# Does UV water purification cause cancer? [closed]

I found out that a relative is using a machine that performs UV water purification at home (for drinking).

There seems to be a distinct difference from the water that is not purified by it.

Is it possible that this use of UV radiation may lead to cancer in humans?

## closed as off-topic by NotEvans., Todd Minehardt, ron, Geoff Hutchison, getafixDec 31 '16 at 2:14

This question appears to be off-topic. The users who voted to close gave this specific reason:

• "Personal medical questions are off-topic on Chemistry. We can not safely answer questions for your specific situation and you should always consult a doctor for medical advice." – NotEvans., Todd Minehardt, ron, Geoff Hutchison, getafix
If this question can be reworded to fit the rules in the help center, please edit the question.

• No, it does not – getafix Dec 30 '16 at 4:23
• I believe that UV air purifiers make some ozone which might be linked to cancer. Water seems different because by the time you drink it I don't think that it would have radicals. UV is used to sanitize medical equipment and sunlight is putting uv into water all the time. – Joseph Hirsch Dec 30 '16 at 5:24
• Thank you joseph-hirsch for your answer. geafix, In general, UV rays are known to cause skin cancer, so that's why I was confused. – itsols Dec 30 '16 at 5:32
• That's right, but it's not like your water now contains "dissolved" UV rays or something. They are gone. – Ivan Neretin Dec 30 '16 at 6:29
• I'm glad I got the answer to this question. But I'm surprised as to why it is off topic and "personal". I only found out about this due to a relative using it. But I sure believe this applies to the entire human kind (or for that matter all living creatures). So I would like this to remain for the benefit of humans. After all, the tag 'water-treatment' is 100% relevant. – itsols Jan 1 '17 at 7:32

The lamps used for water treatment are usually low pressure mercury vapour lamps. These lamps emit in the UV-C range with a maximum at $\lambda = 254~\mathrm{nm}$.