People are adding PFAS, also known as "forever chemicals," to wastewater without knowing it.
A study published in Environmental Science & Technology Letters says toilet paper should be considered a "potentially" major source of PFAS entering wastewater treatment systems.
Researchers came to that conclusion after testing toilet paper and wastewater sludge for PFAS. They found fluorotelomer phosphate diester, a type of "forever chemical," in both toilet paper and wastewater sludge.
Researchers drew samples from all over the world, including the U.S., Chile, South Africa and the U.K. While the presence of PFAS were detected globally, the amount varied on how different populations use toilet paper. In the U.S., it's customary to flush toilet paper. Some parts of the world throw toilet paper in the trash.
Studies have linked exposure to PFAS to adverse health effects. However, the Centers for Disease Control and Prevention says it's still investigating how exposure to PFAS can be harmful.
The CDC notes that PFAS are in food and the environment, making it unlikely to eliminate exposure entirely.