An unregulated chemical used in furniture, carpet and Teflon could be a serious health risk to the public, prompting the Environmental Protection Agency this week to launch an in-depth assessment to determine its safety...Last week, the Environmental Working Group, an advocacy organization, alleged that DuPont withheld from the government an internal study linking C8 to birth defects in two of seven children born to DuPont employees in the early 1980s