Background The COVID-19 pandemic sharply increased the demand for ethanol-based gel hand sanitizers, leading to a shortage of these products. Consequently, regulatory health agencies worldwide have altered their regulatory guidelines on ethanol quality to meet this high demand, raising concerns about product quality. Objective The aim of this study was to quantify ethanol content and to qualitatively assess common impurities in ethanol-based gel hand sanitizers by headspace (HS) gas chromatography (GC) with flame ionization detector (FID). Methods To quantify the ethanol content, 0.10 g of the sample was weighed in a 20 mL HS vial and 5 mL of deionized water was added. Regarding the qualitative approach, 0.25 g of the sample was weighed and 4 mL of deionized water was added. The samples were incubated and then 400 µL of the HS was injected into the GC/FID. Forty-eight products purchased in Brazil were analyzed. Results Thirteen products presented at least one nonconformity regarding the ethanol quantity. Two samples presented an average ethanol concentration below the lower limit considered effective. Twelve samples presented acetaldehyde or ethyl acetate. Conclusion The huge demand for ethanol-based gel hand sanitizers may have impacted their quality. Because concern with proper hand hygiene tends to remain an issue for a long period, more studies about quality control of hand sanitizers will be needed. Highlights A simple and fast HS-GC/FID method to quantify ethanol in ethanol-based gel hand sanitizers was developed, validated, and applied to commercial samples in Brazil. The regulatory authorities must be more vigilant to ensure that the commercially available products meet the recommended specifications.

中文翻译：

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使用火焰离子化检测器 (HS-GC/FID) 的顶空气相色谱法对基于乙醇的洗手液中的乙醇进行定量

背景 COVID-19 大流行急剧增加了对基于乙醇的凝胶洗手液的需求，导致这些产品短缺。因此，世界各地的卫生监管机构已经改变了他们对乙醇质量的监管指南，以满足这种高需求，从而引发了对产品质量的担忧。目的 本研究的目的是通过配备火焰离子化检测器 (FID) 的顶空 (HS) 气相色谱 (GC) 对乙醇基凝胶洗手液中的常见杂质进行量化和定性评估。方法 为了量化乙醇含量，在 20 mL HS 样品瓶中称量 0.10 g 样品，并加入 5 mL 去离子水。关于定性方法，称取 0.25 g 样品并加入 4 mL 去离子水。对样品进行孵育，然后将 400 µL HS 注入 GC/FID。分析了在巴西购买的 48 种产品。结果 13 种产品的乙醇含量至少存在一项不符合项。两个样品的平均乙醇浓度低于被认为有效的下限。十二个样品呈现乙醛或乙酸乙酯。结论 对乙醇基凝胶洗手液的巨大需求可能影响了其质量。由于对适当手部卫生的关注往往会长期存在，因此需要对洗手液的质量控制进行更多研究。亮点 一种简单快速的 HS-GC/FID 方法可用于定量乙醇凝胶洗手液中的乙醇，并在巴西开发、验证并应用于商业样品。