I just developed a test for iodine, bromine, selenium and arsenic levels in urine by inductively coupled plasma mass spectrometry that will be available within the next couple of months. Of over 500 previous samples (from all over the US and World) I ran to develop reference ranges, NONE had bromine levels over 10mg/L. These samples include those who take high supplemental levels of iodine. There was NO significant difference. "Bromism" is typically seen at levels >500 mg/L in urine. It is hard to not question whether bromine is causing the "detox"
Also, I sent two identical urine samples to two different labs. One running bromine by ICP-MS and the other Ion Electrode. The result from the ion-electrode test was 10x higher. ICP-MS is the gold standard in elemental testing and the ion-electrode is subject to interferences (high iodine). 6mg/L and 60mg/L is a huge difference. Could also be a problem with standard creation and lack of available bromine controls/calibrators (there is only one currently available)
One interesting study I just ran did show high levels of bromine (~20mg/L) in a very specific population of people. It was the first that I have seen high levels of bromine in urine, and looks like it is a result of consuming the same diet. Once it is published, I can provide more details.
There are many positive benefits of Iodine
supplementation. At what level... I think more research needs to be done.