The power transformer had to pass a leakage test (electricity, not water!) in order to get a safety listing. That's one hazard taken care of. I see very little real risk here - not that's it's a good idea to do what she's doing. Maybe a barely noticeable tingle from the 16 volts. I'm not vollunteering to put this to the test or anything... With a GFI I'd have no concerns whatsoever, aside from ruining a laptop.
