This is pretty interesting (the BR cancer thing). I don't know much about this stuff, but I read Wikipedia and WHO articles and concluded that (correct me if I'm wrong here) the wavelength of a laser is the sole factor which determines if it is ionizing or not.
Now anything in the short end of the spectrum (GAMMA, XRAY, UV) is ionizing... apparently UV is anything from 10nm to 400nm.... now if diodes can (as was said) put out +-10nm, then why couldn't a BR putting out 395nm be damaging?
UV by definition is not visible, so I suppose if a BR diode decided to put out 395nm you wouldn't see anything... but hypothetically if someone was exposed to this non stop for a year say... is there any fundamental reason why it couldn't cause DNA mutation?