NANOMATERIALS AND COSMETICS

Year 2012, Volume: 1 Issue: 42(1), 43 - 70, 10.01.2014

E. Alğın Yapar Ö. İnal E. Alğin Yapar1,*, Ö. İnal2 E. Alğın Yapar1,*, Ö. İnal2

Abstract

This review has overviewed the nanotechnology approaches and safety
concerns in cosmetics. Nanotechnology based nanomaterials have been widely
use in cosmetics for recent few years such as in sunscreens, hair products,
skincare products, etc. However debate on their definition and insufficient
quantification methods are major problems still occur in the nanomaterial
field. Moreover the frequent use of cosmetics, safety of nanoscale ingredients
of them has gain importance mainly by means of their dermal exposure.
Although the proposed benefits that may occur by incorporating nanoparticles
in cosmetics are increased efficiency, transparency, unique texture, protection
of active ingredient, and overall higher consumer compliance, there still
have not enough studies proved whether they are completely safe or not.
As a conclusion major issues related nanomaterials such as developing,
using and researching is going to increase in the near future due to their
economically importance.

Keywords

Nanotechnology, nanomaterial, dermal, safety, cosmetics

NANOMATERIALS AND COSMETICS

Abstract

This review has overviewed the nanotechnology approaches and safety concerns in cosmetics. Nanotechnology based nanomaterials have been widely use in cosmetics for recent few years such as in sunscreens, hair products, skincare products, etc. However debate on their definition and insufficient quantification methods are major problems still occur in the nanomaterial field. Moreover the frequent use of cosmetics, safety of nanoscale ingredients of them has gain importance mainly by means of their dermal exposure. Although the proposed benefits that may occur by incorporating nanoparticles in cosmetics are increased efficiency, transparency, unique texture, protection of active ingredient, and overall higher consumer compliance, there still have not enough studies proved whether they are completely safe or not. As a conclusion major issues related nanomaterials such as developing, using and researching is going to increase in the near future due to their economically importance.

Keywords

Nanotechnology, nanomaterial, dermal, safety, cosmetics

References

• 1. Chanchal, D., Swarnlata, S. (2008). Novel approaches in herbal cosmetics. J Cosmet Dermatol. 7(2): 89-95.
• 2. Alğın Yapar, E., İnal Ö., Erdal, S. (2013). Design and in vivo evaluation of emulgel formulations including green tea extract and rose oil”. Acta Pharmaceutica, (inpress).
• 3. Mihranyan, A., Ferraz, N., Stromme, M. (2012). Current status and future prospects of nanotechnology in cosmetics. Progress in Materials Science, 57: 875-910.
• 4. Kreyling, W.G., Semmler-Behnke, M., Chaudhry, Q. (2010). A complementary definition of nanomaterial. Nano Today, 5: 165–168.
• 5. Maynard, A.D. Don’t define nanomaterials. (2011). Nature, 475(7354): 31.
• 6. Singh, P., Nanda, A. (2012). Nanotechnology in cosmetics: a boon or bane? Toxicological & Environmental Chemistry, 94(8): 1467–1479.
• 7. Hosokawa, M., Nogi, K., Naito, M., Yokoyama, T. (2007). Development of functional skincare cosmetics using biodegradable PLGA nanospheres. In: Hosokawa, M., Nogi, K., Naito, M., Yokoyama, T. (Eds.), Nanoparticle Technology Handbook, Elsevier Science, Oxford, pp. 501–506.
• 8. Mu, Li., Sprando, R.L. (2010). Application of nanotechnology in cosmetics. Pharm Res, 27: 1746–1749
• 9. Papakostas, D., Rancan, F., Sterry, W., Blume-Peytavi, U., Vogt, A. (2011). Nanoparticles in dermatology. Arch Dermatol Res, 303: 533– 550.
• 10. Otberg, N., Richter, H., Schaefer, H., Blume-Peytavi, U., Sterry, W., Lademann, J. (2004). Variations of hair follicle size and distribution in different body sites. J Invest Dermatol, 122: 14–19.
• 11. Prow, T.W., Grice, J.E., Lin, L.L., Faye, R., Butler, M., Becker, W., Wurm, E.M., Yoong, C., Robertson, T.A., Soyer, H.P., Roberts, M.S. (2011). Nanoparticles and microparticles for skin drug delivery. Adv Drug Deliv Rev, 63(6): 470-91.
• 12. Borm, P.J.A., Robbins, D., Haubold, S., Kuhlbusch, T., Fissan, H., Donaldson, K., Schins, R., Stone, V., Kreyling, W., Lademann, J., Krutmann, J., Warheit, D., Oberdorster, E. (2006). The potential risks of nanomaterials: a review carried out for ECETOC. Particle and Fibre Toxicology, 3:11-46.
• 13. Robert W. Lee, Dinesh B. Shenoy, Rajiv Sheel. Micellar Nanoparticles: Applications for Topical and Passive Transdermal Drug Delivery. (2010). In: Handbook of Non-Invasive Drug Delivery Systems NonInvasive and Minimally-Invasive Drug Delivery Systems for Pharmaceutical and Personal Care Products Ed: Vitthal S. Kulkarni. Elsevier, Oxford, UK pp: pp:37-58.
• 14. Wissing, S.A., Muller, R.H. (2003). The influence of solid lipid nanoparticles on skin hydration and viscoelasticity in vivo study. European Journal of Pharmaceutics, 1: 67–72.
• 15. Cevc, G., Vierl, U. (2010). Nanotechnology and the transdermal route: A state of the art review and critical appraisal. J Control Release, 141(3): 277-99.
• 16. Alves, M.P., Scarrone, A.L., Santos, M., Pohlmann, A.R., Guterres, S.S. (2007). Human skin penetration and distribution of nimesulide from hydrophilic gels containing nanocarriers. Int J Pharm, 341: 215–220.
• 17. Kristl, J., Teskac, K., Grabnar, P.A. (2010). Current view on nanosized solid lipid carriers for drug delivery to the skin. J Biomed Nanotechnol, 6(5): 529–542.
• 18. Saupe, A., Wissing, S.A., Lenk, A., Schmidt, C., Muller, R.H. (2005). Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC)– structural investigations on two different carrier systems. Biomed Mater Eng, 15: 393–402.
• 19. Schafer-Korting, M., Mehnert, W., Korting, H.C. (2007). Lipid nanoparticles for improved topical application of drugs for skin diseases. Adv Drug Deliv Rev, 59: 427–443.
• 20. Pardeike, J., Hommoss, A., Muller, R.H. (2009). Lipid nanoparticles (SLN, NLC) in cosmetic and pharmaceutical dermal products. Int J Pharm, 366: 170–184.
• 21. Uner, M. Wissing, S.A., Yener, G., Müller, R.H. (2005). Skin moisturizing effect and skin penetration of ascorbyl palmitate entrapped in solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) incorporated into hydrogel. Pharmazie, 60 (10):751–755.
• 22. Chirico, F., Fumelli, C., Marconi, A., Tinari, A., Straface, E., Malorni, W., Pellicciari, R., Pincelli, C. (2007). Carboxyfullerenes localize within mitochondria and prevent the UVB-induced intrinsic apoptotic pathway. Exp Dermatol, 16: 429–436.
• 23. Kato, S., Taira, H., Aoshima, H., Saitoh, Y., Miwa, N. (2010). Clinical evaluation of fullerene-C60 dissolved in squalane for antiwrinkle cosmetics. J Nanosci Nanotechnol, 10(10): 6769–6774.
• 24. Gupta, U., Agashe, H.B., Asthana, A., Jain, N.K. (2006). A review of in vitro-in vivo investigations on dendrimers: the novel nanoscopic drug carriers. Nanomedicine, 2(2): 66-73.
• 25. Tolia, G.T., Choi, H.H. (2008). The role of dendrimers in topical drug E. ALĞIN YAPAR, Ö. İNAL 63 delivery. Pharmaceutical Technology, 32(11): 88-89.
• 26. Venuganti, V.V., Perumal, O.P. (2009). Poly(amidoamine) dendrimers as skin penetration enhancers: Influence of charge, generation, and concentration. J Pharm Sci, 98: 2345–2356.
• 27. Zulli, F. Preparation and properties of coenzyme Q10 nanoemulsions. (2006).Cosmet Sci Technol, 1: 1-7.
• 28. Guglielmini, G. (2008). Nanostructured novel carrier for topical application. Clin Dermatol, 26: 341-6.
• 29. Merisko, L.E., Liversidge, G.G., Cooper, E.R. (2003).Nanosizing: a formulation approach for poorly-water-soluble compounds. Eur J Pharm Sci, 2: 113–20.
• 30. Shegokar, R., Keck, C. M., Müller, R. H., Gohla, S. (2011). Cosmetic nanocrystals: products and dermal effects, P 123, 6th Polish-German Symposium on Pharmaceutical Sciences: Perspectives for a new decade,Düsseldorf, 20-21 May 2011.
• 31. Peterson, R. (2006). Nanocrystals for use in topical cosmetic formulations and method of production thereof. US Patent Application No. 60/8866, 233.
• 32. Al Shaal, L., Shegokar, R., Müller, R.H. (2011). Production and characterization of antioxidant apigenin nanocrystals as a novel UV skin protective formulation. Int J Pharm., 420(1):133-40.
• 33. Bansal, S., Bansal, M., Kumria, R. (2012). Nanocrystals: Current Strategies and Trends. Int. J. Res.Pharm.Biomed. Sci, 3(1): 406-419.
• 34. Shegokar R., Müller, R.H. (2010). Nanocrystals: industrially feasible multifunctional formulation technology for poorly soluble actives. Int. J. Pharm, 399(1-2): 129–139.
• 35. Prashar, D., Sharma, D. (2011). Cubosomes: A sustained drug delivery carrier. Asian J. Res. Pharm. Sci., 1(3): 59-62.
• 36. Embil, K., Nacht, S. (1996). The microsponge delivery system (MDS):a topical delivery system with reduced irritancy incorporating multiple triggering mechanisms for the release of actives. J Microencapsul, 13: 575–88.
• 37. Zhou, M., Nakatani, E., Gronenberg, L.S., Tokimoto, T., Wirth, M.J., Hruby, V.J., Roberts, A., Lynch, R.M., Ghosh, I. (2007). Peptidelabeled 64 Nanomaterials and Cosmetics quantum dots for imaging GPCRs in whole cells and as single molecules. Bioconjug Chem, 18: 323–332.
• 38. Jenning, V., Gysler, A., Schafer-Korting, M., Gohla, S.H. (2000). Vitamin A loaded solid nanoparticles for topical use: occlusive properties and drug targeting to the upper skin. Eur J Pharm Biopharm, 49(3): 211–218.
• 39. Müller, R.H., Dingler, A. (1998). The next generation after the liposomes: solid lipid nanoparticles (SLN, Lipopearls) as dermal carrier in cosmetics. Eurocosmetics, 7: 19–26.
• 40. Alvarez-Roman, R., Barré, G,, Guy, R.H., Fessi, H. (2001). Biodegradable polymer nanocapsules containing a sunscreen agent: preparation and photoprotection. Eur. J. Pharm. Biopharm, 52: 191–195.
• 41. de Vringer, T., de Ronde, H.A. (1995). Preparation and structure of a water-in-oil cream containing lipid nanoparticles, J. Pharm. Sci. 84(4): 466–472.
• 42. Müller, R.H. Mader, K. Gohla, S. (2000). Solid lipid nanoparticles (SLN) for controlled drug delivery—a review of the state of the art. Eur. J. Pharm. Biopharm, 50: 161–177.
• 43. Gonzalez, S., Fernandez-Lorente, M., Gilaberte-Calzada, Y. (2008). The latest on skin photoprotection. Clin Dermatol, 26: 614–626.
• 44. Durand, L., Habran, N., Henschel, V., Amighi, K. (2010). Encapsulation of ethylhexyl methoxycinnamate, a light-sensitive UV filter, in lipid nanoparticles. J Microencapsul, 27(8): 714–725.
• 45. Xia, Q., Saupe, A., Muller, R.H., Souto, E.B. (2007). Nanostructured lipid carriers as novel carrier for sunscreen formulations. Int J Cosmet Sci, 29: 473–482.
• 46. Lademann, J., Richter, H., Golz, K., Zastrow, L., Sterry, W., Patzelt, A. (2008). Influence of microparticles on the homogeneity of distribution of topically applied substances. Skin Pharmacol Physiol, 21: 274–282.
• 47. Lademann, J., Rudolph, A., Jacobi, U., Weigmann, H.J., Schaefer, H., Sterry, W., Meinke, M. (2004). Influence of nonhomogeneous distribution of topically applied UV filters on sun protection factors. J Biomed Opt, 9: 1358–1362.
• 48. de Fine Olivarius, F., Hansen, A.B., Karlsmark, T., Wulf, H.C. (1996). E. ALĞIN YAPAR, Ö. İNAL 65 Water protective effect of barrier creams and moisturizing creams: a new in vivo test method. Contact Dermatitis, 35: 219–225.
• 49. Kluijtmans, S., Bouwstra, J.B. (2007). Dendrimer-aminobutadienebased UV-screens, European patent 1,784,455, May 16, 2007.
• 50. Bahary W.S., Hogan. M.P. (1997). Cleansing Compositions with Dendrimers as Mildness Agents. US Patent 5,658,574, August 19, 1997.
• 51. Forestier, S. Rollat-Corvol, I. (1999). Deodorant Composition and Use Thereof. US Patent 6,001,342, December 14, 1999.
• 52. Allard D., Forestier, S. (2002). Self-Tanning Cosmetic Compositions, US Patent 6,399,048, June 4, 2002.
• 53. Gokce EH, Korkmaz E, Tuncay-Tanrıverdi S, Dellera E, Sandri G, Bonferoni MC, Ozer O. A comparative evaluation of coenzyme Q10- loaded liposomes and solid lipid nanoparticles as dermal antioxidant carriers. Int J Nanomedicine. 7: 5109-17.
• 54. Farboud ES, Nasrollahi SA,Tabbakhi Z. (2011). Novel formulation and evaluation of a Q10-loaded solid lipid nanoparticle cream: in vitro and in vivo studies. Int J Nanomedicine, 6: 611-7.
• 55. Dingler, A. (1998). Feste Lipid-Nanopartikel als kolloidale Wirstoffträgersysteme zur dermalen Applikation. Institut für Pharmazie. Freie Universität, Berlin.
• 56. Teeranachaideekul, V., Müller, R.H., Junyaprasert, V.B., (2007). Encapsulation of ascorbyl palmitate in nanostructured lipid carriers (NLC)— effects of formulation parameters on physicochemical stability. Int. J. Pharm, 340(1-2): 198–206.
• 57. Dingler, A., Blum, R.P., Niehus, H., Müller, R.H., Gohla, S. (1999). Solid lipid nanoparticles (SLN/Lipopearls)—a pharmaceutical and cosmetic carrier for the application of vitamin E in dermal products, J. Microencapsul 16(6): 751–767.
• 58. Jenning, V., Gohla, S.H. (2001). Encapsulation of retinoids in solid lipid nanoparticles (SLN). J. Microencapsul. 18(2): 149–158.
• 59. Jee, J.P., Lim, S.J., Park, J.S., Kim, C.K. (2006). Stabilization of all-trans retinol by loading lipophilic antioxidants in solid lipid nanoparticles. Eur. J. Pharm. Biopharm. 63: 134–139.
• 60. Wissing, S.A., Lippacher, A., Müller, R. (2001). Investigations on the 66 Nanomaterials and Cosmetics occlusive properties of solid lipid nanoparticles (SLN). J. Cosmet. Sci. 52: 313–324.
• 61. de Vringer, T., (1999). Topical preparation containing a suspension of solid lipid particles. USA patent 91-200,664.
• 62. Souto, E.B., Wissing, S.A., Barbosa, C.M., Müller, R.H. (2004). Development of a controlled release formulation based on SLN and NLC for topical clotrimazole delivery. Int. J. Pharm. 278: 71–77.
• 63. Wissing, S.A., Müller, R.H. (2003). The influence of solid lipid nanoparticles on skin hydration and viscoelasticity—in vivo study. Eur. J. Pharm. Biopharm. 56: 67–72.
• 64. Teeranachaideekul, V., Souto, E.B., Junyaprasert, V.B., Müller, R.H. (2007). Cetyl palmitate-based NLC for topical delivery of Coenzyme Q(10)—development, physicochemical characterization and in vitro release studies. Eur. J. Pharm. Biopharm. 67: 141–148
• 65. Pardeike, J., Müller, R.H. (2007). Coenzyme Q10 loaded NLCs: preparation, occlusion properties and penetration enhancement. Pharm. Technol. Eur. 19: 46–49.
• 66. Müller, R.H., Immig, H., Hommoss, A. (2007). Prolonged release of parfumes by nanolipid carriers (NLC) technology. Eur. Cosmetics 15(11-12): 10-15.
• 67. Hommoss, A., Car, S., Kim, C., Müller, R.H. (2007). Prolonged release of perfume from nanostructured lipid carriers (NLC). Abstract in the Annual Meeting of the American Association of Pharmaceutical Scientists (AAPS), San Diego, USA.
• 68. Müller, R.H., Radtke, M., Wissing, S.A. (2002). Solid lipid nanoparticles (SLN) andnanostructured lipid carriers (NLC) in cosmetic and dermatological preparations. Adv. Drug Deliv. Rev. 54(1): 131–155.
• 69. Wissing, S.A., Müller, R.H. (2002). Solid lipid nanoparticles as carrier for sunscreens: in vitro release and in vivo skin penetration. J. Control. Release, 81: 225–233.
• 70. Song, C., Liu, S. (2005). A new healthy sunscreen system for human: solid lipid nanoparticles as carrier for 3,4,5-trimethoxybenzoylchitin and the improvement by adding Vitamin E. Int. J. Biol. Macromol, 36: 116–119. E. ALĞIN YAPAR, Ö. İNAL 67
• 71. Wissing, S.A., Müller, R.H. (2003). Cosmetic applications for solid lipid nanoparticles (SLN). Int. J. Pharm, 254: 65–68.
• 72. Villalobos-Hernandez, J.R., Müller-Goymann, C.C. (2005). Novel nanoparticulate carrier system based on carnauba wax and decyl oleate for the dispersion of inorganic sunscreens in aqueous media. Eur. J. Pharm. Biopharm. 60: 113–122.
• 73. Müller, R.H., Petersen, R.D., Hommoss, A., Pardeike. J. (2007). Nanostructured Lipid Carriers (NLC) In Cosmetic Dermal Products. Advanced Drug Delivery Reviews, 59: 522–530.
• 74. Souto, E.B., Muller, R.H., Gohla, S. (2005). A novel approach based on lipid nanoparticles (SLN) for topical delivery of alpha-lipoic acid. J Microencapsul, 6: 581–92.
• 75. Martorano, L.M., Stork, C.J., Li, Y.V. (2010). UV irradiation-induced zinc dissociation from commercial zinc oxide sunscreen and its action in human epidermal keratinocytes. Journal of Cosmetic Dermatology, 9: 276–286.
• 76. Tyner, K.M., Wokovich, A.M., Godar, D.E., Doub, W.H., Sadrieh, N. (2011). The state of nano-sized titanium dioxide (TiO2) may affect sunscreen performance. International Journal of Cosmetic Science, 33: 234–244.
• 77. Nipane, D., Thakare S.R., Khati N.T. (2012). ZnO nanoparticle by sol-gel and its UV application in cosmetics formulation. International Journal of Knowledge Engineering, 3(1):168-169.
• 78. Macwan, D.P., Dave, P.N., Chaturvedi, S. (2011). A review on nanoTiO2 sol-gel type syntheses and its applications. J Mater Sci, 46: 3669-3686.
• 79. Weir, A., Westerhoff, P., Fabricius, L., Hristovski, K., von Goetz, N. (2012). Titanium dioxide nanoparticles in food and personal care products. Environ. Sci. Technol., 46(4): 2242–2250.
• 80. Fratter, A., Se menzato, A. (2011). New association of surfactants for the production of food and cosmetic nanoemulsions: preliminary development and characterization. International Journal of Cosmetic Science, 33: 443–449.
• 81. Kabri, T., Arab-Tehrany, E., Belhaj N., Linder, M. (2011). Physico-che- 68 Nanomaterials and Cosmetics mical characterization of nanoemulsions in cosmetic matrix enriched on omega-3. Journal of Nanobiotechnology 9(41): 1-8.
• 82. Taufikurohmah, T., Sanjaya, I.G.M., Syahrani, A. (2011). Nanogold Synthesis Using Matrix Mono Glyceryl Stearate as Antiaging Compounds in Modern Cosmetics. Journal of Materials Science and Engineering, 11: 857-864.
• 83. Kang, K., Lee, C., Pyo, H., Jeong, N. (2005). Preparation and Characterization of Nano-Liposomes Using Phosphatidylcholine. Journal of Industrial and Engineering Chemistry 11(6): 847-851.
• 84. Schmid, D., Zulli, F. (2005). Role of beta endorphin in the skin. Int J Appl Sci, 131: 2-4.
• 85. Pople, P.V., Singh, K.K. (2006). Development and evaluation of topical formulation containing solid lipid nanoparticles of vitamin A. AAPS Pharm Sci Tech,7: 1–7.
• 86. Gulson, B., McCall, M., Korsch, M., Gomez, L., Casey, P., Oytam, Y., Taylor, A., McCulloch, M., Trotter, J., Kinsley, L., Greenoak, G. (2010). Small amounts of zinc from zinc oxide particles in sunscreens applied outdoors are absorbed through human skin. Toxicol Sci, 118(1): 140–149.
• 87. Lademann, J., Richter, H., Teichmann, A., Otberg, N., Blume-Peytavi, U., Luengo, J., Weiss, B., Schaefer, U.F., Lehr, C.M., Wepf, R., Sterry, W. (2007). Nanoparticles—an efficient carrier for drug delivery into the hair follicles. Eur J Pharm Biopharm 66: 159– 164.
• 88. Toll, R., Jacobi, U., Richter, H., Lademann, J., Schaefer, H., BlumePeytavi, U. (2004). Penetration profile of microspheres in follicular targeting of terminal hair follicles. J Invest Dermatol, 123: 168–176.
• 89. Cross, S.E., Innes, B., Roberts, M.S., Tsuzuki, T., Robertson, T.A., McCormick, P. (2007). Human skin penetration of sunscreen nanoparticles: in vitro assessment of a novel micronized zinc oxide formulation. Skin Pharmacol Physiol, 20: 148–154.
• 90. Newman, M.D., Stotland, M., Ellis, J.I. (2009). The safety of nanosized particles in titanium dioxide- and zinc oxide-based sunscreens. J Am Acad Dermatol, 61: 685–692.
• 91. Alvarez-Roman, R., Naik, A., Kalia, Y.N., Guy, R.H., Fessi, H. (2004). E. ALĞIN YAPAR, Ö. İNAL 69 Skin penetration and distribution of polymeric nanoparticles. J Control Release, 99: 53-62.
• 92. Graf, C., Meinke, M., Gao, Q., Hadam, S., Raabe, J., Sterry, W., Blume-Peytavi, U., Lademann, J., Ruhl, E., Vogt, A. (2009). Qualitative detection of single submicron and nanoparticles in human skin by scanning transmission X-ray microscopy. J Biomed Opt, 14(2): 021015.
• 93. Jiang, S.J., Chen, J.Y., Lu, Z.F., Yao, J., Che, D.F., Zhou, X.J. (2006). Biophysical and morphological changes in the stratum corneum lipids induced by UVB irradiation. J Dermatol Sci, 44: 29–36.
• 94. Yamamoto, T., Kurasawa, M., Hattori, T., Maeda, T., Nakano, H., Sasaki, H. (2008). Relationship between expression of tightjunction-related molecules and perturbed epidermal barrier function in UVB-irradiated hairless mice. Arch Dermatol Res, 300: 61–68.
• 95. Li, Y., H. Zhang, C. Guo, G. Hu, H. Du, M. Jin, P. Huang, Z. Sun, and W. Yang. (2012). Cytotoxicity and DNA damage effect of TGA_trapped CdTe quantum dots. Chemical Research in Chinese Universities, 28: 276–81.
• 96. Van, R.I. (2006). Beyond skin feel: innovative methods for developing complex sensory profiles with silicones. J Cosmet Dermatol 5: 61–67.
• 97. Nohynek, G.J., Dufour, E.K. (2012). Nano-sized cosmetic formulations or solid nanoparticles in sunscreens: A risk to human health? Arch Toxicol, 86: 1063–1075.
• 98. Sumner, S.C. (2010). Distribution of carbon-14 labeled C60[(14C)]in the pregnant and in the lactating dam and the effect of C60 exposure on the biochemical profile of urine. Journal of Applied Toxicology, 30: 354–60.
• 99. Yamashita, K. (2011). Silica and titanium dioxide nanoparticles cause pregnancy complications in mice. Nature Nanotechnology, 6: 321–28.
• 100.Jacobs, J.F., van de Poel, I., Osseweijer, P. (2010). Sunscreens with Titanium Dioxide (TiO2) Nano-Particles:A Societal Experiment. Nanoethics 4: 103–113.
• 101. Sayes, C.M., Fortner, J.D., Guo, W., Lyon, D., Boyd, A.M., Ausman, K.D., Tao, Y.J., Sitharaman, B., Wilson, L.J., Hughes, J.B., Colvin, West, J.L., V.L. (2004). The differential cytotoxicity of water-soluble 70 Nanomaterials and Cosmetics fullerenes. Nano Letters, 4: 1881-1887.
• 102.Kokura, S., Handa, O., Takagi, T., Ishikawa, T., Naito, Y., Yoshikawa, T. (2010). Silver nanoparticles as a safe preservative for use in cosmetics. Nanomedicine: Nanotechnology, Biology, and Medicine, 6: 570–574.
• 103.Henkler, F., Tralau, T., Tentschert, J., Kneuer, C., Haase, A., Platzek, T., Luch, A., Götz, M.E. (2012). Risk assessment of nanomaterials in cosmetics: a European union perspective. Arch Toxicol. 86(11): 1641–1646.
• 104. Pozzi-Mucelli, S., Balharry, D., Stone, V. (2013). Intelligent testing strategy for engineered nanomaterials. Environmental Health & Safety, 3: 493-496.
• 105. Sharma, A., Kumar.M, S., Mahadevan, N. (2012). Nanotechnology: A promising approach for cosmetics. Int J Recent Adv Pharm Res, 2(2): 54-61.