In late 2008 and 2009, Florida homeowners began to notice foul sulfur odors in their homes. Upon further inspection, they discovered the odors were emanating from their drywall, a material used to construct interior walls. Soon, homeowners in other states noticed the odors as well as reports of problems with their air conditioners, corroded electrical wiring, and browning of their silverware. Many complained of sinus problems, headaches and bloody noses.
Inspectors and researchers traced the drywall to Chinese imports and to gypsum mines in China. Since many of the complaints began to surface when the U.S. housing market began to collapse, Chinese officials suggested that domestic drywall manufacturers were seizing upon the reports to denigrate their product and to lay blame for suffering domestic sales on the imported products.