UV light kills viruses. Why isn't it everywhere?

it wasn't until March of 2020 when it suddenly felt like the air itself was trying to kill us and now a few years removed from a pandemic lockdown and it's still kind of weird to think about viruses and bacteria are these invisible enemies that we just kind of deal with day-to-day and they leave us coughing and sneezing our way through Winters so we wield our sprays and wipes and sanitizers but there is a powerful disinfectant that we've known about for a century and it still isn't part of this toolkit at least not consistently light this is the electromagnetic spectrum you've seen it before literally here where visible light is the light we were talking about as a disinfectant occurs here ultraviolet light there are actually three different different types of UV light that occur at different wavelengths the One Shining down on us from the Sun is mostly UVA and some UVB and that UV does all the things that people think UV is going to do so we can't shine it on people okay it hurts your skin it hurts your eyes it gives you cancer it does that by damaging the DNA in our cells but ironically those same properties that cause cancer also break down viruses and bacteria and stop them from replicating and we've known this since the late 1800s so researchers have been experimenting with low wavelength UV or UVC as a germicide for decades in the 1940s researchers placed UV irradiation Chambers in classrooms now don't worry the UV light was being safely projected into the air above the children so they weren't being directly exposed to it but as air circulated the room it could be cleansed researchers ultimately found that it was effective at stopping the measles virus very effective under 15% of the kids in classrooms with UV were infected compared to over 55% of those in classrooms without it later studies used rodents to test uv's Effectiveness with other diseases like tuberculosis the air was irradiated with ultraviolet light first and the hamsters in the treatment group did not get tuberculosis but these lights needed to be kept above people or hamsters and installed carefully using a costly process called Upper Room UV because even though they operate at a low wavelength it still isn't great to directly blast humans with it day in and day out you know because the cancer thing this method is actually used in a lot of hospitals paired with ventilation to help reduce infection rates but having UV at the top part of the room can't do much to stop the germs being spread between people so more recently researchers began looking for a better way to kill pathogens all around around us they ran studies to determine the most UV light that could be used to kill bacteria and viruses but also minimize harm to humans which brings us to a type of UVC called far UV far UV has a very low wavelength that can't penetrate skin deeply enough to cause damage even in mice specifically bread to be susceptible to cancer this is a field full of tuberculosis hamsters and cancer mice and I feel really bad about it in test Chambers far UV is really effective at killing pathogens this study is from 2020 when well you know what happened in 2020 it showed that fuv was able to kill 99% of Corona viruses in a test chamber and this study found that it was 98% effective at reducing the bacteria that causes staff infections so why isn't it everywhere in order to understand Effectiveness um you first have to understand safety well it's generally accepted that far UV won't give you cancer there are other consequences to Bringing UV light so close to the ground we know really well that when you shine UV lights on air it can cause chemistry to happen UV light produces a molecule called ozone which can be harmful for humans to breathe in if you're exposed to lots of ozone if you're exposed to lots of particles that you're you're sort of uh risk for respiratory ailments goes up but just how much of it is being produced by these lights in a real world environment is still up in the air so in what ways can we use it that's a UV light behind you yes it is yeah so this is a uh a far UV light predominantly quitting out 222 nmet wavelength light which is shown to be very effective in eradicating everything from viruses to bacteria to mold allergens and more PJ Piper is the CEO of a company called far UV technologies that develops all types of UV devices he believes that far UV will become more widely used in tandem with other layers of protection I don't really look at this as displacing HVAC or filtration those are important things they just do different things HVAC is predominantly for climate control it also has a slight benefit of potentially removing the viral load filtration similarly doesn't change the climate control but it's really important for getting rid of inorganic pollutants like Smog or Wildfire smoke or something like that but there's nothing anywhere near as efficient as light as a source um to eradicate the pathogens that might be in the room so pairing UV with other systems could help reduce pollutants too but Barber and other researchers suggest we think about the cost benefit where I think we could run into trouble is if people want to install these lights as a replacement for ventilations a hospital where the risk of infection is very high could probably benefit from this but an old School building on an average day probably less so it might be some time before we start seeing far UV everywhere the odds of a of a next pandemic it it seems to me that it's more a question of when rather than if and so having Technologies like this I think is super important I just want to be careful that we don't get so excited about this kind of technology that we wind up missing something really important look anyone trying to sell you a single miracle cure for anything is likely bending the truth when it comes to fighting disease whether that be the common cold or a full pandemic there's no singular approach we need a toolbox of options from vaccines to masks to chemical disinfectants and in time it's likely that far UV could be one more addition maybe in various forms that we could bring with us to public spaces or installed somewhere above us without us even knowing as an extra invisible layer of protection against those invisible enemies in the air so if you want more info on UV light and germs you can check out unexplainable vox's science podcast about unanswered questions they're working on an episode that goes deeper into everything we don't know about UV light and disease and they'll take you through that original experiment where researchers just decided that kids were better guinea pigs than actual guinea pigs it'll come out next Wednesday February 20th but in the meantime here's a quick preview in 1937 two researchers had a kind of dangerous idea so they figured the perfect place to test it out was in an elementary school on kids on the eve of a massive epidemic

Channel: Vox

Views: 958,542

Keywords: Disinfectant, Germicide, UV, UV Germicide, Vox.com, bacteria, explain, explainer, future perfect, germs, light, pandemic, pandemic response, science, technology, ultraviolet light, viruses, vox, far-uv, uv-c

Id: _iTUaDp-FeI

Length: 7min 44sec (464 seconds)

Published: Thu Feb 15 2024