Far UV-C Handwashing is Urgently Needed

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WaveHalo is a faster, safer, and more effective solution for cleaning hands and phones than washing with soap and water or hand sanitizer. WaveHalo uses 222nm ultraviolet-light (Far-UVC) to clean hands and handheld objects such as phones in 5 seconds. First, Far-UVC reduces bacteria, viruses, and some spores on surfaces and in the air. Second, repeated safety testing shows no risk to human skin from Far-UVC, even at extreme doses. Unfortunately, WaveHalo can only be used 3 times daily under the antiquated, 45-year-old recommended exposure limits. These limits are scheduled to increase to match modern-day studies, however, that may take months or years.


The problems with conventional hand cleaning:

The current ways we clean our hands leaves behind pathogens and can damage our skin. Handwashing for 20 seconds with soap and water is the CDC recommendation and first defense against community-spread illnesses [1] . This method, however, depends on rigorous scrubbing and duration. Unfortunately, only 5.3% of Americans wash their hands for 15 seconds [2], limiting the benefits of hand-washing. The remaining pathogens create an individual and community health risk. Although alcohol-based sanitizers are more reliable, they are harsh on skin after repeated use and they are costly. Painful dry skin caused by sanitizers has been shown in studies to actually dissuade further use among 52% of nurses and 44% of healthcare workers [3,4]. With the increase of handwashing and sanitizer use due to the pandemic, contact dermatitis and eczema has increased in frontline healthcare workers and children alike [3,5,6]. Furthermore, pathogens have begun building alcohol tolerance, causing increased cases of hospital-acquired infections due to reliance on hand sanitizers between patient encounters [7,8]. Consequently, Far-UVC is a faster, better, chemical and contact-free solution.


Far-UVC is effective against pathogens:

Far-UVC light already removes a wide range of pathogens from surfaces, food, water, and the air. Far-UVC light is absorbed by the DNA and proteins of pathogens, causing dose-dependent damage and rendering them unable to infect or reproduce [9,10]. Far-UVC has been shown to be effective against bacteria that are commonly treated by antibiotics, such as K. pneumoniae, Salmonella typhimurium, and M. tuberculosis [11-13], as well as bacteria that are antibiotic resistant, such as S. aureus (MRSA) and C. difficile [14-16]. Additionally, bacterial spores that are resistant to antibiotics and most conventional cleaning methods are susceptible to Far-UVC light, making UVC the ideal countermeasure for Anthrax and the spores that lead to tetanus and C. difficile infections [14,17,18]. Further, Far-UVC can also deactivate both enveloped and non-enveloped viruses. Use of UVC has been shown to lead to reduced viral numbers [19-21] and instances of community spread [13] for Tuberculosis, influenza, and SARS-CoV2. Commercially, Far-UVC light is already used in clinical settings to cleanse surgical rooms and medical equipment22 and industrially to sanitize water or food [23-26], but not used to sanitize human skin. The ability of Far-UVC to effectively sanitize a broad range of infectious agents (bacteria, spores, fungi, and viruses) should be leveraged to promote hand sanitization and better community health.


Far-UVC is skin-safe

Far-UVC is safe for use on human skin as shown in repeated studies. Skin has a natural outer, dead layer to protect the still living layer beneath from drying out and being damaged [27]. Because Far-UVC light wavelengths are short, they are rapidly absorbed or scattered by the top, dead layer of skin, leaving the underlying living tissue untouched [27-30]. Far-UVC did not cause damage in mice skin or eyes after exposure of up to 450mJ/cm2 [30,31], or in human skin after exposure of up to 6,100mJ/cm2 [29, 32-34]. However, these values far surpass the 45-year-old American Conference for Governmental Industrial Hygienists (ACGIH) standard of 22mJ/cm2 (the standard relied on by the FDA, EPA and safety laboratories). Fortunately, ACGIH appears to recognize current scientific understanding and has published its intent to raise these limits to ~600mJ/cm2 [35]. Unfortunately, these updates can take months or years to be approved.


Helping People Faster

Because of the public health emergency, the FDA has the authority to make EUAs that could allow for Far-UVC hand sanitization to immediately operate at the proven higher standards. For example, WaveHalo uses the 7mJ/cm2 Far-UVC per cleaning cycle. Under current standards, this is 3 daily uses. Under the future standards, this March 19, 2021 would be 85 daily uses. The increased number of uses would mean clean hands (and phones) without the painful cracking and bleeding for healthcare workers, frontline food-service, and other high-frequency handwashing professionals.


- Dr. Janet Price

PhD Molecular, Cellular, and Developmental Biology  - University of Michigan

Vice President of Research and Regulatory Affairs

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1. CDC. Jan. 11, 2021 2021. Handwashing: Clean Hands Saves Lives, on The Centers for Disease Control and Prevention. https://www.cdc.gov/handwashing/index.html. Accessed Feb 1, 2021.


2. Borchgrevink CP, Cha J, Kim S. 2013. Hand washing practices in a college town environment. J Environ Health 75:18-24.

3. Cimiotti JP, Marmur ES, Nesin M, Hamlin-Cook P, Larson EL. 2003. Adverse reactions associated with an alcohol-based hand antiseptic among nurses in a neonatal intensive care unit. Am J Infect Control 31:43-8.

4. McKenzie SN, Turton P, Castle K, Clark SM, Lansdown MR, Horgan K. 2011. Alcohol hand abuse: a cross-sectional survey of skin complaints and usage patterns at a large UK teaching hospital. JRSM Short Rep 2:68.


5. Ibler KS, Jemec GBE, Agner T. 2012. Exposures related to hand eczema: a study of healthcare workers. Contact Dermatitis 66:247-253.

7. Vogel L. 2011. Hand sanitizers may increase norovirus risk. CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne 183:E799-E800.


8. Pidot SJ, Gao W, Buultjens AH, Monk IR, Guerillot R, Carter GP, Lee JYH, Lam MMC, Grayson ML, Ballard SA, Mahony AA, Grabsch EA, Kotsanas D, Korman TM, Coombs GW, Robinson JO, Gonçalves da Silva A, Seemann T, Howden BP, Johnson PDR, Stinear TP. 2018. Increasing tolerance of hospital Enterococcus faecium to handwash alcohols. Sci Transl Med 10.


9. Rastogi RP, Richa, Kumar A, Tyagi MB, Sinha RP. 2010. Molecular mechanisms of ultraviolet radiation-induced DNA damage and repair. Journal of nucleic acids 2010:592980-592980.


10. Vatansever F, Ferraresi C, de Sousa MVP, Yin R, Rineh A, Sharma SK, Hamblin MR. 2013. Can biowarfare agents be defeated with light? Virulence 4:796-825.


11. Chang JCH, Ossoff SF, Lobe DC, Dorfman MH, Dumais CM, Qualls RG, Johnson JD. 1985. UV Inactivation of Pathogenic and Indicator Microorganisms. Applied and Environmental Microbiology 49:1361-1365.


12. Giese N, Darby J. 2000. Sensitivity of microorganisms to different wavelengths of UV light: implications on modeling of medium pressure UV systems. Water Research 34:4007-4013.


13. Mamahlodi MT. 2019. Potential benefits and harms of the use of UV radiation in transmission of tuberculosis in South African health facilities. Journal of public health in Africa 10:742-742.


14. Nerandzic MM, Fisher CW, Donskey CJ. 2014. Sorting through the wealth of options: comparative evaluation of two ultraviolet disinfection systems. PloS one 9:e107444-e107444.


15. Clauß M. 2006. Higher effectiveness of photoinactivation of bacterial spores, UV resistant vegetative bacteria and mold spores with 222 nm compared to 254 nm wavelength. Acta hydrochimica et hydrobiologica 34:525-532.


16. Buonanno M, Ponnaiya B, Welch D, Stanislauskas M, Randers-Pehrson G, Smilenov L, Lowy FD, Owens DM, Brenner DJ. 2017. Germicidal Efficacy and Mammalian Skin Safety of 222-nm UV Light. Radiation Research 187:493-501, 9.


17. Wood JP, Archer J, Calfee MW, Serre S, Mickelsen L, Mikelonis A, Oudejans L, Hu M, Hurst S, Rastogi VK. 2020. Inactivation of Bacillus anthracis and Bacillus atrophaeus spores on different surfaces with ultraviolet light produced with a low-pressure mercury vapor lamp or light emitting diodes. Journal of Applied Microbiology n/a.


18. Cohen JE, Wang R, Shen R-F, Wu WW, Keller JE. 2017. Comparative pathogenomics of Clostridium tetani. PloS one 12:e0182909-e0182909.

19. Narita K, Asano K, Naito K, Ohashi H, Sasaki M, Morimoto Y, Igarashi T, Nakane A. 2020. Ultraviolet C light with wavelength of 222 nm inactivates a wide spectrum of microbial pathogens. Journal of Hospital Infection 105:459-467.


20. Buonanno M, Welch D, Shuryak I, Brenner DJ. 2020. Far-UVC light (222 nm) efficiently and safely inactivates airborne human coronaviruses. Scientific Reports 10:10285.


21. Kitagawa H, Nomura T, Nazmul T, Omori K, Shigemoto N, Sakaguchi T, Ohge H. 2020. Effectiveness of 222-nm ultraviolet light on disinfecting SARS-CoV-2 surface contamination. American Journal of Infection Control doi:10.1016/j.ajic.2020.08.022.


22. Ponnaiya B, Buonanno M, Welch D, Shuryak I, Randers-Pehrson G, Brenner DJ. 2018. Far-UVC light prevents MRSA infection of superficial wounds in vivo. PLoS One 13:e0192053.


23. Lakretz A, Ron EZ, Mamane H. 2010. Biofouling control in water by various UVC wavelengths and doses. Biofouling 26:257-67.


24. Oh C, Sun PP, Araud E, Nguyen TH. 2020. Mechanism and efficacy of virus inactivation by a microplasma UV lamp generating monochromatic UV irradiation at 222 nm. Water Research 186:116386.


25. Wang Y, Araud E, Shisler JL, Nguyen TH, Yuan B. 2019. Influence of algal organic matter on MS2 bacteriophage inactivation by ultraviolet irradiation at 220 nm and 254 nm. Chemosphere 214:195-202.


26. Kang JW, Kim WJ, Kang DH. 2020. Synergistic effect of 222-nm krypton-chlorine excilamp and mild heating combined treatment on inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium in apple juice. Int J Food Microbiol 329:108665.


27. Anderson RR, Parrish JA. 1981. The Optics of Human Skin. Journal of Investigative Dermatology 77:13-19.


28. Fukui T, Niikura T, Oda T, Kumabe Y, Ohashi H, Sasaki M, Igarashi T, Kunisada M, Yamano N, Oe K, Matsumoto T, Matsushita T, Hayashi S, Nishigori C, Kuroda R. 2020. Exploratory clinical trial on the safety and bactericidal effect of 222-nm ultraviolet C irradiation in healthy humans. PLoS One 15:e0235948.


29. Hickerson RP, Conneely MJ, Tsutsumi SKH, Wood K, Jackson DN, Ibbotson SH, Eadie E. 2021. Minimal, superficial DNA damage in human skin from filtered far-ultraviolet-C (UV-C). Br J Dermatol doi:10.1111/bjd.19816.


30. Yamano N, Kunisada M, Kaidzu S, Sugihara K, Nishiaki-Sawada A, Ohashi H, Yoshioka A, Igarashi T, Ohira A, Tanito M, Nishigori C. 2020. Long-term Effects of 222-nm ultraviolet radiation C Sterilizing Lamps on Mice Susceptible to Ultraviolet Radiation. Photochemistry and Photobiology 96:853-862.


31. Narita K, Asano K, Morimoto Y, Igarashi T, Nakane A. 2018. Chronic irradiation with 222-nm UVC light induces neither DNA damage nor epidermal lesions in mouse skin, even at high doses. PLOS ONE 13:e0201259.


32. Buonanno M, Welch D, Brenner DJ. 2021. Exposure of Human Skin Models to KrCl Excimer Lamps: The Impact of Optical Filtering. Photochemistry and Photobiology doi:https://doi.org/10.1111/php.13383.


33. Eadie E, Barnard IMR, Ibbotson SH, Wood K. 2021. Extreme Exposure to Filtered Far-UVC: A Case Study. Photochem Photobiol doi:10.1111/php.13385.


34. Aiello AE, Murray GF, Perez V, Coulborn RM, Davis BM, Uddin M, Shay DK, Waterman SH, Monto AS. 2010. Mask use, hand hygiene, and seasonal influenza-like illness among young adults: a randomized intervention trial. J Infect Dis 201:491-8.


35. (ACGIH) ACoGIH. 2020. Ultraviolet Radiation: TLV(R) Physical Agents Documentation, Notice of Intended Change. ACGIH.

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