318 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS standard for that particular product. This has ensured greater flexibility in supplying different countries from one centre. As a result of 4 years' experience there is good confidence that because of the MQC programme the products leaving the plants are pure and whole- some. ORGANISMS WHICH HAVE CAUSED PROBLEMS A review of the records places the culprits in the following order of importance. 1. Achromobacter 2. Pseudomonas. 3. Bacillus. It is surprising perhaps that the Enterobacteriaceae and Micrococcaceae do not figure in our list but the survival value of pathogens in plants such as Escherichia coli and Staphylococcus aureus is essentially nil and they have never been a cause of control breakdown. Without doubt in places as far apart as Liverpool, Madrid and Johannesburg the Achromobacter have been the major problem. Both Achromobacter liquefaciens and A. guttatus have been isolated from mains water, deionized water, filling lines and finished product. They have caused a major rethink in the provision of deionized water to points in the plant and the use of filtered and boiled water for rinsing procedures. Pseudomonas aeruginosa and another Pseudomonas spp. have been responsible on two occasions for the phenomenon of adaption. On these two occasions the organisms were metabolizing a detergent present in the two products and were totally resistant to the paraben pre- servation in one case and benzalkonium chloride in the other. One plant had to be closed for sterilization and in the other the filling equipment was scrapped and replaced. This latter example serves to illustrate the problems that can be met in the factory environment when Pseudomonas aeruginosa is present. J Early in 1972 an overseas plant reported contamination in an aqueous topical non-sterile pharmaceutical. Filled stock was contaminated with an organism growing at both 24øC and 37øC on Nutrient Agar. This organism was present between 105 and 10 ? ml -• and produced an intense green pigment. It was rapidly established that bulk product and packaging material were both free from contamination and it was, therefore, the filling equipment

MICROBIOLOGICAL QUALITY CONTROL 319 which was the most likely source of contamination. An immediate monitor- ing of the filling equipment, raw materials and water, personnel, packaging and bulk product was undertaken. Contamination was only found 'down- stream' of a rotation pump feeding bulk into the stationary line. Flushing through the system with sterile water and counting at the filling nozzles showed that approximately 10 a organisms ml -x were being delivered. The entire filling equipment was dismantled and replaced with stainless steel parts throughout and the old pump was scrapped. A daily disinfection procedure was drawn up and process workers instructed in its use, With this new equipment and standard operating procedure the plant has been free of all contamination for over 2 years. The analysis of plant water showed that contamination was minimal and did not contain Ps aeruginosa but there were Ps spp. present. The Ps aeruginosa isolated produced intense green pigmentation on nutrient agar, the pigmented colonies showed fluorescence and the plates smelled of methylamine. Oxydase was positive, it grew on and in Centrimide agar and broth and was typed as Pyocine 36 B. When inoculated from contaminated product it could utilize Triton WR1339 as its sole source of carbon. Triton WR1339 is the non-ionic detergent present in the topical product. Prompt response to the initial finding, the quarantining of stock and immediate clean up procedures prevented a major production disaster. Final rinsing procedures after disinfection but before filling are now carried out with boiled deionized water or deionized water filtered through a final bacterial filter at the point of use. The use of mains water or non- sterilized deionized plant water does allow inoculation of equipment with various waterborne bacteria. The level of inoculation is extremely low but where there has been a breakdown in routine production the frequency of contamination problems rises considerably. For example a cosmetic lotion had two bulk batches pooled to adjust viscosity and on filling was shown to be contaminated with Achromobacter liquefaciens which was present in the plant water. The Achrornobacter has been found somewhat more resistant to the usual parben preservatives so now this organism is included routinely in challenge tests carried out by R & D. Achrotnobacter is defined as Gram negative motile or non-motile rods which do not form pigment and whose optimum growth temperature lies at 30øC or below. An exact name has only been put to two species but the vast majority of isolates are of these two species, A. liquefaciens and A. guttatus. A. liquefaciens liquifies gelatine, A. guttatus does not, and neither produce nitrites from nitrates.