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进入二十一世纪以来全球疫情不断暴发,如2002年的重症急性呼吸综合征 (SARS) 、2009年的甲型H1N1流感、2012年的中东呼吸综合征 (MERS) 以及2019年暴发后蔓延全球的新冠 (COVID-19) 疫情,严重威胁着人类健康和社会发展。抗疫过程中传统化学消毒剂 (如氯) 的大量使用,导致了残余消毒剂及消毒副产物引发的次生风险。紫外线 (UV) 作为一种气、水和物体表面的高效、绿色消毒技术,受到广泛关注。国际照明委员会 (Commission Internationale de l’Eclairage,CIE) 按波长将UV分为UV-A (波长315~400 nm) 、UV-B (波长280~315 nm) 和UV-C (波长100~280 nm) ,其中UV-C中又包含真空UV (波长100~200 nm) 、远UV-C (波长200~230 nm) 和灭活UV-C (波长250~280 nm) 。
灭活UV-C (如波长254 nm) 可破坏绝大多数病原微生物的复制过程,使其失去感染性,从而达到高效、低耗的消毒效果,是目前UV消毒领域应用最为广泛的波段。远UV-C可有效杀灭各类病原微生物,但却被长期忽视,尚未广泛应用于消毒领域。主要原因在于其较高的光子能量,较其它波段UV-C更易被介质吸收,从而影响消毒效果。其次,远UV-C光源的电光转化效率 (低于5%) 远低于传统低压汞灯 (约36%) ,故在应用中能耗较高,亦会限制其应用。然而,远UV-C对眼睛和皮肤的伤害较传统灭活UV-C更低,且未发现有效消毒剂量下的远UV-C辐照会对人体造成伤害。因此,基于远UV-C的特性,可开发人机共存条件下的原位UV消毒,以阻断病毒传播,保护人类健康。本文通过对比远UV-C的辐射光源的特点,分析典型病原微生物的灭活机理与效果,以及人体的远UV-C暴露风险,分析其在消毒应用中应解决的关键问题,以期为其应用研究提供参考。
远C波段紫外线消毒的原理及应用前景
Principles and application perspective of far UV-C disinfection
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摘要: 紫外线 (UV) 是一种高效、绿色的消毒技术,广泛应用于气、水和物体表面的病原微生物灭活。远C波段UV (远UV-C,200~230 nm) 消毒所需剂量辐照对人体的伤害尚未被发现,表明远UV-C具备人机共存原位消毒的潜力,因此该技术近期受到关注。概述了远UV-C光源、灭活机制和辐照安全性方面的研究进展:输出主峰位和半峰宽分别为222 nm和4 nm的KrCl准分子灯是最为成熟的消毒用远UV-C光源;远UV-C通过蛋白质损伤和核酸干扰2种途径实现病原微生物灭活,灭活能力较传统UV-C (如254 nm) 更强;尚未发现消毒所需剂量的远UV-C辐照导致的健康危害,如红斑和角膜炎。而在实际应用中,应谨慎对待高剂量远UV-C辐照暴露,确保在现有实验证据基础上,逐步提高远UV-C安全使用的剂量阈值,并考虑与通风系统或臭氧淬灭系统协同使用以避免伴生臭氧造成的二次伤害。本文旨在为远UV-C在高效灭活病原微生物、阻断高传染性疾病传播领域的应用提供参考。Abstract: Ultraviolet (UV), as an efficient and green disinfection technology, has been widely applied to inactivate the pathogens in air, water, and surface. Recently, far UV-C radiation (200-230 nm) has drawn great attention, as it is harmless to human within the normal dose range for disinfection, which has great potential to conduct in situ disinfection with human presence.An overview on far UV-C light sources, inactivation mechanisms, and human health and safety to far UV-C exposure was provided in this article. It was found that krypton-chloride (KrCl) excimer lamps with a main peak at 222 nm and half-peak width at 4 nm were the most mature far UV-C light sources for disinfection, far UV-C inactivated pathogenic microorganisms through protein damage and nucleic acid interfere,and the inactivation ability of far UV-C was stronger than that of traditional UV-C (such as 254 nm). No adverse health effects such as erythema and photokeratitis had been reported for far UV-C irradiation within the dose range required by regular disinfection. However, high dose of far UV-C radiation should still be used with caution in practical applications, where the maximum safe dose should be determined based on experimental evidence and increased gradually. Meanwhile, the use of far-UV-C in collaboration with ventilation system or ozone quenching system should be considered to avoid secondary damage caused by associated ozone. Overall, this article will provide reference for efficient and secure application of far UV-C in disinfection and control of highly infectious epidemics.
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Key words:
- far UV-C /
- krypton-chloride excimer lamps /
- disinfection /
- secutiry /
- human-machine coexistence
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表 1 远UV-C (222 nm) 和灭活UV-C (254 nm) 对致病微生物和受试微生物的剂量响应关系
Table 1. Dose-response data of pathogenic and challenge microorganisms radiated by far UV-C (222 nm) and UVGI (254 nm)
病毒种类 波长/nm 达到相应灭活率所需UV剂量/(mJ·cm−2) 灭活速率常数/
(cm2·mJ−1)文献 1-lg 2-lg 3-lg 4-lg SARS-CoV-2 222a) (含滤光片) 1.6 3.1 4.7 6.3 0.64 [9] SARS-CoV-2 222 (含滤光片) 0.7 1.4 2.1 2.8 1.42 [8] SARS-CoV-2 222 0.7 1.3 2.0 2.6 1.52 [8] SARS-CoV-2 254b) 1.3 2.5 3.8 5.1 0.79 [8] SARS-CoV-2 254 1.7 4.2 5.1 6.8 0.59 [10] MHV 222 (含滤光片) 1.0 1.9 2.9 3.9 1.03 [11] MHV 222 0.8 1.6 2.5 3.3 1.22 [11] MHV 254 1.1 2.2 3.2 4.3 0.93 [11] HCoV 229E 222 (含滤光片) 1.2 2.4 3.6 4.8 0.84 [11] HCoV 229E 222 0.8 1.5 2.3 3.0 1.33 [11] HCoV 229E 254 1.7 3.4 5.1 6.8 0.59 [11] Phi 6 222 (含滤光片) 2.8 5.6 8.3 11.1 0.36 [11] Phi 6 222 3.7 7.4 11.1 14.8 0.27 [11] Phi 6 254 33.3 66.6 100.0 133.3 0.03 [11] T1UV 222c) 2.7 5.5 8.2 11.0 0.37 [12] T1UV 254c) 4.3 8.5 12.8 17.0 0.23 [12] MS2 222c) 8.9 17.7 26.6 35.5 0.11 [12] MS2 254c) 16.0 33.6 53.4 77.6 0.05 [12] 注:a) 222 nm如没有特殊标注均为KrCl准分子灯;b) 254 nm如没有特殊标注均为低压汞灯;c) NT242系列可调谐激光器 (NIST)。 -
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