8O4 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS preservation system. It is the author's view that the preservation ability of a product should be well in excess of the minimum necessary to inhibit the anticipated flora, and ideally one aims at a product that is self-sterilizing. In the author's experience, a self-sterilizing preparation can be achieved in most cosmetic and pharmaceutical products, without any significant increase in cost or loss of marketability. Sanitation Preservation should not be expected to compensate for insanitary or careless manufacturing or packaging. Aseptic production, with the ex- ception of eye preparations, is neither economical nor necessary. The product will therefore be microbiologically challenged, the magnitude and quality of which will vary with the ingredients, water supply, cleanli- ness, and season. This challenge may be most severe for it is here that continuing adaptation of the pseudomonads to the formulations takes place. The number of organisms from these sources has a bearing on their subsequent ability to proliferate within the preparation. Very small inocula have little opportunity to multiply. Large inocula in- crease the assault on the preservation system and increase the prob- ability that adaptive resistant pseudomonads will be introduced into the product. Ingredients themselves can be a potent source of contamination. In time the troublemakers are found, and microbial specifications are then added to future purchase contracts. Anionic detergents have frequently been a particular problem. Containers are rarely a problem but closures are. A liner may support growth or, by absorbing moisture from spat- terings of the product on the surface, alter the potency of the preserva- tives. Pseudomonads with borderline resistance can develop there, and once enhanced, infect and multiply within the preparation itself. Water supply is a particularly important source of Pseudomonas. The difficulty of eradicating this organism from water is underscored by the work of Belium and Koshi (25), who found that the resistance of Pseudomonas to chlorine ranged from 45-150 ppm. Water supply sys- tems should be monitored microbiologically, from the main to the manu- facturing tank inlet. Attention should be paid to the state of pipe work, valves, hoses, loops, and other sites of water stagnation. The water supply often contains a small number of organisms but without adequate control, water can issue from a tap or hose with thousands of pseudomo- nads and other gram-negatives/mi. A demineralizer may be a frequent source of this development. it provides a good medium for multiplica-

PSEUDOMONADS IN COSMETICS 80• tion and during warm weather can discharge counts of 100,000 or more gram-negatives. The best water control system the author has devised has been the installation of a hot water storage tank and manufacturing processes have been revised to use hot water wherever possible. The manufacturer must take steps to ensure that no build-up of re- sistant organisms occurs in the production and distributing systems. This can be effected by factory hygiene using hot water, detergent and formalin treatment of filling machines, tanks, pumps, filters, mills, pipes, etc., immediately after use. Microbiological tests on equipment should be made to insure the effectiveness of the cleansing operation. The presence of thousands or hundreds of organisms/swab or ml calls for im- mediate action. Tens may be unavoidable although zero counts can be obtained from areas whose cleanliness is deemed crucial. Ayliffe et al. (26) described an outbreak of meningitis in 14 neurosur- gery patients. The infectious agent was Pseudomonas aeruginosa. An examination of the environment revealed the epidemic strain in a shaving brush used for preparation of the scalp and on the floor of a room oc- cupied by an infected patient. Twenty other strains were isolated from hand creams, sinks, floors, soap trays, sink cloths, and the cap of a bottle of antiseptic. Good general cleanliness is important in controlling pseudomonas con- tamination. And by general cleanliness is meant that of shelves, bins, tables, beneath tables, the under side of shelves, etc. At these points spillage of products mixed with dust, dirt and moisture provide a men- struum for the development of resistant pseudomonad strains. Two incidents illustrate the diligence necessary in meeting a pseu- domonas problem within a plant. 1. A strain of pseudomonas had adapted to a pharmaceutical steriod cream. The microbial content was monitored through the mixing ket- tle, filter, pump, homogenizer, aging tank, pipelines, and filling machines. Each element in the process was scrupulously cleaned and sterilized, and yet the very next batch had to be rejected. The number of organisms in the product was so large that it could only have been introduced by a massive inoculation. The only element in the chain that had not been dismantled had been an in-place pipe delivering the emulsion from tank to filler. The line, however, had been cleaned and formalin-sterilized and zero plate counts were obtained from the effluent to prove it. It was found, on breaking into the pipe, that the water had cleaned the bottom oval of the pipe, while the top oval, because of the low pitch, con- tained a layer of cream. Recovery of viable organisms could not be