The Environmental Protection Agency has found suspect materials in Chinese-made drywall, adding weight to fears that the foreign drywall may be causing corrosion in homes and possibly sickening people in several states.

EPA tested Chinese-made wallboard in two Florida homes and discovered sulfur and two organic compounds associated with acrylic paint, the report said. Those chemicals were not found in four samples of American-made drywall, the EPA report said.

Several federal and state agencies are investigating complaints that Chinese-made drywall is corroding copper pipes, blackening jewelry and silverware and causing health problems.