The problem with this research is that it does not address the issue of how much bromine or any other salts would be absorbed by any porous material after it had been in a cave near the Dead Sea for 2000 years. The human bones from the Qumran cemetery had a high bromine content (Rasmussen et al in Kh Q II, Humbert and Gunneweg (eds)) and Crowfoot when dealing with the linen wrappers over 50 years ago never questioned that they had absorbed Dead Sea salts. Even some of our sherds in Jericho had a flaking of snow-like crystals which were, presumably (as far as I know they were never analysed) salts of some sort. How about testing, for example, the wooden coffins from Ein Gedi for bromine content?Good point.
Background here and here.