Apparently hundreds of homes getting new wallboard in 2005 and 2006 were dealt a rotten batch of wallboard, as in rotten eggs. The Chinese-originated wall board apparently vents sulphur compounds. That in turn does nasty things to pipes, air conditioners and humans. So far the problem has only been found in the Southeastern U.S.
When they reapir those places, I can only they buy domestic next time. Perhaps get some of that recycled CO2 from Serious Materials.