In a 2018 survey, U.S. Food and Drug Administration (FDA) identified microbial contamination in 42 (49%) of 85 unopened tattoo and permanent makeup (PMU) inks purchased from 13 manufacturers in the US between November 2015 and April 2016. To confirm the results of our previous survey, we evaluated the level of microbial contamination in an additional 27 samples from 10 manufacturers from September 2017 to December 2017, including 21 unopened tattoo and PMU inks which were selected based on our previous survey results and 6 ink diluents that were not previously analysed. Aerobic plate count and enrichment culture methods from the FDA’s Bacteriological Analytical Manual revealed 11 (52%) out of 21 inks, from six manufacturers, were contaminated with micro‐organisms, with contamination levels up to 3·6 × 108 CFU per gram, consistent with our previous survey results. We identified 25 bacterial strains belonging to nine genera and 19 species. Strains of Bacillus sp. (11 strains, 44%) were dominant, followed by Paenibacillus sp. (5 strains, 20%). Clinically relevant strains, such as Kocuria rhizophila and Oligella ureolytica, were also identified, as similar to the findings in our previous survey. No microbial contamination was detected in any of the six ink diluents.

中文翻译：

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在美国销售的纹身和永久化妆墨水的微生物污染：一项后续研究

在 2018 年的一项调查中，美国食品和药物管理局 (FDA) 在 2015 年 11 月至 2016 年 4 月期间从美国 13 家制造商购买的 85 种未开封的纹身和永久化妆 (PMU) 墨水中，发现其中 42 种 (49%) 存在微生物污染。根据我们之前的调查结果，我们评估了 2017 年 9 月至 2017 年 12 月期间来自 10 个制造商的另外 27 个样本的微生物污染水平，包括根据我们之前的调查结果选择的 21 种未开封的纹身和 PMU 墨水以及 6 种墨水稀释剂。之前没有分析过。FDA 的细菌学分析手册中的需氧菌落计数和富集培养方法显示，来自 6 家制造商的 21 种墨水中有 11 种（52%）被微生物污染，污染水平高达每克 3·6 × 108 CFU，与我们之前的调查结果一致。我们确定了属于 9 属和 19 种的 25 株细菌。芽孢杆菌菌株。（11 株，44%）是显性的，其次是类芽孢杆菌。（5 株，20%）。临床相关菌株，如 Kocuria rhizophila 和 Oligella ureolytica，也与我们之前的调查结果相似。在六种墨水稀释剂中的任何一种中均未检测到微生物污染。