A chemical called perfluooctane sulfate (PFOS) has been linked to the most common type of liver cancer, a new study indicates.
PFOS is used in a wide range of consumer and industrial products, and are referred to as “forever chemicals” because they break down very slowly and accumulate both in the environment and in human tissue.
Researchers at the University of Southern California’s Keck School of Medicine combed through human blood and tissue samples gathered as part of a large-scale study. They then compared samples from 50 liver cancer patients with 50 others who didn’t develop cancer.
Researchers found several types of poly fluoroalkyl substances (PFAS) the family of chemicals to which PFOS belongs — in the blood samples of patients taken before their liver cancer diagnosis.
The strongest link was between PFOS and liver cancer. People with PFOS levels in the top 10% were 4.5 times more likely to develop liver cancer than those with the lowest levels, researchers found. They also found evidence that PFOS disrupts normal metabolic processes in the liver, causing more fat to accumulate in the organ. Fatty liver disease is known to increase the risk of liver cancer, and is expected to affect 30% of U.S. adults by 2030.
Some manufacturers have phased out the use of PFOS and other types of PFOA, but because the chemicals are long-lasting, they can be found in the blood of more than 98% of adults in the United States, researchers said.
“This builds on the existing research, but takes it one step further,” Jesse Goodrich, a postdoctoral scholar in the department of population and public health sciences at Keck, said in a university news release. “Liver cancer is one of the most serious endpoints in liver disease and this is the first study in humans to show that PFAS are associated with this disease.”
Parvathy Sukumaran 
