160 JOURNAL OF COSMETIC SCIENCE subjects (50%), moderate in eight subjects (33.3%), and severe in three subjects (12.5%). AH subjects tested reported stinging/burning with 70% isopropyl alcohol. The responses were mild in three subjects (12.5%), moderate in eleven subjects (45.8%), and severe in ten subjects (41.7%) (Figure 1). Comparisons of mean stinging/burning scores between treatments using the Wilcoxon signed-rank test indicated that the Bactine® prototype wipes with a cellulose base induced significantly less stinging/burning than both sting/burn controls (70% isopro­ pyl alcohol and 3% hydrogen peroxide). Hydrogen peroxide also induced significantly less stinging/burning than isopropyl alcohol. No significant differences, instead, were found between Bactine® prototype wipes and the no-sting/no-burn control (0.9% so­ dium chloride) (Table I). Analysis of variance testing for possible order (treatment sequence) effects with the prototype wipes versus alcohol and hydrogen peroxide indi­ cated no significant differences due to order or period effects. Significant treatment effects were, instead, detected between the prototype wipes and both 70% isopropyl alcohol and 3% hydrogen peroxide. DISCUSSION Burning and stinging is often elicited with the application of antiseptic-anesthetic first-aid formulations to minor cuts and scrapes. In this investigation, we wanted to test the hypothesis that a new prototype antiseptic-anesthetic wipe did not induce significant 20 D prototype wipe 18 0.9% sodium chloride .,, 16 ■ 3% hydrogen peroxide 14 ■ 70% isopropyl alcohol GI 12 :I .,, 10 II 0 z ... 8 GI 6 E :I 4 2 0 None Mild Moderate Severe Intensity of responses Figure 1. Number of subjects experiencing stinging/burning sensation during application, and distribu­ tion of the intensity of responses. The majority of subjects did not experience any burning or stinging with the Bactine® prototype wipe or with saline. Hydrogen peroxide and, especially, isopropyl alcohol induced a higher incidence of severe responses.

LACK OF BURNING/STINGING FROM FIRST-AID WIPES 161 Table I Summary of Analysis Results for Burning/Stinging (n = 24) Comparisons Mean SD *P value Bactine® wipe 0.25 0.44 0.5000 Sodium chloride 0.9% 0.29 0.46 Bactine® wipe 0.25 0.44 0.0001 Isopropyl alcohol 70% 2.29 0.69 Bactine® wipe 0.25 0.44 0.0001 Hydrogen peroxide 3% 1.54 0.78 Hydrogen peroxide 3% 1.54 0.78 0.0018 Isopropyl alcohol 70% 2.29 0.69 SD = standard deviation. Scoring scale: 0 = none, 1 = mild, 2 = moderate, 3 = severe. * The Wilcoxon signed-rank test was performed to analyze differences. burning or stinging on superficial wounds. In order to evaluate these sensory responses, we selected the tape-stripping method as a means to achieving uniform superficial wounds without the risk of scarring. With this technique, the depth of the wound can be controlled. As layers of corneocytes are removed by tape, it becomes progressively more difficult to detach corneocytes (7) because of stronger intercellular desmosomal interconnections in the deeper layers. The amount of stratum corneum removed by each stripping depends, therefore, on the adhesion of the tape to the skin layer and on the cohesiveness between corneocytes. In this study, the target depth of wounding was reached with the visualization of the glistening layer and with a barrier damage of 30-70 g/m2/h by evaporimetry. This value corresponds to an increase in TEWL of more than three times the average baseline TEWL of 5.4 g/m2/h (standard deviation of 2.1). We reached the TEWL target after approximately 30-50 strippings, depending on the stratum corneum's thickness and looseness in each subject. We used Transpore® tape because it was shown to create a significant increase in TEWL (30.8 g/m2/h) after 40 tape strippings and to perform significantly better than Micropore® rayon tape (7). We tested the two positive controls on Webril® cotton pads to simulate the consumer use of these formulations. In a previous unpublished pilot study using the same wound model, we applied all formulations, including saline and 70% isopropyl alcohol, to Webril® cotton pads. In that investigation, two out of 24 subjects (8.33%) reported a mild stinging/burning from the saline control. This represents a slightly lower incidence of responses than in the current study, suggesting that the Webril® pad used for the positive controls does not potentiate the stinging and burning of the formulations. The results demonstrate the lack of significant burning and stinging from the prototype pramoxine HCL/benzalkonium chloride wipe on superficial wounds. The majority of the subjects did not perceive any stinging or burning with this formulation and the inci­ dence of mild responses was lower than the one for the saline control. On the contrary, the 100% incidence of burning and stinging responses to 70% isopropyl alcohol, with the majority in the moderate-to-severe category, supports the adequacy of the method used and of the wound depth for the sensory assessment of topicals on superficial