BEIJING - China is helping U.S. officials investigate reports of contaminated drywall from China after thousands of U.S. homeowners complained the building material made them sick or damaged their houses, a top U.S. safety official said Monday.
Consumer Products Safety Commission Chairman Inez Tenenbaum said that her Chinese counterparts have provided technical help and are working with the United States to determine the cause of the problem.

"We are greatly appreciative," Tenenbaum said after finishing up six days of talks with officials from Beijing's product safety watchdog, the Administration of Quality Supervision Inspection and Quarantine. She didn't give details of the cooperation.

Tenenbaum also called on China's drywall companies "to examine carefully their responsibilities to U.S. consumers who are suffering from problems in their homes and to do what is fair and just in each case if their products are involved."

The costs to homeowners could be in the billions of dollars, according to some estimates, and homeowners have struggled to get help from insurers or relief from lenders.

U.S. construction companies imported the drywall at the height of the housing boom, when building materials were in short supply. The drywall apparently causes a chemical reaction that releases fumes that reek like rotten eggs and grow worse with heat and humidity.

U.S. homeowners blame the drywall for woes such as itchy eyes and skin.

Tests of the drywall by the U.S. Environmental Protection Agency have found sulfur and two organic compounds associated with acrylic paint but did not draw any conclusions about health risks or whether the boards could be damaging wiring in homes.

Since late last year, the agency has received more than 1,300 complaints, with the majority from Florida and Louisiana.