MadSci Network: Medicine |
A "black light" is so named because a lot of the radiation it emits is not visible to the human eye, nor detectable as warmth as are infrared rays. The radiation (light, if you will) emitted is ultra-violet, also known as UV. These rays are potentially hazardous if absorbed in large enough quantities. The UV component of sunlight is what gives you a sunburn at the beach and can raise your risk of skin cancer. Not knowing anything in particular about the black light that your son is using as a nightlight, I recommend that he stop using it as such immediately, certainly if he is using it to illuminate the bedroom of his children at all. I repeat: he should stop using it immediately. Such use is totally inappropriate.
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