HYDRATION AND SPF TESTING OF LIP BALM FORMULATIONS 5 participants exhibited lip dryness of grade 3 or 4 (16). The participants then underwent a dry-down period of 3–7 days during which the use of moisturizing products on their lips was prohibited. This was followed by a baseline visit and fi ve assessment visits over an 11-d period (days 3, 5, 8, 10, and 12). The participants applied test product B six times daily between the fi ve assessment visits. SPF determination studies. In studies RH01927 and RH01928, four test sites were selected on each participant’s back and randomized to one of four treatments: two sites were un- treated negative controls, the SPF standard P2 positive control was applied to a third test site, and test product A was applied to the fourth test site. Study investigators were blinded to the treatment allocation for each of the test sites. The four test sites were each divided into six subsites for UV irradiation. Participants at- tended the study clinic on three consecutive days. At visit 1, all six subsites of one un- treated control test site were exposed to UV light. Irradiated sites were visually assessed at visit 2 using the erythema grading criteria (Table I) (17) to detect the minimal erythe- mal dose (MED) of the unprotected site (MEDu). Treatment application (where appropriate) and UV irradiation at the remaining untreated control test site and two treatment test sites were conducted at visit 2. Test product A and the SPF standard P2 positive control were applied using a fi nger cot and allowed to dry for ≥15 min before UV irradiation. At visit 3, the effect of UV irradiation on the various test sites was assessed using the erythema grading criteria and the MED determined for test product A. In study RH02117, fi ve test sites were selected on each participant’s back and randomized to one of fi ve treatments: two sites were untreated negative controls, the SPF standard P2 positive control was applied to a third test site, and test products B and C were applied to a fourth and fi fth test site, respectively. Study investigators were blinded to the treat- ment allocation for each of the test sites. Each test site was divided into fi ve subsites before UV irradiation. The participants attended the study clinic on three consecutive days. At visit 1, all fi ve subsites of one untreated control test site were exposed to UV light, using a Xenon Arc Solar Simulator2 (150 W) (Solar Light Co., Inc., Philadelphia, PA). Irradiated sites were visually assessed at visit 2 using the erythema grading criteria (Table I) (17) to determine MEDu. Treatment application and UV irradiation at the remaining four test sites were conducted at visit 2. Test products B and C and the SPF standard P2 positive control were applied using a fi nger cot and allowed to dry for 30 min before UV irradiation. At visit 3, the effect of UV irradiation on the various test sites was assessed using the erythema grad- ing criteria, and the MED was determined for test product B and test product C. Table I Erythema Grading and Defi nitions (17) Grade Defi nition 0 No reaction 1 Minimal or doubtful erythema, barely perceptible compared with the surrounding 2 Mild, but defi nite erythema with clearly defi ned borders 3 Moderate erythema 4 Marked/severe erythema

JOURNAL OF COSMETIC SCIENCE 6 In study RH02385, four test sites were selected on each participant’s back and random- ized to one of four treatments: one site was an untreated negative control, the SPF stan- dard P2 positive control was applied to a second test site, and test products D and E were applied to the third and fourth test sites, respectively. The study investigators were blinded to the treatment allocation for each of the test sites. Each test site was divided into six subsites for UV irradiation. The participants attended the study clinic on 4 d. At visit 1, all six subsites of the untreated control site were exposed to UV light, using a 300 W Xenon arc lamp (Solar Light Co., Inc., Philadelphia, PA). Irradiated sites were visually assessed at visit 2, the day after visit 1, using the erythema grading criteria (Table I) (17) to determine MEDu. Treatment application and UV irradiation at the remaining three test sites were conducted at visit 3, within a week of visit 1. Test products D and E and the SPF standard P2 positive control were applied using a fi nger cot and allowed to dry for 15–30 min before UV irradiation. At visit 4, within 16–24 h of visit 3, the effect of the UV irradiation on the various test sites was assessed using the erythema grading criteria and the MED determined for test product D and test product E. STUDY ASSESSMENTS Barrier function and moisturizing abilities study. In phase 1 of study RH02116, the effect of a new lip balm formulation and four comparator lip balm products on barrier function was determined using TEWL, assessed using a cyberDERM RG1 evaporimeter, as a mea- sure of barrier function in a dry-skin leg model. The moisturizing abilities of the fi ve lip balm formulations were also assessed in the dry-skin leg model, using visual assessment, Skicon, and Corneometer methods. Baseline barrier function and skin hydration were as- sessed before a single application of each lip balm, and at 1, 3, and 6 h postapplication. In phase 2 of study RH02116, TEWL, DMM, Corneometer, and visual assessment were used to measure changes in the moisture content of the lips after application of test product B. Visual assessment of lip dryness was carried out by a trained evaluator: 0 was categorized as no dryness and 4 was categorized as severe scaling with severe fi ssuring or cracking. Test product B was applied six times daily by the participants over an 11-d period. SPF determination studies. For the SPF studies, the MED for each participant was determined for an unprotected test site (MEDu) as a negative control, a site treated with the test product (tpMEDp), and a test site treated with the SPF standard control product (ssMEDp). MED is defi ned as the smallest UV dose that produces perceptible redness of the skin with clearly defi ned borders 20–24 h after UV irradiation using erythema grading crite- ria (17) (Table I). A series of six UV doses increasing by increments of 25% were admin- istered to the six test subsites of the untreated site. A series of six UV doses increasing by increments of 20% were administered to the six test subsites of the sites treated with test products or the P2 control. In all UV dose series, the middle dose administered was equiv- alent to MEDu multiplied by the expected SPF of the test product on untreated skin. Exposure time was infl uenced by the participant’s skin phototype and the power of the solar simulator. MED was measured through visual observation of the test site immedi- ately after irradiation and 16–24 h postirradiation. In study RH02385, the mean ITA of six repetitive chroma meter measurements was calculated to categorize the skin color and skin type of each participant (15).