Estimates of >60,000 homes in Florida are potentially affected

"The problematic drywall, imported between 2004 and 2006, appears to be related to the presence of iron disulfide (FeS2 pyrite). Hydrogen sulfide (H2S), carbonyl sulfide, sulfur dioxide (SO2), and carbon disulfide (CS2) are also suspected as culprit.

There are also reports of Chinese drywall that was kept on barges at sea for months awaiting permission for importation to the USA. This drywall appears to have a higher than typical density and also a higher propensity to off-gas sulfur compounds."