DuPont has spent $6 million since 2005 to keep 12,000 residents in the Little Hocking area from drinking a chemical the company uses to make Teflon.

The company has spent $3 million on bottled water and $3 million on a drinking-water filter system that should protect against C8, a chemical that the U.S. Environmental Protection Agency calls a “likely” carcinogen.

Tests of the filters installed at the Little Hocking Water Association show that they remove all detectable levels of C8, DuPont spokeswoman Robin Ollis said yesterday.

The company uses the chemical at its Washington Works across the Ohio River. DuPont has used the chemical for more than 50 years to help make nonstick and stain- and water-resistant coatings for products including pots, pans, carpets and clothes.

DuPont has been paying for the bottled water while it negotiated with the water association over how the filters are installed. After Friday, the company no longer will pay for the bottles.

The company agreed to filter the water at Little Hocking and five other water systems as part of a 2005 lawsuit settlement that could reach $343 million.

Water association officials said they want to see more tests and purge any lingering C8-contaminated water from storage tanks and pipes before they share results with residents.

“We need to establish that the system is working,” said David Altman, a lawyer representing the nonprofit water association. “Our goal is zero C8 in the water.”

The association hopes to send residents a notice or message about the water before Friday, Altman said.

Little Hocking stands in the center of a global debate about C8, which DuPont says poses no threat. The chemical has been found in newborns, dolphins and polar bears.

Nevertheless, the company has said it will phase out use of C8 in its plants by 2015.

Tests of Little Hocking’s four wells in 2006 showed C8 at levels between 1 part per billion to 14 parts per billion. All are above a 0.5 parts-per-billion drinking-water limit the U.S. EPA set in November 2006.

Health studies estimate that 90 percent of U.S. residents have an average 5 parts per billion of C8 in their blood. A 2005 health study of Ohioans living near Washington Works showed median levels of C8 that range from 298 to 369 parts per billion.

In Ohio, DuPont has installed filters in water systems in Little Hocking, Tuppers Plains, Pomeroy and Belpre. In West Virginia, the company installed filters in Lubeck. Ollis said the company also is designing filters for the Mason County Public Service District in West Virginia.

Melinda McDowell, an Ohio University employee who lives in Vincent and whose water comes from Little Hocking, said she plans to start buying bottled water once DuPont stops paying.

“Right now we’re talking about C8,” McDowell said. “But what other things are in the water that’s not on the list, that’s not regulated?”