756 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS after application are only slightly lower than obtained with the solutions but are marked after this point. After two hours, the count had risen to about 25% of the initial reading 100 9O 8O 7O (• 60 o 540-- 3o I 2 3 4 5 Time in hours Figure 7.--Face Plate Counts--Laboratory prepared test solutions. and after four hours to between 40 and 55%. At six hours, the count is about 35% lower than that obtained without perfumes. When a germicide, such as hexachlorophene, is added to the solutions, the results are even more dramatic. Figure 8 shows an almost complete kill of

EFFECTS OF AFTER-SHAVE LOTIONS ON SKIN FLORA 757 the skin flora immediately after application. h•hibition is very evident at the two, four and six hour marks, rising to only 25% of the original count at the end of the test period. Although solution//6, the only one of this group which contains perfume, shows greater inhibition than the others, the difference is not significant, and these lotions should be considered as having equal effects. Commercial after-shave lotions present a varied picture, as shown in 40.-- 30-- •o i 2 3 4 5 6 Time in hours Figure 8.--Face Plate Counts--Test solutions with addition of hexachlorophene. Fig. 9. In the main, they follow the in vitro test results, with Lotion "B," the most effective, once again having the greatest activity. Lotions "A" and "E" which gave similar results in the serial dilution and zone of inhibi- tion tests showed a divergence at the conclusion of the test at six hours. On the other hand, Lotion "C," which was significantly more active than Lotion "D" in the in vitro testing, produced approximately the same effect on the skin. Figure 10 summarizes the in vivo results obtained with the various lotions and solutions. The effect of the addition of perfumes and antimicrobial agents to after-shave lotions can be clearly seen. The upper curve repre- sents the solutions without perfume. The skin flora has returned to the pre-application level after six hours. The center curve, combining commer- cial lotions and solutions with perfume, shows a continued inhibition or reduction of skin flora after six hours at a level 40% below the non-perfume