by Roger Ham 6/3/20
On April 24th, President Trump created a media uproar when he suggested that hitting the body with Ultraviolet light or disinfectants might be effective in fighting the Corona virus. While the media jumped on the idea of swallowing bleach, the idea of using UV light to fight pathogens is already being used widely and new breakthroughs will have an important role in fighting the current pandemic.
It has been known for a hundred years that Ultraviolet (UV) light can kill pathogens. Hospitals, public drinking water utilities, waste water utilities and many others already use UV light to sanitize materials. Subway cars and buses can be sanitized using UV light as well. However, up until now, this sanitization had to be done when no humans were present in the spaces being irradiated because UV light can cause skin damage or cancer, as well as eye disease. A major advance in this area is now awaiting FDA approval and could radically change our whole approach to pathogens in general and to COVID-19 in particular.
UV light occupies the part of the electromagnetic spectrum just beyond visible light and extends from 400 nm down to about 100 nm. The UV light can be further divided into UV-A, UV-B and UV-C. UV-A and UV-B are the cause of sunburn on a summer day, but UV-C can’t penetrate the atmosphere, so we have no exposure to that segment of the UV spectrum. That’s a good thing, because it is UV-C, at a wavelength of ~254 nm which is typically used to sanitize operating rooms in hospitals or disinfect water. Purple Sun is one of the companies manufacturing this type of equipment for hospitals. Robots, costing $100,000 are used to go into areas autonomously to sanitize when no people are present.
However, recent research has shown that “Far UV-C” light at the specific wavelength of 222 nm is not only far more effective than light at 254 nm at killing pathogens (including the drug- resistant “super bugs”), but because it cannot penetrate a single layer of dead cells on your skin or even the film of water covering your eyes, it is completely harmless to people. This would mean that “Far UV-C” lights could be installed in operating rooms, hospital rooms, buses, airplanes, cruise ships, airport or bus terminals, theaters, grocery stores, restaurants, gyms, etc. You get the idea—these lights could be installed in any public space to continuously sanitize the air as well as surfaces while people use them. Lights in operating rooms could prevent infections which occur during surgery. Hand-held wands can be used to sanitize high-touch areas in hospital patient’s rooms or nursing homes in seconds without having to remove the patient. The critical N95 masks which have been in very short supply can be sanitized and reused by exposure to Far UV-C light.
The MTA in New York City has begun a pilot program using Far UV-C light to disinfect subway cars, buses and some occupational facilities. They have purchased around 200 units from a Colorado based company, Puro Lighting, at a cost of $1 million. Phase Two of the pilot program will expand testing to include Metro North and the LIRR. If the lamps perform as expected, competitive bidding will be used to line up long term contracts.
This sanitization is being done overnight, when the cars are empty and no people are present, but it is also possible to install overhead lighting for use with passengers. Rather than getting on a subway car that was sanitized sometime last night, you could ride in one where every exposed surface is continuously being sanitized. This will make people much safer and comfortable coming out of quarantine.
Two bars in Washington, DC have announced that when they reopen, patrons will be encouraged to enter via a UV Cleanse Portal, which looks something like the magnetometers used at every airport. For New Yorkers, the Magnolia Bakery on Columbus Ave. on the Upper West Side of Manhattan, is installing a UV Cleanse Portal as well as recessed ceiling lights. Patrons will raise their arms and slowly spin for 20 seconds while a low dose of Far UV-C light kills 90% of all germs on the surface of their clothes. While this would not prevent all airborne transmission from an infected individual, it would drastically reduce the viral load on surfaces. Units are also available to install in HVAC systems, so that air in office buildings, schools and other enclosed spaces can also be sanitized.
One company holding multiple patents on this technology is Eximer Wave Sterilray based is Somersworth, NH. On their website, you can view peer reviewed medical studies done on mice in Japan, showing no skin or eye damage after prolonged exposure to relatively high doses of Far UV-C light. The UV Cleanse Portals installed in the DC bars and the bakery in Manhattan are manufactured by Healthe lighting in Melbourne, FL. The founder and CTO of Healthe is Fred Maxik, a former NASA scientist who worked on the lighting system for the International Space Station.
Dr. David J. Brenner, a professor of Radiation Biophysics and head of the Center for Radiological Research at Columbia University in NYC has studied Far UV-C light for many years. He did a TED Talk in December 2017 on his personal war against drug-resistant superbugs and the efficacy of Far UV-C light. It is difficult to find a news story or research paper which does not cite Dr. Brenner’s extensive research. He is currently nearing the end of a year-long safety study on the effects of Far UV-C light on hairless mice. The mice are examined every two weeks for skin lesions and eye damage. After nearly one year of exposure 8 hours per day, there is absolutely no evidence of skin or eye damage. Dr. Brenner has been involved with the testing by the MTA and many others interested in applying this technology in the fight against COVID-19. He has said that the major issue now is how long it will take to massively expand production of the lamps and make them available as widely as possible.