Periz G, Misock J, Huang M-C Jo, Dewan K, Sadrieh N
Office of Cosmetics and Colors, Center for Food Safety and Applied Nutrition, Food and Drug Administration, College Park, MD, USA.
Lett Appl Microbiol. 2018 Jul;67(1):32-38. doi: 10.1111/lam.12995. Epub 2018 May 7.
In an attempt to assess cosmetics containing 'nontraditional' preservatives, 93 eye area cosmetic products were selected based on labelled or marketed claims that these products were 'green', 'natural', 'paraben-free', 'preservative-free' or contained nontraditional preservatives (e.g. botanical extracts). Products were analysed for water activity, pH and microbiological content, which included enumeration of aerobic micro-organisms, detection of microbial growth after a 7-day enrichment and identification of microbial isolates. The survey found that 60% (56/93) of the eye area cosmetics were free of microbiological growth under test conditions, 32% (30/93) showed the presence of micro-organisms at low levels (<100 CFU per ml or g) and 8% (7/93) showed microbiological growth at higher levels (> 100 CFU per ml or g). Gram-positive bacteria such as Bacillus and Staphylococcus were the dominant genera identified in these cosmetic products, whereas Gram-negative species were relatively uncommon. The survey found a positive association between lower water activity cosmetics and the presence of micro-organisms in these products. Similarly, colour cosmetics were more likely to contain micro-organisms than noncolour cosmetics. The most represented micro-organisms in the survey were from genus Bacillus, suggesting that the natural raw materials are the likely source of observed microbial loads.
In the United States, cosmetic products are regulated postmarket; therefore, surveillance programmes are one of FDA's most important tools for monitoring microbiological safety of cosmetics. 'Traditional' preservatives, such as parabens and formaldehyde releasers, are perceived unfavourably by some consumers, resulting in cosmetic manufacturers increasingly using 'nontraditional' preservatives. FDA conducted an analytical survey of eye area cosmetics that claimed to be free of traditional preservatives and determined microbiological loads in tested products. This study explores the association of microbial loads with the physical and chemical characteristics of the cosmetic products, and points to the limits of preservative activity in cosmetics.
为了评估含有“非传统”防腐剂的化妆品，基于产品标签或市场宣传声称这些产品是“绿色”“天然”“无对羟基苯甲酸酯”“无防腐剂”或含有非传统防腐剂（如植物提取物），挑选了93种眼部化妆品。对产品进行水活性、pH值和微生物含量分析，包括需氧微生物计数、7天富集培养后微生物生长检测以及微生物分离株鉴定。调查发现，60%（56/93）的眼部化妆品在测试条件下无微生物生长，32%（30/93）显示存在低水平微生物（每毫升或克<100 CFU），8%（7/93）显示微生物生长水平较高（每毫升或克>100 CFU）。在这些化妆品中鉴定出的主要革兰氏阳性菌属如芽孢杆菌属和葡萄球菌属，而革兰氏阴性菌相对较少。调查发现水活性较低的化妆品与这些产品中微生物的存在之间存在正相关。同样，彩妆比非彩妆更有可能含有微生物。调查中最常见的微生物来自芽孢杆菌属，这表明天然原料可能是观察到的微生物负荷的来源。
在美国，化妆品在上市后受到监管；因此，监测计划是美国食品药品监督管理局（FDA）监测化妆品微生物安全性的最重要工具之一。一些消费者对“传统”防腐剂如对羟基苯甲酸酯和甲醛释放剂看法不佳，导致化妆品制造商越来越多地使用“非传统”防腐剂。FDA对声称不含传统防腐剂的眼部化妆品进行了分析调查，并确定了测试产品中的微生物负荷。本研究探讨了微生物负荷与化妆品物理和化学特性之间的关联，并指出了化妆品中防腐剂活性的局限性。
