Um, could you please use your words?
I would discount carbon disulfide, CS2, as the smell you report. Carbon disulfide does not smell bad. There are many other more common sulfur based contaminants that stench, and so will mask the sweeter smell of CS2.I am investigating these strange sewer like fumes to which I react. Is there a possibility that I am reacting to a combination of H2S and CH4?