Health & Wellness

The Dangers of UV Light Sanitizers

Yes, a UVC sanitizer can kill viruses, but it can also damage your health

By Caitin Finlay


The ultraviolet (UV) light known as UVC will reliably disinfect surfaces, water, and the air, and hospitals, airlines, laboratories, hotels, and many others often use commercially available UVC light devices. Now, with the increased demand for ways to combat the spread of COVID-19, the market is being flooded with inexpensive, unregulated versions of these UVC devices. These new handheld and portable products may seem the perfect defence against COVID-19, but experts warn that these products carry health risks if not used properly.

Within the UV light spectrum, UVC light is the most intense and can alter the DNA and RNA within cells enough that the cells no longer reproduce. This makes UVC light an effective and natural disinfectant or sanitizing method against bacteria and viruses. While the method is used on a commercial scale, it’s regulated and precautions are in place to ensure that it’s used safely.

The UVC lights being sold online and in stores by popular retailers are advertised as useful for sanitizing items such as masks, door handles, baby supplies, food items, car keys, kitchen utensils, cell phones, and more. While many of these new UVC products boast that they quickly kill bacteria and viruses, they carry few or no warnings about the hazards of using such a product or about safety measures. Most also lack instructions on how to use them properly. If used incorrectly, these products can cause harm, and you may not even be aware that it’s happening.

Natural UVC light is absorbed by the Earth’s atmosphere and poses no threat to us. Man-made UVC light, on the other hand, is intense and can be dangerous. Mercury-based UVC lights or ozone-emitting lights have been shown to cause lung damage. Newer LED UVC lights may seem safer but if not used properly, they could damage the eyes and skin within seconds of direct exposure. Skin damage can include burns and even skin-cell mutations. Even more dangerous is that the damage done to the skin or eyes may not appear right away—the user likely wouldn’t be aware of it until symptoms of damage appeared one to two days later.

Richard Webster, a researcher at the CHEO Research Institute in Ottawa, told CBC that he doesn’t recommend the use of handheld UVC lights because most of the claims made about the products haven’t been proved and are likely exaggerated. Many of these products advertise that they kill bacteria and viruses in seconds, but it’s unlikely that a handheld light would be powerful enough to do so.

Similar views were published in a joint statement from the (US) National Electrical Manufacturers Association (NEMA), the American Lighting Association (ALA), and Underwriter Laboratories (a company that tests and certifies the safety of UVC light devices). Todd Straka, the global industry director of lighting at Underwriter Laboratories (UL), spoke with CNET and said, “UL has made a conscious decision not to certify the consumer-facing, portable, handheld wand-type devices due to the inability to manage the risks.”

Straka added, “There are emerging studies to understand the effectiveness of UVC against COVID-19, but in terms of research, there’s a lot still pending on that. So I would caution consumers…if they’re seeing really robust claims about efficacy, to keep in mind that that is still very much in the works.”

Photo: iStock/StudioM1.