For what it is worth: I've used providone Iodine quite a lot. It is gentle on my skin and releases Iodine over an extended time as it comes out of the solution slowly. The brand I got did not contain any chemicals that are not safe for human consuption, and I did try some internally as well. The providone is designed for painting on the skin and is easy to kleen up if spilled. The stain left on your skin also easily washes off. The stuff is quite inexpensive, and can be purchased almost anywhere. I highly reccomend it for external use. It is quite gentel on the skin, and does not seem to be able to take off warts or moles like stronger tinctures.