Is this UV toothbrush sterilizer safe?

Thread Starter

pancake95

Joined Feb 13, 2019
20
Hello all, my familly member just bought without my knowledge a UV toothbrush sterilizer. The sterilizer is chinese ofcourse and looks something like that https://www.amazon.com/PURETTA-Toot...t+toothbrush+sanitizer&qid=1605373604&sr=8-56, but it just does not have the branding on it. On the box is written only UV toothbrush dispencer and sterilizer. There is no description of the UV light used or any certification that will calm me down about the safety of this device. Inside the box is the item and description of the many functions it provides(one of which is movement detection up to 1 meter in order to turn off the UV light). My question is should we use it? I am also not completely sure if it uses UV light at all, because it costed around 5$ to my familly member. What should we do? Sorry if the question is not for this category.
 

Marc Sugrue

Joined Jan 19, 2018
217
I'd be more concerned of the bristels in the toothbrush going brittle after a few weeks exposure to true UV and having a mouthful of fibres as they break off. For $5 though my guess is that its using a Blue LED and at best a 405nm LED which is not in the UV region and is safe but it will have NO germicidal impact. If you turn it on and you can see the light then its not Germicidal or Bacterial lighting as this type of light is invisble to the eye.
 
Last edited:

Thread Starter

pancake95

Joined Feb 13, 2019
20
Now my familly member said it was 10$, not 5$. But I think it is still cheap to be UV. My concern is not the bristels of the toothbrushes, but our health. Although it says it turns on after 2 hours of not detecting movement. What if the movement detection sensor goes bad and it turns on the UV. It can damage the skin and the eyes or the lids of the toothbrushes are not that open in order the UV light to get to us?
 

Marc Sugrue

Joined Jan 19, 2018
217
Now my familly member said it was 10$, not 5$. But I think it is still cheap to be UV. My concern is not the bristels of the toothbrushes, but our health. Although it says it turns on after 2 hours of not detecting movement. What if the movement detection sensor goes bad and it turns on the UV. It can damage the skin and the eyes or the lids of the toothbrushes are not that open in order the UV light to get to us?
Only way to be sure is measure it with a spectroradiometer or contact the manufacturer to find out the wavelength. The reality is though that any likely exposure is probably short and the dose of UV very small. So your risk assessment will needs to be based on that. The Puretta uses a 254nm LED which is TRUE UV-C but as its invisible should be accompanied with a visible LED to notify its on. If this is not the case then to be honest they shouldn't be making it in the first place

https://www.kickstarter.com/project...on: Puretta uses a,and peace of mind everyday.
 
Last edited:

dl324

Joined Mar 30, 2015
13,082
It can damage the skin and the eyes or the lids of the toothbrushes are not that open in order the UV light to get to us?
UVC isn't dangerous to eyes or skin. UVA and UVB are.

Just don't put eyes or skin close to it when it's in use. If it isn't actually UV, you won't get any sterilizing benefit. If there is UV, you'll likely smell ozone when it has been operating. I get that from my EPROM erasers.
 

Marc Sugrue

Joined Jan 19, 2018
217
UVC isn't dangerous to eyes or skin. UVA and UVB are.

Just don't put eyes or skin close to it when it's in use. If it isn't actually UV, you won't get any sterilizing benefit. If there is UV, you'll likely smell ozone when it has been operating. I get that from my EPROM erasers.
I think your VERY mistaken, UV-C is extremely dangerous, it can cause cancer. There is a narrow window around 222nm which has been scientifically proven to be "potentially safe" but hasn't been approved by any safety organisation yet. Only safe application for UV-C current is in a box.
 

dl324

Joined Mar 30, 2015
13,082
I think your VERY mistaken, UV-C is extremely dangerous, it can cause cancer. There is a narrow window around 222nm which has been scientifically proven to be "potentially safe" but hasn't been approved by any safety organisation yet. Only safe application for UV-C current is in a box.
Well, if you want to get into a pi**ing contest about it, 100-200nm wavelengths are strongly absorbed by atmospheric oxygen. So now we're near your 222nm number...
 
254 nm light works. Plastics typically attenuate UV light. UV light degrades some plastics.
There is a time-exposure-distance-organism effectiveness.

UV is used in HVAC systems.

I have an electronic air cleaner and UV light. The manufacturer suggested a reflector to keep the UV away from plastic parts of the air cleaner and to use another on the evaporator.

Previously, I considered the UV lights were not necessary with an electronic air cleaner,. I think that's the wrong assumption in the COVID-19 ERA.

Regular UV lamps (usually mercury based) lose their output over time. We had a 1000W arc lamp source (It put out some UV) that had a lifetime of 1000 hours. The spectra changed over time.
Changing that lamp was an ordeal.
 

Marc Sugrue

Joined Jan 19, 2018
217
Well, if you want to get into a pi**ing contest about it, 100-200nm wavelengths are strongly absorbed by atmospheric oxygen. So now we're near your 222nm number...
Hi, i think your point is the light won’t go far in air. I agree

222nm is only 22nm above the 200nm band you quote. All i said was UV-C as a band is not safe and only 222nm peak wavelength (narrow band) had been scientifically proven to be potentially safe (to human skin & eyes). Even at this wavelength the safety is still not absolutely proven but the likes of Boeing have moved forward on it but there are already lawsuits in the US as to how 'Safe' or effective it is.

https://boeing.mediaroom.com/2020-0...iolet-Wand-to-Healthe-Inc-to-Counter-COVID-19

https://www.classaction.org/blog/do...-kill-99.99-percent-of-viruses-germs-bacteria

https://faruv.com/

The final link shows the PPE you have to wear for the potentially 'safe' 222nm the polycarbonate visor completely aborbs UVC to prevent it getting to the skin. This is protection for Boeing and Far UV as its not scientifically proven to be safe but it does help kill viruses

https://faruv.com/boeing-and-far-uv...ng-agreement-for-ultraviolet-wand-technology/

Sorry if i upset you that wasn't the intention. Poor choice of grammer and use of capitals.

Sorry
 
Last edited:

MisterBill2

Joined Jan 23, 2018
9,235
Even if the light is UVc the exposure times would he short and the power level is quite low and the fear level is very high because of the lack of understanding. So the important precaution is to avoid long exposures and not bring their faces right next to the device.
 

BobTPH

Joined Jun 5, 2013
3,653
I suspect an hour in the sun is more dangerous than the time you might spend in the bathroom with a very low power UV source of a toothbrush sterilizer. Wear sunscreen and stop worrying.

Bob
 

MisterBill2

Joined Jan 23, 2018
9,235
I think your VERY mistaken, UV-C is extremely dangerous, it can cause cancer. There is a narrow window around 222nm which has been scientifically proven to be "potentially safe" but hasn't been approved by any safety organisation yet. Only safe application for UV-C current is in a box.
How much of that dangerous UV is going to be escaping from the enclosure illuminated by one low-power LED aimed in another direction? My power saw is dangerous, but it only does harm if one puts a part into harms way. Mains voltage is very dangerous, and so folks must avoid contact with it.
 

Marc Sugrue

Joined Jan 19, 2018
217
How much of that dangerous UV is going to be escaping from the enclosure illuminated by one low-power LED aimed in another direction? My power saw is dangerous, but it only does harm if one puts a part into harms way. Mains voltage is very dangerous, and so folks must avoid contact with it.
In relation to the product on the original post probably not a lot.

My post was more in relation to the statement that UV-C is safe which, as this is a Forum used by both Amateur and Professionals alike i felt should be corrected as it Hazardous and not safe. No Hobbiest should be lighting them up on a work bench in plane view without the correct PPE.

A power saw by its very nature is dangerous so by design they contain safety interlocks and require the use of PPE for risks which can't be mitigated. Mains voltage is dangerous so by design you place it in a suitable enclosure (unless of course your working on it) but you also then use suitable PPE.

UV-C in general is very much like mains, its an invisible hazard, lower amounts is lower risk, but all current UV-C products are pre-regulation so their hazard levels are still undefined. Looking at these LEDs directly have the potential to give a lot of the symptoms of Looking at a Welding arc
https://www.ccohs.ca/oshanswers/safety_haz/welding/eyes.html#:~:text=Certain types of UV radiation,the front of the eye.
 
Last edited:

MisterBill2

Joined Jan 23, 2018
9,235
The safety interlocks on my power saws made them unusable. Safe, but not usable. need I say more. Many years have gone by and lots of cutting done and not one injury or close call, in spite of those safety features not functioning as intended.
 
Top