Filtri Solari: Tipologie chimico-fisiche, Funzionalità, compatibilità ed incompatibilità SICC Seminario Tecnico 26 e 27 febbraio 2015 Carmina Casas ([email protected]) The Sun The Sun is the star at the center of the Solar System. Sunlight is by far the most important source of energy for life on Earth. Directly and indirectly, all living things depend on the sun. But how this energy reaches the planet? by nuclear fusion (converts hydrogen into helium) E = hc/(λ) E = Energy (Jules) h = Planck constant (~6.626 × 10-34J·s) c = speed of light in vacuum (~3x108m/s) λ = wavelength (m) The spectrum of solar light at the Earth's surface cosmic gamma X-ray UV visible infrared micro radio radiation radiation radiation radiation light radiation waves waves medium short wave long wave visible UV- vacuum wave UVC UVA light UVB 200 230 260 290 320 350 380 410 wave length in nm The spectrum of solar light at the Earth's surface The spectrum of solar light at the Earth's surface is mostly spread across the visible and near-infrared ranges with a small part in the near- ultraviolet The spectrum of solar light at the Earth's surface Radiation λ (nm) % UV-B 290-320 0.1 UV-A 320-400 4.9 Visible 400-760 39 Infra-red 760-3000 56 The spectrum of solar light at the Earth's surface UV-C UV-B UV-A(II) UV-A(I) 1 0.9 0.8 0.7 0.6 0.5 ENERGY SKIN 0.4 PENETRATION 0.3 0.2 0.1 0 200 220 240 260 280 300 320 340 360 380 400 Wavelength (nm) Ozone layer depletion Ozone can be destroyed by a number of free radical catalysts Steady decline of about 4% per decade The effects of the depletion: increases the surface UV radiation affecting the human health A reduction by 10% the density of the ozone layer may produce in the world: • 300 000 new skin cancers (carcinomas) • 4 500 new melanoma cancers • 2 millions new ocular cataracts Sun Effects POSITIVE: Stimulates physical and mental health Production of the VITAMIN D3: essential for the absorption of calcium in the bones Treatment of metabolic diseases Atopic Dermatitis, Psoriasis NEGATIVE: Solar erythema, sunburn Photo-sensitivity: photo-immunosuppression (solar herpes), photo-toxicity, photo-allergenicity, photo-dermatitis (lupus) Pigmentary diseases: spots, melasma (pregnancy) or vitiligo Skin aging Accelerator : deep wrinkles and loss of density and skin elasticity Photo-carcinogenesis (skin cancer) UV Radiations Photoaging Solar lentigines or age spots: irregular brown pigmented spots formed by UV exposure Solar elastosis: breakage induced by chronic UV exposure, the breakdown of collagen, elastin accumulation structure and loss of deep wrinkles cause dermal network Photoaging Photoaging L’Oréal publication New England Journal of Medicine Do you know your ABCDEs? A: ASYMMETRY B: BORDER C: COLOR D: DIAMETER E: EVOLVING •http://www.skincancer.org/es-ES/Los-ABCDEs-del-Melanoma Main Factors influencing the sunburn LATITUDE HEIGHT SEASONALITY 1. Intensity of the light DAY TIME EXPOSITION TIME TRANSMISSION REFLEXION 2. Skin Phototypes Fitzpatrick (1975) Skin Classification Behavior Hair & eyes Type Always burns, never Tends to have freckles, red or I very light, also "Nordic" tans blond hair, blue or green eyes. Usually burns, Tends to have light hair, II light, or light-skinned European sometimes tans blue/green or brown eyes. light intermediate, or dark- May burn, usually Tends to have brown hair and III skinned European or "average tans eyes. Caucasian" dark intermediate, also Sometimes burns, Tends to have dark brown eyes IV "Mediterranean" or "Olive" often tans. and hair. Moderate Often has dark brown eyes and V dark or "Brown" type constitutional hair. pigmentation Brown Marked constitutional VI very dark or "Black" type Black-brown eyes and hair. pigmentation Black Skin Phototypes and the reaction to the sun MED/UV-B, minutes PHOTOTYPE MED/UV-B, mJ/cm2 (*) I 15-30 8 II 25-35 18 III 30-50 28 IV 45-60 42 V 60-100 60 VI 100-200 (*) at 40ºN, summer time (M.A. PATHAK - 1983) MED= MINIMAL ERYTHEMA DOSE The Sun Protection Factor (SPF) - UVB SPF = Sun Protection Factor (only against UVB) (MED = Minimal Erythema Dose) UV Filter Classification ‣ Organic chemical compounds that absorb UV light ‣ Organic particles that mostly absorb UV light but also may reflect and scatter a fraction of light ‣ Inorganic particles that reflect, scatter and absorb UV light Organic UV Filters Classification: 1. PABA and p-aminobenzoates 2. Salicylates 3. Cinnamates 4. Benzophenones 5. Antranylates 6. Dybenzoylmethanes 7. Camphor Derivatives 8. Organic particulates 9. Others Organic UV Filters 1. PABA derivatives and p-aminobenzoates UVB OR C = O H N H 2-ethylhexyl dimethyl PABA (Padimate O) Organic UV Filters 2. Salicylates Benzyl salicylate UVB Ethylhexyl salicylate Homomenthyl salicylate OR’ Trietanolamine salicylate Potassium salicylate C O Amyl salicylate p-isopropylphenyl salicylate 4-isopropylbenzyl salicylate H O R Organic UV Filters 3. Cinnamates UVB C = O CH3 Ö CH = CH - OR 17 cinnamates, the most common ones: Ethylhexyl-p-methoxycinnamate (λmax: 310 nm) Isoamyl-p-methoxycinnamate Dietanolamine-p-methoxycinnamate Ethylhexyl-p-methoxycinnamate Organic UV Filters 4. Benzophenones Dioxybenzone (8) UVB-UVA Oxybenzone (3) Sulisobenzone (4) H Mexenone (10) O O = C RÖ Organic UV Filters 5. Antranilates (orto amino benzoates) UVA (λ max 336 nm) H N H O C O C10H19 Menthyl Antranilate Organic UV Filters 6. Dibenzoylmethanes UVA H O O O = = C C R1 R2 Butyl Methoxydibenzoylmethane (Avobenzone) λmax : 357nm Butyl Methoxydibenzoylmethane Enol Keto max 357nm max 260nm ENERGY RELEASE PATHWAYS Kochevar,I.E., Basic Principles of Photomedicine and Photochemistry Butyl Methoxydibenzoylmethane : photoestabilization 1. Octocrylene 2. Polysilicone-15 (Parsol®SLX) 3. Methylbenzylidene camphor 4. Bemotrizinol (Tinosorb® S) 5. Bisoctrizole (Tinosorb® M) 6. Butyloctyl Salicylate (HallBrite® BHB) 7. Hexadecyl Benzoate 8. Butyloctyl Benzoate 9. Undecylcrylene dimethicone (HallBrite® PSF) 10.Ecamsule (Mexoryl® SX) 11.Diethylhexyl Naphthalate (Corapan® TQ) 12.Diethylhexyl Syringylidene Malonate (Oxynex® ST) 13.Etc. Butyl Methoxydibenzoylmethane: other warnings 1. Solubility is key: octocrylene, ethylhexyl and homomenthyl salicylates, … to avoid crystal formation 2. Incompatible with metal ions: recommended the use EDTA 3. Avoid formaldehyde and donors: have a look at the preservative systems 3+ 4. Incompatible with TiO2 Al coated Organic UV Filters 7. Camphor Derivatives UVB 4-Methylbenzylidene camphor (Enzacamena) λmax : 302nm Other UV Filters Phenylbenzimidazole Sulfonic Acid (PBSA) UVB-WS λmax : 304nm Polysilicone –15 (Parsol® SLX) UVB • Dry touch silicone backbone • Liquid – no crystallization possible in formulation • Ideal for light and silky texture sunscreens • Improves sunscreen distribution and thus boosts SPF • Acts with water soluble PBSA in a synergistic way for highest UVB protection ® PARSOL SLX, proven synergy with PBSA to boost the SPF In vivo SPFs measured twice according to international SPF method (COLIPA) 36 Iscotrizinol or Diethyl Hexyl ButamidoTriazone (Uvasorb® HEB, DHBT) UVB N H O N H N N H N N N H O O O O Ethyl Hexyl Triazone (Uvinul® T150, EHT) UVB (λmax: 314 nm) O O N H N N H N N N H O O O O Diethylamino Hydroxybenzoyl Hexyl Benzoate (Uvinul® A Plus, DHHB) UVA O O O H O N Uvinul® A Plus B: Ethylhexyl methoxycinnamate & Diethylamino Hydroxybenzoyl Hexyl Benzoate Disodium Phenyl Dibenzimidazole Tetrasulfonate (Neo Heliopan® AP, DPDT) UVA-WS H O S S O H N N 3 3 N N H H S O N a S O N a 3 3 Terephthalilydene Dicamphor sulfonic acid (Mexoryl® SX) UVA-WS λmax: 338 nm O N a O S 3 S O N a 3 O Drometrizole Trisiloxane (Mexoryl® XL) Benzotriazole derivative UVB-UVA, λmax: 303 nm and 344 nm Organic particules Bemotrizinol o Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine (Tinosorb® S, BEMT) UVA/UVB (λmax: 310 and 340 nm) O C H 3 O H N N O H N O O Tinosornb ® S Aqua: Benzotrizinol in Polymethylmetacrylat, dispersed in water Bisoctrizole o Methylene Bis-Benzotriazolyl Tetramethylbutylphenol (Tinosorb® M, MBBT) UVA/UVB-WS (λ max: 360 nm) Absorption curves UVA range 1200 BEMT MBBT DHHB 1000 DPDT Avobenzone Benzophenone-3 800 600 E1/1 400 200 0 280 290 300 310 320 330 340 350 360 370 380 390 400 nm BEMT: Tinosorb S MBBT: Tinosorb M DHHB: Uvinul A+ DPDT: Neoheliopan AP Only 8 Organic UV filters approved worldwide INCI EU USA Japan Benzophenone-3 10% 6% 5%* Benzophenone-4 5% 10% 10%** Ethyl-Hexyl Methoxycinnamate 10% 7,5% 10%*** Phenylbenzimidazole sulfonic acid 4% 4% 3%§ Homosalate 10% 15% 10% Octyl Salicylate 5% 5% 10%§§ Octocrylene 10% 10% 10% Avobenzone 5% 3% 10%§§§ *5% in C&T, 0.02% eye lines;** 1% en C&T, 0.1% eye lines :*** 5% en C&T, 1% eye lines; § 7% en C&T,1% eye lines, §§ 1% en C&T, 0% eye lines §§§ 2% in C&T, 0.1% eye lines Inorganic UV Filters 1. Titanium dioxide 2. Zinc Oxide Coating 1 Rutile Coating 2 TiO2 Formulation Compatibility with ascorbyl palmitate •Comp 1 •Comp 2 •Comp 3 •control •Copm0 •Comp 4 •Comp 5 •Comp 6 • • • • • • • • Test protocol . 10% TiO2 and 10% ascoryl palmitate are added in diisobutyl sebacate . Optical evaluation (after 60 min) High SPF contribution: Performance impact by crystal size •UVB •UVA “Nano” - Cosmetic Regulation - Europe • Definition – Art. 2.1 (k) Regulation 1223/2009/EC ‘Nanomaterial’ means an insoluble or biopersistant and intentionally manufactured material with one or more external dimensions, or an internal structure, on the scale from 1 to 100 nm • Labeling obligation (Art. 19.1(g)(ii)) for cosmetics containing ingredients in nano- form: i.e. in the list of ingredients, the names of such substances shall be followed by the word 'nano' in brackets.