Yes wonder dust is chemicals - no matter how you pretty it up its just a bunch of chemicals and as for 'detoxifying' I don't believe in it at all so have no faith it does any good. To me that list of chemicals reads like a dye process solution.
Check out pannus to see if it matches corneal issues
http://www.workingdogs.com/doc0087.htm
Wheat is really only a problem food if the dog happens to be allergic to wheat. Same with the other foods. Thing is a dog with immune issues can develop intolerances to almost anything it is regularly exposed to.
The problem item with the skin color changes could be the alum (which is used as a mordant in dying items) or the tannic acid or the copper sulfate all of which are used in dye processes so in combination in the body might result in skin tone changes particularly if there is hair loss and sun exposure in those areas around the eye.
I wouldn't, by the way, consider a raw diet for a dog with immune issues - too many pathogens in the meats and other foods available to us to risk feeding raw to an animal with a compromised system. You might find one of the Wellness products will work for her.
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