Far-UVC lamps found to kill coronavirus but do not harm humans
A new type of ultraviolet (UV) lamp – with low-frequency radiation – has been found to destroy viruses within minutes of surface contact and does not harm human skin. Researchers at the University of Columbia’s Center for Radiological Research (CRR), in New York, are currently experimenting with such lamps for use against SARS-CoV-2 and other viruses.
While commonly-known UV radiation like UVA and UVB rays can penetrate and damage human skin, a third type, UVC radiation, is more dangerous to airborne viruses – far-UVC lamps are highly effective at killing bacteria, viruses and molds and have been employed for some time in hospitals and other settings where disinfection is necessary. Humans should be safe when exposed as UVC rays cannot penetrate the multiple layers of skin, or the eyes. (Although extremely dangerous, UVC rays never actually reach Earth because the ozone absorbs it.)
Tests performed by researchers at a highly bio-secure laboratory at CRR showed the far-UVC rays, with a short wavelength of just 222 nanometres, killed the coronavirus within minutes of exposure.Additionally, the researchers exposed mice to far-UVC rays for eight hours a day, five days a week – far longer than any human can expect to be exposed to this kind of radiation; the intensity of the radiation that the mice were exposed to was also 20 times greater than normal.
Despite all this, according to the Director of Columbia’s Center for Radiological Research, David Brenner, the mice were chipper, as usual, “They were very happy – and very cute as well.”
Brenner’s lab has been experimenting with far-UVC lamps against germs for a while – they have previously showed that UVC radiation could kill MRSA bacteria and influenza viruses – responsible for surgery-associated infections and the flu, respectively – without harming human or mouse skin.
Thanks to the promising findings, the researchers envision a future with overhead, low-level far-UVC lighting in public locations to limit the airborne transmission and spread of microbial disease. At present, such lamps might not only curb the spread of the coronavirus but might also avert other pandemics in the future.