JOURNAL OF COSMETIC SCIENCE 148 (42) T. Coenye , P. Vandamme, J. R. Govan, and J. J. LiPuma, Taxonomy and identifi cation of the Burkhold- eria cepacia complex, J. Clin. Microbiol., 39, 3427–3436 (2001). (43) G. Zhou, Q . Shi, Y. Ouyang, and Y. B. Chen, Involvement of outer membrane proteins and peroxide- sensor genes in Burkholderia cepacia resistance to isothiazolone, World J. Microbiol. Biotechnol., 30, 1251– 1260 (2014). (44) K. A. Rho d es and H. P. Schweizer, Antibiotic resistance in Burkholderia species, Drug Resist. Updates, 28, 82–90 (2016). (45) V. Gautam , P. P. Patil, S. Kumar, S. Midha, M. Kaur, S. Kaur, M. Singh, S. Mali, J. Shastri, A. Arora, P. Ray, and P. B. Patil, Multilocus sequence analysis reveals high genetic diversity in clinical isolates of Burkholderia cepacia complex from India, Sci. Rep., 6, 35769 (2016). (46) A. Balwin , A. Mahenthiralingam, P. Drevinek, P. Vandamme, J. Govan, and D. Waine, Environmental Burkholderia cepacia complex isolates in human infections, Emerg. Infect. Dis., 13, 458–461 (2007).

J. Cosmet. Sci., 71, 149–165 (May/June 2020) 149 Effect of Solvents on the In Vitro Sun Protection Factor and Broad-Spectrum Protection of Three Organic UV Filters MARIAM ABOU-DAHECH, ALLISON SCHAEFER, LAURA LAM-PHAURE, AN HUYNH, MARK CHANDLER, and GABRIELLA BAKI , Department of Pharmacy Practice, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614 (M.A., A.S., L.L.-P., A.H.,G.B.), ACT Solutions Corp, Newark, DE 19713 (M.C.) Accepted for publication February 28, 2020. Synopsis Solvents play an essential role in the performance of ultraviolet (UV) fi lters. The goal of this study was to understand how the in vitro sun protection factor (SPF) and broad-spectrum protection of three organic UV fi lters (homosalate, ethylhexyl salicylate, and butyl methoxydibenzoylmethane) and a combination of these are infl uenced by solvents. Twenty-four solvents were selected based on the ingredient active gap for testing. Mixtures of UV fi lters and solvents were formulated, and in vitro SPF, wavelength of maximum absorbance, broad-spectrum protection, and spreadability were evaluated. Results indicate that in vitro SPF of organic sunscreens can be signifi cantly enhanced by solvents. Relying on solubility data only was not found to be a good approach in this study. The most effi cient solvents shared multiple similar structural characteristics, including ester bonds, conjugated structure, aromatic rings, and –CN groups however, the absence of some of these structural elements did not necessarily prevent a solvent from being a booster. The wavelength of maximum absorbance was signifi cantly shifted in the UVA range by most solvents, whereas minimal or no shift was observed in the UVB range. Results of this study provide practical information that can guide sunscreen formulators in selecting solvents for UV fi lters and making more effective sunscreens. INTRODUCTION Ultraviolet (UV) radiation has a variety of biological and clinical effects on the skin rang- ing from erythema to pigmentation (1) to premature aging (2) and skin cancer. A com- mon approach to prevent the damaging effects of UV radiation on the skin is to reduce intentional exposure to UV radiation and use sunscreens. Recent legislations in Hawaii Address all correspondence to Gabriella Baki at Gabriella.Baki@utoledo.edu. Part of the work was presented as poster presentations at the following meetings: Michigan Society of Cos- metic Chemists Fall Symposium, Grand Rapids, MI, on September 6, 2018 New York Society of Cosmetic Chemists Meeting, Totowa, NJ, on March 13, 2019 American Chemical Society Central Regional Meeting in Midland, MI, on June 4–8, 2019 and Midwest Society of Cosmetic Chemists Fall Technical Symposium, Chicago, IL, on October 8, 2019.