1. Tile adhesive (mortar) and grout are basically sand mixed with lime and other drying agents. These ingredients usually are not incredibly toxic and their effects should fade quickly. The reason I ask, is are you sure the encephalitis issues are directly from the mortar?
Just curious, I have worked with tile mortar for years and normally, the only effect is dry/cracked hands (especially with pre-mixed mortar, there is no dust inhalation issue). I would authentically think that the encephalitis issue could be from something else. Manufacturers don't make poison mortar because the installers would all die quickly, and they would go out of business.
2. Search the internet to see if there's any information about the various 'agents' and additives they add to grout and adhesives. Tilers cut tiles with special saws and cutters, and must therefore be exposed to all kinds of vapour and chemicals. I would start by scanning and treating with the metal and chemical treatments (maybe the Morgellons and Lyme 1 and 2). There is some evidence that fungus found in bathrooms and old tiles and grouting contain a fungus that can possible lead to this. So scan and treat fungus also.
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