The subpoena from the U.S. District Court in Washington, D.C., calls for documents previously handed over to the Environmental Protection Agency (search) as part of its investigation into the possible dangers of perfluorooctanoic acid (search), or PFOA, and its salts.
In February, the chemical manufacturer agreed to pay $107.6 million to settle a class-action lawsuit from West Virginia residents who charged that the chemical contaminated their water supplies. The funds include money to be used for a study to determine if PFOA makes people sick.
DuPont has drastically reduced its emissions of the chemical, also called C8, since the suit was filed in 2001.
The EPA has said PFOA could pose "a potential risk of developmental and other adverse effects" and is seeking millions of dollars in fines from the company for alleged violations of environmental regulations and failure to report information about the chemical.
PFOA is used to coat cookware surfaces, but is also included in products such as car fuel systems, clothing, firefighting foam and phone cables. DuPont has maintained that the chemical is harmless.