Michael Hawthorne's Sunday feature does a thorough investigative job in telling a story that goes back decades. The chemical involved, ammonium perfluorooctanoate, known as C8, is used to prevent clumping during the manufacture of Teflon. Removed from the final product that goes to consumers, it is persistent in the environment, accumulates in human blood, and is suspected of causing health problems such as liver damage, reproductive and developmental defects, and cancer. Hawthorne documents exposures to C8 among workers at a West Virginia plant and people who drank from contaminated local water supplies. Hawthorne reports that the manufacturer knew of potential health effects and human exposures for decades but kept the public and the government largely in the dark. C8 is not regulated by EPA. (See: http://www.dispatch.com/reports-story.php?story=dispatch/news/news03/feb03/1639797.html)