@dannybex, do you know if magnesium sulphate provides the sulphate that someone would need if they can't handle sulfur?
Yes, that's true. That may be a partial option to increase sulfate, but that still wouldn't address a sulfur, sulfite problem. It might help increase sulfate levels though, which is good.
Still,
molybdenum is an absolutely essential trace element that is part of four different enzymes. Sulfite oxidase, that degrades sulfur into sulfite and then sulfate, plus xanthine oxidase, which is required for purine breakdown and the metabolism of drugs and toxins, aldehyde oxidase -- also involved w/drug/toxin metabolism, and which also helps turn aldehydes from candida, alcohol, and many chemicals (think MCS) into acetic acid.
It's possible to get it from foods, so perhaps that's another option.