MICROBIAL-CONTAMINATION AND PRESERVATIVE EFFICACY OF TOPICAL CREAMS

Nineteen different brands of topical creams were tested in duplicate f or microbial growth. The efficacy of their preservation was assessed, when possible, by standard pharmacopoeial procedures. Microbial growth was demonstrated in cultures from all specimens. However, high counts (> 10(4) c.f.u./g) were obtained from eight specimens from six differ ent brands. The microbes were found to belong to different species of bacteria and fungi including Pseudomonas aeruginosa. Two samples of ea ch of the seven, easily emulsifiable creams, were challenged with stan dard strains of Staphylococcus aureus, Escherichia coli, Pseudomonas a eruginosa and Candida albicans to assess the efficacy of the preservat ives used in their preparations. With the exception of a single brand, all creams tested were ineffectively preserved. This study highlights the dangers of marketing domestically prepared topical creams and mor e effective monitoring of the components for all topical creams is rec ommended. The inclusion of a proper preservative system in these formu las is essential.