SC WATER-HANDLING PROPERTIES 293 STATISTICS Analysis of variance was used to compare treatment groups. Repeated measure statistics were used to evaluate the changes in the treatment sites over time. The paired com- parison t-test was used to evaluate the effects of treatment variables. To normalize the data for variations in skin condition along the forearm, the change from baseline was used in the paired comparison procedures (SigmaStat, Jandel Scientific). p 0.05 was considered statistically significant. RESULTS The biophysical data (mean, + SE) for all sites and time points are shown in Tables III, IV, and V. The changes and associated statistical significance are given in Table VI (p 0.05 was considered statistically significant). Figure 1 illustrates the changes in TEWL relative to the changes in MAT for the water soak. Figure 1 also shows the effect of NMF on TEWL and MAT for the soaked site 30 minutes after NMF application. The values in the figure have been normalized for changes in the parallel untreated control site. Relative to the initial skin condition, extraction of normal skin with 1:1 acetone/ether significantly increased TEWL but did not change MAT (Table VI) or baseline hydration (Table V). Exposure of normal skin to a fresh water soak significantly increased the TEWL at 15 minutes after the soak procedure. Thirty minutes later, the TEWL had decreased, presumably as a result of surface water evaporation. After four hours, TEWL had returned to the baseline value (Table VI). Soaking significantly decreased the MAT, a decrease that was sustained after four hours. Soaking significantly decreased the base- line hydration in the short term (15 min), but not after an additional thirty minutes. A/E Table III Summary of Effects of Skin Treatments on Transepidermal Water Loss (TEWL) Over Time Post-formula Post-formula Post- Post-soak application application Site Treatment Baseline extraction (15 min after) (30 min after) (4.5 hr after) 1 Untreated 9.8 + 2.5 9.8 + 2.0 8.1 + 1.9 9.5 + 2.8 2 Acetone/ether extraction 9.1 + 1.9 11.6 + 2.7 -- 8.5 + 1.7 10.4 + 1.9 3 Water soak 9.8 4- 2.0 11.2 4- 2.1 8.3 4- 2.2 9.6 + 2.1 4 A/E + soak 9.3 + 3.0 12.2 4- 4.3 12.5 + 2.7 9.4 + 2.5 10.5 4- 3.5 5 Untreated + vehicle 9.1 4- 2.4 -- -- 7.7 4- 2.2 8.7 4- 2.4 6 Untreated + NMF 8.9 4- 2.4 -- 6.9 -+ 2.3 7.9 4- 2.4 7 A/E + vehicle 8.7 + 1.9 10.9 4- 2.9 -- 8.4 4- 2.3 9.9 4- 2.2 8 A/E + NMF 9.1 + 2.2 10.9 + 3.2 -- 7.7 + 2.1 9.0 4- 2.3 9 Soak + vehicle 9.4 + 2.1 -- 10.7 4- 2.0 7.9 + 1.7 8.8 4- 1.8 10 Soak + NMF 9.0 + 1.6 -- 10.5 4- 2.0 6.5 + 1.7 7.7 4- 2.2 11 A/E + soak + vehicle 8.8 4- 2.5 11.0 4- 3.1 12.1 + 2.2 9.0 + 2.2 10.2 + 2.5 12 A/E + soak + NMF 9.1 + 2.5 14.8 + 7.1 12.2 + 2.3 8.0 4- 2.4 9.2 4- 2.9 TEWL (g/m2/hr) was measured for each site prior to any treatment or application procedure (baseline reading), following the A/E extraction, 15 minutes after the water soak, 30 minutes after NMF application, and 4.5 hours following NMF treatment. The values are mean + SEM, n = 11. A/E indicates acetone/ether extraction, soak indicates water soak, and vehicle indicates the hydroxyethyl cellulose-containing control for the NMF formulation.

294 JOURNAL OF COSMETIC SCIENCE Table IV Summary of Effects of Skin Treatments on Rate of Moisture Accumulation (MAT) Over Time Site Post-formula Post-formula Post- Post-soak application application Treatment Baseline extraction (15 min after) (30 min after) (4.5 hr after) 1 Untreated 1.6 + 1.5 -- 0.8 + 0.5 1.3 ñ 1.2 1.3 + 1.0 2 Acetone/ether extraction 1.1 ñ 0.8 1.2 _+ 0.9 -- 1.1 + 0.8 1.2 ñ 0.8 3 Water soak 1.1 + 1.0 -- 0.5 ñ 0.5 0.5 ñ 0.3 0.7 ñ 0.7 4 A/E + soak 1.1 ñ 0.8 1.0 ñ 0.9 0.3 ñ 0.3 0.4 ñ 0.3 0.5 ñ 0.4 5 Untreated + vehicle 1.4 ñ 1.4 -- -- 0.8 ñ 0.7 1.3 _+ 1.3 6 Untreated + NMF 1.4 ñ 1.1 -- -- 2.6 ñ 2.0 1.5 ñ 1.3 7 A/E + vehicle 0.9 -+ 0.6 0.9 ñ 0.6 -- 0.7 ñ 0.4 1.0 + 0.8 8 A/E + NMF 1.0 ñ 1.3 1.1 _+ 1.1 -- 1.9 ñ 1.2 1.4 + 1.3 9 Soak + vehicle 1.0 + 0.5 -- 0.5 + 0.3 0.6 _+ 0.3 0.5 ñ 0.2 10 Soak + NMF 1.4 + 1.0 -- 0.6 ñ 0.3 1.7 ñ 1.1 0.7 ñ 0.4 11 A/E + soak + vehicle 1.0 ñ 1.0 1.6 _+ 1.5 0.3 ñ 0.1 0.4 ñ 0.3 0.6 + 0.4 12 A/E + soak + NMF 1.0 + 0.9 1.4 + 1.2 0.2 _+ 0.2 1.5 _+ 1.3 0.9 ñ 0.5 The rate of moisture accumulation (MAT) (cru/sec) was measured for each site prior to any treatment or application procedure (baseline reading), following the A/E extraction, 15 minutes after the water soak, 30 minutes after NMF application, and 4.5 hours following NMF treatment. The values are reported as slope of the regression line and are mean ñ SEM, n = 11. (For abbreviations, see footnote to Table III.) Table V Summary of Effects of Skin Treatments on Baseline Hydration at Various Times Post-formula Post-formula Post- Post-soak application application Site Treatment Baseline extraction (15 rain after) (30 min after) (4.5 hr after) 1 Untreated 12.7 ñ 3.5 -- 9.25 + 2.1 10.7 _+ 3.0 12.3 ñ 3.0 2 Acetone/ether extraction 10.6 ñ 2.1 14.5 ñ 2.1 -- 13.7 + 3.0 11.3 + 2.6 3 Water soak 10.4 ñ 3.0 -- 6.4 + 1.4 7.2 -+ 1.5 6.1 ñ 1.8 4 A/E + soak 10.8 ñ 3.1 11.7 ñ 2.9 4.2 + 1.4 5.1 + 1.5 4.3 + 1.0 5 Untreated + vehicle 10.7 ñ 2.7 -- 12.6 + 2.9 12.0 ñ 3.9 6 Untreated + NMF 12.4 ñ 2.6 -- -- 21.8 + 5.9 12.7 + 3.9 7 A/E + vehicle 10.0 ñ 1.5 13.8 + 1.9 -- 11.5 + 3.4 9.1 + 1.6 8 A/E + NMF 12.4 ñ 2.1 15.7 ñ 4.0 -- 19.9 + 4.7 12.8 ñ 2.5 9 Soak + vehicle 9.9 ñ 1.6 -- 5.78 ñ 1.2 7.3 + 1.9 8.33 + 2.2 10 Soak + NMF 13.4 ñ 2.4 -- 6.78 ñ 1.0 15.1 ñ 2.6 9.3 ñ 1.7 11 A/E + soak + vehicle 13.2 ñ 2.3 16.3 ñ 3.6 3.7 + 1.0 6.0 + 1.0 5.8 ñ 1.5 12 A/E + soak + NMF 12.2 ñ 3.5 10.6 ñ 2.8 7.3 ñ 1.5 16.6 ñ 5.9 9.9 -+ 3.2 The skin hydration (cru) was measured for each site prior to any treatment or application procedure (baseline reading), following the A/E extraction, 15 minutes after the water soak, 30 minutes after NMF application, and 4.5 hours following NMF treatment. The values are mean ñ SEM, n = 11. (For abbreviations, see footnote to Table III.) extraction followed by a water soak resulted in TEWL, MAT, and baseline hydration profiles similar to those of the individual A/E and soak treatments (Table VI). Application of the NMF resulted in significantly lower TEWL for the untreated control, the A/E extracted site, and the water-soaked site after thirty minutes (Table VI). The TEWL was directionally lower 30 minutes after NMF treatment for the A/E-plus- water-soak site. The significant decrease in TEWL for the A/E site and the directional