TWO TESTS OF DETERGENT IRRITANCY 145 +1 +1 +1 +1 +1

146 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table II Stratum Corneum Capacitance (arbitrary units) as Measured Before and at Different Time Intervals in the Patch Test Procedure and the Hand/Forearm Immersion Procedure, Respectively Patch test Immersion test Time Water N28 ASV Plantaren Water N28 ASV Plantaren 0 64+8 64+9 66_+9 65+9 68+6 70+7 68+5 68+6 1 58 + 10 60+ 11 55 +8 53 +6 73 +7 66+ 5 68+6 73-+7 2 59+7 61+ 10 55 + 13 49+6 71-+8 67 +9 68+7 71+9 3 62 +7 57 + 11 61+ 10 56-+ 5 65 +5 59+9 63 +9 65 + 5 4 64+5 35 + 15 54+8 53-+ 11 69+5 65 +5 69+6 69+ 5 MANOVA s. s. s. s. n.s. n.s. HAND/FOREARM IMMERSION TEST Besides differences in baseline values, similar kinetics were obtained when comparing the reactions on the hand with those on the forearm. As a consequence, we will only discuss the results measured on the forearm. Compared to the patch test, the irritation response was less pronounced in the hand/forearm immersion test. The TEWL values, as measured during and after the immersion protocol, showed a trend to increase as a function of the number of immersions (see Table I). This trend was noticed for the different detergent solutions. A weak increase in function of the number of immersions was equally noticed for the immersion in water alone. For the immersion in water alone, a return to baseline values was noticed within 24 hours after the last immersion. Statistically, no differences were detected between the different kinetics. When analyzing the global response (YWEWL), only a weak increase was detected after immersion in the different detergent solutions compared to immersion in water alone (see Table IV). Hydration kinetics showed a more pronounced decrease after immersion in the N28 solution compared to ASV and Plantaren solution (see Table II). Lowest values were measured eight hours after the third immersion. The kinetics of the N28 was found to be significantly lower compared to immersion in water alone. The decrease caused by the other products was not statistically significant. Table III a* Skin Color (arbitrary units) Value as Measured Before and at Different Time Intervals in the Patch Test Procedure and the Hand/Forearm Immersion Procedure, Respectively Patch test Immersion test Time Water N28 ASV Plantaren Water N28 ASV Plantaren 0 6.3 + 1.5 6.1+ 1.4 6.0+ 1.4 6.2 + 1.3 6.1+ 1.2 6.5 + 1.4 6.3 + 1.5 6.3+ 1.4 1 7.7 + 1.2 9.3 + 1.5 8.1 _+ 1.6 8.7 + 1.3 6.5 + 1.4 6.6 + 1.4 6.5 + 1.3 6.5 + 1.5 2 7.4 _+ 1.6 11.1 + 3.2 9.0 + 1.9 8.6 + 1.7 6.6 + 1.6 6.8 _+ 1.2 6.6 + 1.2 6.8 + 1.7 3 7.3 + 1.2 12.6 + 1.6 10.0 + 2.0 8.8 + 1.1 6.8 + 1.4 6.9 + 1.6 6.7 -+ 1.2 7.1 _+ 1.5 4 7.1 + 1.4 11.1 + 1.6 8.9 + 1.5 8.2 _+ 1.2 6.7 + 1.1 6.7 + 1.1 6.8 + 1.1 6.8 + 1.2 MANOVA s. s. s. n.s. n.s. n.s.