Amid the coronavirus disease 2019 pandemic, demand for cloth face masks containing nanosilver has increased. Common product claims such as “antiviral” and “antimicrobial” can be attractive to buyers seeking to protect themselves from this respiratory disease, but it is important to note that filtration capabilities are the main factor to prevent virus transmission and that antimicrobial ability is a secondary protection factor. Silver has long been known to be antibacterial, and growing research supports additional antiviral properties. In this study, 40 masks claiming to contain silver were evaluated for substantiated antiviral and antimicrobial claims using methods available to the public. Criteria for determining the validity of substantiated claims included the use of patented technology, international certification for antimicrobial and/or antiviral textile by ISO or ASTM, EPA pesticide registration, and peer-reviewed literature. Our analysis showed that, of the 40 masks, 21 had substantiated claims. Using scanning electron microscopy (SEM), two of the substantiated face masks (A and B) were examined for silver identification for further confirmation. Mask A uses silver and copper ions attached to zeolite particles; the zeolite particles discovered through SEM were approximately 90–200 nm in diameter. In mask B, particles of silver and titanium at the 250 nm size were found. In conclusion, these certifications or patents are not enough to determine credibility, and stricter regulations by federal agencies on product testing for manufacturers that make claims are necessary to ensure the efficacy of the product advertised, as well as a cloth face mask inhalation standard.

中文翻译：

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含银布口罩：评估现状

在 2019 年冠状病毒大流行期间，对含有纳米银的布口罩的需求有所增加。“抗病毒”和“抗菌”等常见产品声明可能对寻求保护自己免受这种呼吸道疾病侵害的买家有吸引力，但重要的是要注意，过滤能力是防止病毒传播的主要因素，抗菌能力是次要因素保护系数。长期以来人们都知道银具有抗菌作用，并且越来越多的研究支持银具有额外的抗病毒特性。在这项研究中，使用公众可用的方法对 40 个声称含有银的口罩进行了经证实的抗病毒和抗菌声称的评估。确定经证实的声明有效性的标准包括专利技术的使用、ISO 或 ASTM 的抗菌和/或抗病毒纺织品国际认证、EPA 农药登记以及同行评审文献。我们的分析显示，在 40 个口罩中，有 21 个的说法得到证实。使用扫描电子显微镜 (SEM)，检查两个已证实的口罩（A 和 B）的银鉴定，以进一步确认。面膜A使用附着在沸石颗粒上的银离子和铜离子；通过 SEM 发现的沸石颗粒直径约为 90-200 nm。在掩模B中，发现了尺寸为250nm的银和钛颗粒。总之，这些认证或专利不足以确定可信度，联邦机构有必要对做出声明的制造商进行更严格的产品测试规定，以确保所宣传产品的功效以及布口罩吸入标准。