V2O5/NaClO3/H2SO4, http://www.sciencemadness.org/smwiki/index.php?title=Hydroquinone&oldid=11523, Articles containing unverified chemical infoboxes, GNU Free Documentation License 1.3 or later. [Na+].OC(=O)CN(CC([O-])=O)CCN(CC(O)=O)CC([O-])=O, trimethyl-[phenyl-bis(trimethylsilyloxy)silyl]oxysilane, C[Si](C)(C)O[Si](O[Si](C)(C)C)(O[Si](C)(C)C)C1=CC=CC=C1, C\C(=C/C=O)\C=C\C=C(\C=C\C1=C(CCCC1(C)C)C)/C, 1-hexadecanoyl-2-(9Z,12Z-octadecadienoyl)-sn-glycero-3-phosphocholine, CCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCC[N+](C)(C)C)OC(=O)CCCCCCC\C=C/C\C=C/CCCCC, 2-[2-[2-[2-[2-[2-(2-dodecoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethanol, C[Si]1(C)O[Si](C)(C)O[Si](C)(C)O[Si](C)(C)O[Si](C)(C)O1, O=C1C(=O)C(C2=CNC3=C(C(C(=O)C4=C32)=O)C)=C2C4=CNC2=C1C, [Na+].[Na+].[Na+]. endstream endobj 1 0 obj <> endobj 2 0 obj <> endobj 12 0 obj <>stream GHS P Statement: Wear protective gloves/protective clothing/eye protection/face protection.Call a POISON CENTER or doctor/physician if you feel unwell.IF ON SKIN: Gently wash with plenty of soap and water.IF IN EYES: Rinse cautiously with water for several minutes. This range of pH has been preferred for hydroquinone compositions, because it has been believed that the hydroquinone is less likely to excessively discolor under acid conditions. Unfortunately, retinoids, in particular retinoic acid, retinal, and their derivatives, isomers and analogs (such as adapalene, tazarotene and isotretoin) also have discoloration problems due to oxidation. It is found in wheat, rye, and barley.It is a precursor to diverse industrial products including polymers and plasticizers, as well as being a component of a number of hair and skin conditioners. The correlation coefficient is greater than 0.9937 for one of these two equations for the binary studied systems where the solvent is either water or 1-octanol. Canon Tests, which results are detailed in the following two tables, are performed to show how well sodium metabisulfite ("SMBS") stabilizes color at each pH at 5C and 40C in 4% hydroquinone ("HQ") compositions. Hydroquinone is an aromatic organic compound which is currently used in two main sectors: . 1401417, Country of ref document: The disodium diphenolate salt of hydroquinone is used as an alternating comonomer unit in the production of the polymer PEEK. Phillip M. Hudnall "Hydroquinone" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. Toughness of the polymer increases due to the presence of flexible units in the backbone such as long chain diols (e.g., diethylene glycol, dipropylene glycol, triethylene glycol) or long chain saturated acids (e.g., adipic . ADS J. Pharm. Variations in pH have proven to result in excessive discoloration ranging from brownish to black. The protective system can be an entrapment system, a single or multi- laminar system, such as by the formation of vesicles such as a liposome or by utilizing wax, paraffin, silicone, polyethylene, or any material or system which protects the retinoid from oxidation. Thank you for your inquiry and interest in ChemPoint. Anal. We have found that a cream containing 5% of hydroquinone and 0.05 % of laevo-ascorbic acid remains white, and the emulsion remains unbroken after many months of storage, The laevo-ascorbic or cevitamic acid is pr'eferably employed in the free condition; but if desired, the salts, and especially the water-soluble salts thereof, may be employed . Other antioxidants, for example cationic salts of acidic ascorbyl esters, most preferably magnesium ascorbyl phosphate, aminopropyl ascorbyl phosphate, and sodium ascorbyl phosphate, have not been utilized in combination with hydroquinone in view of the acidic pH, generally from about 3.4 to about 3.5, and the recommended pH range for magnesium ascorbyl phosphate is about 7.0 to 8.5. Treatment with hydroquinone interferes with the action of tyrosinase, which is an enzyme used in the synthesis of melanin, and compositions are sold across the counter at about 2% hydroquinone and by prescription at higher concentrations. The experimental solubility data was well-correlated with the data, calculated by . The reservoir opens through a muscle-controlled valve onto a thick-walled reaction chamber. hydroquinone, 1,4-benzenediol, quinol, 1,4-dihydroxybenzene, p-benzenediol, 4-hydroxyphenol, p-hydroquinone, p-hydroxyphenol, p-dihydroxybenzene, benzoquinol, Electrophoresis, Western Blotting and ELISA, Chromatography and Mass Spectrometry Reagents, Laboratory Syringe Needles and Accessories, Lab Coats, Aprons, and Other Safety Apparel, Sharps Disposal Containers and Accessories, Classroom Laboratory Supplies and Consumables, Applied Biosystems TaqMan Assay and Arrays Search Tool, Applied Biosystems TaqMan Custom Assay Design Tools, Applied Biosystems Custom qPCR Primers and TaqMan Probes Tool, Chemical Storage and Management Resource Center, Solubility in water: 70g/L in water (20C). 0 7 r @ &. Classical photo shops . Methylaminophenol, used in photography, is produced in this way:[8]. The amount of crosslinking was controlled by the reaction conditions, including temperature, reaction time, and . GHS H Statement: Causes serious eye damage.Suspected of causing genetic defects.May cause an allergic skin reaction.Suspected of causing cancer.Harmful if swallowed.Very toxic to aquatic life. Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. HYPERPIGMENTARY STAIN ELIMINATING CREAM FOR FACE SKIN AND ITS USE. Thanks to the added vitamin E, it leaves your skin feeling smooth and soft, too. S.C. Gad, T. Pham, in Encyclopedia of Toxicology (Third Edition), 2014 Environmental Fate and Behavior. Do not put this product in the microwave. Water Solubility 73000 mg/L at 25C 2.6B pH pKa 4.0 - 4.7 pK1 = 9.9 2.12 Oxidation:Reduction Potential +286 mV at 25C and pH 7 ENVIRONMENTAL FATE/BIODEGRADATION J. Chem. ;O,1Y+%8#oKT^VWtew4>@V.SR :hmBZ>#ey!UC5! / /n Then add it to the ingredients. fungichromin having five-membered rings with one oxygen as the only ring hetero atom, e.g. The Campaign for Safe Cosmetics has also highlighted concerns. ORIGINAL CODE: 0009013, Ref document number: Compositions according to this invention may include additives or components to enhance the skin penetration of its ingredients. 114, 175188 (1996), I. Hahnenkamp, G. Graubner, J. Gmehling, Int. n3kGz=[==B0FX'+tG,}/Hh8mW2p[AiAN#8$X?AKHI{!7. Recent pieces of . [21] The FDA officially banned hydroquinone in 2020 as part of a larger reform of the over-the-counter drug review process. Availability. Chem. Hydroquinone, like phenols are very weak acids and can be deprotonated. 0000053439 00000 n The Density of hydroquinone is . Chim. The present invention combats this problem, with hydroquinone compositions in the neutral pH range, preferably a pH of from about 5.5 to about 8.0, more preferably a pH of from about 5.5 to about 7.5, and most preferably at a pH of from about 6.0 to about 7.5. 38, 40814091 (1999), J. Qingzhu, M. Peisheng, Y. Shouzhi, W. Qiang, W. Chang, L. Guiju, J. Chem. If youre making your lotion. Privacy Policy. There are various other uses associated with its reducing power. The solubilities of benzoic acid, salicylic acid, resorcinol and hydroquinone in water and in 1-octanol were measured by the dynamic method which is also called the synthetic method from 297.25K to 334.45K. Using differential scanning calorimetry (DSC Q2000 and SDT Q600), the melting temperature and the enthalpy of fusion of these solutes were determined. At 40C, 4% hydroquinone compositions have the same color stability with slightly more sodium metabisulfite, at least about 0.01% at about 3.5 to about 4.0 pH; at least about 0.05% sodium metabisulfite at about 4.5 to about 6.0 pH; and at pH; at least about 0.05% sodium metabisulfite at about 4.5 to about 6.0 pH; and at least about 0.10% sodium metabisulfite at about 6.5 to about 7.0 pH. This invention addresses the problem of formulating a pigmentation disorder treatment composition with hydroquinone without an excessive discoloration of the composition in the pH range of about 7.0. Preferably, the protected retinoid, in particular retinoic acid, retinal, and their derivatives, isomers and analogs (such as adapalene, tazarotene and isotretoin), is in the form of small beads or spheres suitable for incorporation into a topical composition. Crit. Editor's Rating: and our These can be burning, redness, sensitization and irritation in some patients. Hydrogen peroxide is used and the reaction gives a mixture of hydroquinone and catechol: An accessible route involves the reaction of sodium hydroxide with 1,4-dichlorobenzene. stearic, palmitic, arachidic acids, Heterocyclic compounds having oxygen as the only ring hetero atom, e.g. Some may double boil the hydroquinone and ester, I was too scared of the possibility of combustion. 2023 Springer Nature Switzerland AG. I would like to add retinol and kojic acid to it as well. It is a reducmg agent that is reversibly oxidized to semiquinone and quinone. It has a white-solid appearance. While patients suffer from pigmentation disorders, they may also suffer from other skin disorders and signs of aging, including but not limited to rough skin texture, mottled pigmentation, sallow complexion, lines and wrinkles. If youd like my help or recipes for this bleaching cream please contact me on Instagram @kaylinell and @kay.linell or Facebook at kay linell. The toxicology of hydroquinone - relevance to occupational and environmental exposure. Other adverse effects Hydroquinone is combustible when preheated. Hope it helps 6 yrs later. For more information, please see our The FDA had classified hydroquinone in 1982 as a safe product - generally recognized as safe and effective (GRASE), however additional studies under the National Toxicology Program (NTP) were suggested in order to determine whether there is a risk to humans from the use of hydroquinone. The color stability of the hydroquinone composition is promoted by one or more antioxidants in the hydroquinone phase, preferably sulfite, including but not limited to sulfites, bisulfites, metabisulfites, their salts and their derivatives, most preferably sodium metabisulfite, and a cationic salt of acidic ascorbyl esters, most preferably magnesium ascorbyl phosphate. If you are already a ChemPoint customer then sign up for access to our online ordering website. Human exposure to hydroquinone can occur by dietary, occupational, and environmental sources. With respect to organic solvents, the solubility varies from 57% in ethanol to less than 0.1% in benzene. HYDROQUINONE (hahy droh kwi NOHN) is applied to the the skin to lighten areas that have darkened. Why we like it: This affordable cream contains 2 percent hydroquinone, sunscreen, and costs around five dollars. 2017-02-16T10:10:56+01:00 Eng. Eye Contact Rinse immediately with plenty of water, also under the eyelids, for at least 15 minutes. Have an order or account question, find answers in our Online Support articles. 0000003430 00000 n uuid:a150f3fd-7f22-4439-aa26-6f445f4017e5 endstream endobj 276 0 obj <>stream The composition is preferably formulated in separate phases as designated below. nQt}MA0alSx k&^>0|>_',G! 20, 14331442 (1986), G. Wienke, J. Gmehling, Toxicol. vz >I d50dwp?i4,H3. Such carriers are widely known in the art and deliver the composition's ingredients to the skin without excessive degradation, inactivation or other unwanted interaction.
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