PRESERVATIVE EFFICACY TESTING 5 FORI•JL• 1 10 20 30 40 50 FORMULA 3 8 7 .•5 3 1 0 0 10 20 30 40 50 HOURS •5 0 10 20 30 40 50 •LA7 8• 7 • •2• o 10 20 3o 40 50 HOURS FORMULA 2 8 5 0 10 20 30 40 50 HOURS •4 5 1 o 10 20 30 40 50 FORNU.A 6 7 •4 2 1 0 0 10 20 30 40 50 8' •8 o lO •o 3o •o FORMULA 9 ß Shewanella putrefacien.• ß Burkholderia cepacia & Escherichia coti x Staphylococcus aureus ß Bacillus sp. 0 10 20 30 40 50 HOURS Figure 1. Survivor curves of the rates of inactivation of S. putrefaciens, B. cepacia, E. co/i, S. aureus, and Bacillus sp. in nine formulations, one without preservative (formula 1) and eight with different preservative systems (formulas 2, 3, 4, 5, 6, 7, 8, 9).

6 JOURNAL OF COSMETIC SCIENCE Table II Number of Surviving Microorganisms (CFU/g) in Periods of Time Specified by Official Methods for One Cosmetic Formulation Without Preservative and Eight Others With Different Preservative Systems Time Formula Organism 0 48 h 7 d 14 d 21 d 28 d S. putrefaciens B. cepacia E. coli S. aureus Bacillus sp. S, putrefaciens B. cepacza E. coli S, aureus Bacillus sp. S, putrefaciens B, cepacza E. coli S. aureu. g Bacillus sp. S. putrefaciens B, cepacza E. coli S. aureus Bacillus sp. S. putrefaciens B. cepacza E. coli S. aureus Bacillus sp. S. putrefaciens B. cepacza E. coli S. aureus Bacillus sp. S. putrefaciem B, cepacza E. coli S. aureus Bacillus sp. S. putrefaciens B. cepacza E. coli S. aureus Bacillus sp. S. putrefaciens B. cepacza E. coli S. aureu$ Bacillus sp. 4.2 x 10 6 2.0 x 10 6 3.2 x 10 6 4.50 x 105 2.20 x 10 4 1.70 x 10 2 4.0 x 106 7.4 x 106 1.77 x 106 2.20 x 105 5.7 x 104 2.2 x 10 2 3.4 x 106 5.5 x 106 2.32 x 106 1.00 X 10 4 2.50 X 103 3.00 X 102 1.31 X 107 9.6 X 106 1.00 X 107 5.4 X 105 4.0 X 103 10 1.08 X 106 6.2 X 103 3.5 X 103 4.2 X 103 5.0X 102 3.80X 102 3.5 x 10 6 10 10 10 10 10 4.7 x 106 5.6 x 103 10 10 10 10 6.0 x 10 6 10 10 10 10 10 1.17 x 10 7 1.02 x 103 30 10 10 10 1.9 x 10 6 4.7 x 10 3 3.4 x 103 3.8 x 10 3 2.50 x 10 2 2.80 x 10 2 2.93 x 106 5.10x 103 10 10 10 10 4.8 x 106 4.4 x 105 3.5 x 104 4.2 x 103 6.2 x 102 10 1.32 x 107 9.5 x 104 30 10 10 10 2.80 x 107 3.0 x 103 10 10 10 10 1.02 x 106 7.1 x 103 4.4 x 103 1.3 x 102 1.10 x 102 1.50 x 102 7.0 x 10 6 10 10 10 10 10 4.3 x 10 6 1.38 x 105 2.10 x 10 2 10 10 10 3.73 x 107 8.6 x 102 10 10 10 10 1.57 x 107 10 10 10 10 10 1.09x 106 4.7 x 103 4.9x 103 5.2 x 103 2.30x 102 2.10x 102 1.11 x 107 10 10 10 10 10 6.4 x 10 6 1.19 x 105 5.6 x 10 4 3.2 x 10 4 2.30 x 103 1.10 x 10 2 8.6 x 10 6 8.7 x 10 • 10 10 10 10 9.7 x 106 10 10 10 10 10 1.58 x 106 4.5 x 103 3.1 x 103 4.5 x 102 3.8 x 102 2.20 x 102 3.9x 106 10 10 10 10 10 7.8 x 106 9.8 x 103 6.4 x 103 3.4 x 102 10 10 1.24 x 107 10 10 10 10 10 7.8 x 106 10 10 10 10 10 3.0 x 106 4.2 x 103 6.5 x 103 1.90 x 103 5.4 x 102 3.9 x 102 2.32 x 106 10 10 10 10 10 3.4 x 106 4.3 x 105 10 10 10 10 9.6 x 106 10 10 10 10 10 2.93 x 107 40 10 10 10 10 2.30 x 105 4.1 x 103 4.3 x 103 4.5 x 10 2 3.4 x 10 2 2.50 x 10 2 3.0 x 106 10 10 10 10 10 3.0 x 106 10 10 10 10 10 5.3 x 10 6 10 10 10 10 10 1.02 x 106 10 10 10 10 10 2.90 x 105 1.1 x 103 5.2 x 103 6.2 x 103 4.6 x 102 2.10 x 10 2 6.6 x 105 10 10 10 10 10 3.8 x 10 6 10 10 10 10 10 9.8 x 10 6 10 10 10 10 10 9.9 x 106 10 10 10 10 10 1.12 x 105 8.4 x 103 6.1 x 103 6.5 x 103 4.3 x 102 3.3 x 10 2