After initially exceeding not-yet-enforced drinking water limits for the most common types of PFAS chemicals, Tennessee American Water reported last year that it did not detect the substances in the Chattanooga water supply.
Under new standards first introduced by the Biden administration in 2022, the Environmental Protection Agency now considers four parts per trillion an unacceptable level for certain types of per- and polyfluoroalkyl substances, or PFAS, in drinking water.
One part per trillion is equivalent to one drop of water in 35 junior size Olympic swimming pools.
Also called “forever chemicals,” PFAS are a human-made group of compounds used for decades in firefighting foam, fast food wrappers, cookware, carpets and other commercial products. PFAS are known for their heat- and stain-resistant properties, and they don’t break down naturally in the environment, meaning they can accumulate in animals through food or water.
Studies indicate the chemicals may cause developmental delays in children, increase the risk of certain cancers and reduce the body’s ability to fight infections, according to the EPA.