I believe that, once we rethink the job of the kidneys and just what urine really is, the next question must be if there are any circumstances where UT should NOT be used.
Round and round my mind goes, and I've come to the conclusion that the body is dealing with existing toxins anyway, and the urine already contains all the good things that the body has created to deal with these existing toxins, so why not re-ingest them and let the body sort out what's needed? There are already several elimination systems working on our behalf, anyway. The proof is that we are still breathing!
The elimination systems are the bowels, the skin, and the lungs, as far as I know. The kidneys are NOT 'toxin elimination' organs; they are the BALANCERS of all that is currently circulating, I am amazed to learn.
The spleen and the liver are the sorters of all we take in, including toxins, I believe. (Plus the liver does all kinds of other jobs.)
Of course, it is wise not to add any further toxins to the body, so we need to learn what those are and eliminate them from our lives, but the body is already hard at work on those already in there, with an exact precision that is far beyond the understanding of any brain that will ever exist! IMHO