The effects of H2S are often misunderstood. Since it's recognition as the third cell signaling molecule approximately 10 years ago by Mark Roth Ph.D. much research has begun. Several journal entries may be seen at http://www.facebook.com/pages/Soothing-Sulfur-Spas/119151721441137 regarding the beneficial research being conducted, and anticipated uses, of hydrogen sulfide. Since this area of research is not well known, articles claiming only detrimental effects of H2S may be suspect of inaccuracy.
I believe the information being referred to by Dr. Ramos is research conducted by Kenny De Meirleir M.D., PhD, Vrije Universiteit Brussel, Brussel, Belgium. In previous articles Dr. De Meirleir has recognized the importance of hydrogen sulfide for proper cellular function. The article refers to situations where levels of H2S exceed the normal levels required for good health and began to cause toxicity. Further information may be seen in "CFS Research" at the following web address: http://www.cfsresearch.org/cfs/xmrv/systemic-immune-activation-xmrv.htm