Chemical Question: What is stain-resistant carpet treated with?

Most carpets manufactured today are coated with a mixture of stain-resistant "fluorochemicals" sold under familiar brand names like Stainmaster, Scotchgard, and nearly anything advertised as "nonstick" or "water repellant." These coatings are effective at preventing stains, but in some studies have been identified as a likely human carcinogen and associated with developmental harm in newborn lab animals. There are currently many studies underway looking at the specific effects on humans.

This answer comes from the files of the Environmental Working Group, an influential group of scientists, engineers, policy experts and lawyers who work to expose threats to our health and the environment.