Sounds like a "pile on" day for the idea?
But I do have to agree that the idea may have some flaws. As I see it, you will not be exposed long enough to do much harm but then I doubt there will be much good, either. Water is difficult for the UV to penetrate very far. I using UV to make "found water " safe to drink, the water has to be exposed to the bulb very closely and for something like a minute. Murky water will totally block the UV so the water has to be clear to get it to penetrate even an inch. I doubt that enough will penetrate for long enough for much progress.
But then to avoid totally bumming the idea, I do see a good start on a DIY light system that can be very easy to adapt to different uses by changing bulb size and type.