Since April this year, various tests and experiments on UVC light with a wavelength of 222nm have mainly focused on two aspects: safety to the human body and the inactivation effect of the new coronavirus.
In terms of safety, the latest human test study by the Kobe University research team and Ushio confirmed that after 3 months of exposure to 222nm UVC, the volunteer’s skin test area showed no signs of erythema or other adverse reactions, indicating It is harmless to the human body.
In terms of the inactivation effect of the new coronavirus, in addition to Kobe University and Oxtail, Columbia University is also actively carrying out relevant research. Although experiments have confirmed that the bactericidal effect of 222nm UVC can reach 99.9%, the test subjects are only in seasons with similar structures to the new coronavirus. Sexual coronavirus.
Recently, a research team from Hiroshima University in Japan demonstrated for the first time that 222nm UVC can effectively inactivate the new coronavirus.
The research titled "Effectiveness of 222-nm ultraviolet light on disinfecting SARS-CoV-2 surface contamination" (Effectiveness of 222-nm ultraviolet light on disinfecting SARS-CoV-2 surface contamination) was published on September 4, 2020 in " In the American Journal of Infection Control.
Image source: Hiroshima University
The research paper describes in vitro experiments against the new coronavirus. This study also uses the Care222TM excimer lamp from the oxtail. The researcher sprinkled 100 microliters of the solution containing the new coronavirus on a 9 cm sterile polystyrene plate, placed it in a biological safety cabinet, dried at room temperature, and irradiated with a UVC lamp. The distance between the lamp and the plate was 24 cm.
The experimental results showed that after 30 seconds of irradiation with 222 nm UVC with a light irradiance of 0.1 mW/cm2, the inactivation rate of the new coronavirus culture was 99.7%.
However, because the results of this study are only based on in vitro experiments, the researchers recommend further evaluating the safety of 222 nm UVC in the real world and the effect of disinfecting the surface of the new coronavirus. (Compiled by LEDinside Janice)