Table I Characteristics and Maximum Authorized Concentrations of UV Filters in the Present Study UV fi lter USAN name Abbreviation CAS # Molecular formula Molecular weight Max. authorized concentration (%) 1 Drometrizole Drometrizole DT 2440-22-4 C13H11NO3 225.25 —2 Benzophenone-8 Dioxybenzone BZ-8 131-53-3 C114H12O4 244.24 3% 4-Methylbenzylidene camphor Enzacamene MBC 36861-47-9 C18H 22 O 254.37 4% p-Aminobenzoic acid Aminobenzoic acid PABA 150-13-0 C7H7NO2 137.14 5% Butyl methoxydibenzoylmethane Avobenzone BMDM 70356-09-1 C20H22O3 310.38 5% Ethylhexyl triazone Octyl triazone EHT 88122-99-0 C48H66N6O6 823.07 5% Menthyl anthranilate Menthyl anthranilate MA 134-09-8 C17H25NO2 275.39 5% Ethylhexyl dimethyl p-aminobenzoic acid Padimate O ED-PABA 21245-02-3 C17H27NO2 277.40 8% 2-Phenylbenzimidazole-5-sulfonic acid Ensulizole PBS 27503-81-7 C13H10N2OS3 274.30 8% Benzophenone-3 Oxybenzone BZ-3 205-031-5 C14H12O3 228.25 10% Diethylhexyl butamidotriazone Iscotrizinol DBT 154702-15-5 C44H59N7O5 765.98 10% Ethylhexyl methoxycinnamate Octinoxate EMC 5466-77-3 C18H26O3 290.40 10% Isoamyl p-methoxycinnamate Amiloxate IMC 71617-10-2 C15H20O3 248.32 10% Methylene bis-benzotriazolyl tetramethylbutylphenol Bisoctrizole MBBT 103597-45-1 C41H50N6O2 658.88 10% Octocrylene Octocrylene OC 6197-30-4 C24H27NO2 361.48 10% Terephthalylidene dicamphor sulfonic acid Ecamsule TDS 92761-26-7 C28H34O8S2 562.69 10% 1 Maximum authorized concentration of UV fi lters is listed in Directive 76/768/EEC and in Notifi cation No. 2009-52 of the Korea Food and Drug Administration. 2 Maximum authorized concentration of Drometrizole is 7% in Korea. MONITORING OF UV FILTERS BY HPLC 105

JOURNAL OF COSMETIC SCIENCE 106 Figure 1. Structures of 16 UV fi lters: (1) PABA (2) 2-Phenylbenzimidazole-5-sulfonic acid (3) Tere- phthalylidene dicamphor sulfonic acid (4) Benzophenone-8 (5) Benzophenone-3 (6) Isoamyl p-methoxycin- namate (7) Drometrizole (8) 4-Methylbenzylidene camphor (9) Octocrylene (10) Menthyl anthranilate (11) Ethylhexyl dimethyl PABA (12) Butyl methoxydibenzoylmethane (13) Ethylhexyl methoxycinnamate (14) Diethylhexyl butamidotriazone (15) Ethylhexyl triazone (16) Methylene bis-benzotriazolyl tetrameth- ylbutylphenol.