Forever Chemicals May Triple the Risk of Liver Disease in Adolescents, According to New Research
A growing body of research is raising serious concerns about so-called “forever chemicals” and their long-term impact on human health. A new study now adds another troubling piece to that puzzle, suggesting that exposure to certain common PFAS chemicals during adolescence may significantly increase the risk of liver disease, in some cases by nearly three times.
The study was co-led by researchers from the Southern California Superfund Research and Training Program for PFAS Assessment, Remediation and Prevention (ShARP) Center and the University of Hawai‘i, and it focuses on a liver condition known as metabolic dysfunction-associated steatotic liver disease (MASLD). This condition was previously called non-alcoholic fatty liver disease, but the updated name reflects its close ties to metabolic health rather than alcohol use.
Published in the peer-reviewed journal Environmental Research, the findings suggest that PFAS exposure during key developmental years may quietly set the stage for serious liver problems later in life.
What Is MASLD and Why It Matters
MASLD is a chronic condition characterized by fat accumulation in the liver, unrelated to alcohol consumption. While it can develop at any age, it is increasingly being diagnosed in children and adolescents, especially those with obesity or metabolic risk factors.
Estimates suggest that MASLD affects about 10% of children overall, but that number can climb to 40% among children with obesity. The disease is often silent in its early stages, meaning many people don’t realize they have it until damage has already progressed. When symptoms do appear, they may include fatigue, abdominal discomfort, and pain, though many cases remain asymptomatic for years.
Over time, MASLD can raise the risk of type 2 diabetes, cardiovascular disease, advanced liver injury, cirrhosis, and even liver cancer. Because the condition can progress slowly and quietly, identifying early risk factors is a major public-health priority.
PFAS and Their Widespread Presence
PFAS, short for per- and polyfluoroalkyl substances, are a large group of synthetic chemicals that have been used for decades in consumer and industrial products. These include nonstick cookware, water- and stain-repellent fabrics, food packaging, firefighting foams, and certain cleaning products.
They are often called forever chemicals because they do not break down easily in the environment or the human body. Instead, they persist and accumulate over time, leading to long-term exposure even if direct use has stopped.
In the United States, more than 99% of people have detectable levels of PFAS in their blood, and at least one type of PFAS is present in roughly half of U.S. drinking water supplies. This widespread exposure has prompted growing concern among scientists, regulators, and public-health experts.
Inside the Study: Who Was Studied and How
The research analyzed data from 284 adolescents and young adults in Southern California, drawn from two long-running USC-led longitudinal studies. These participants were considered metabolically high-risk, as their parents had either type 2 diabetes or overweight/obesity.
Blood samples were used to measure PFAS concentrations, while MRI scans, considered a gold-standard method, were used to assess liver fat. This is one of the reasons the study stands out: it relied on precise diagnostic tools, rather than indirect markers or self-reported data.
Two specific PFAS chemicals emerged as particularly concerning:
- Perfluorooctanoic acid (PFOA)
- Perfluoroheptanoic acid (PFHpA)
Higher blood levels of these chemicals were associated with a greater likelihood of developing MASLD.
A Nearly Threefold Increase in Risk
One of the most striking findings was the magnitude of the association. Adolescents with double the amount of PFOA in their blood were found to be nearly three times more likely to have MASLD compared to those with lower levels.
The risk did not exist in isolation. It was influenced by age, genetics, and lifestyle factors, showing that PFAS exposure interacts with other biological and environmental variables rather than acting alone.
MASLD also became more common as adolescents grew older, reinforcing the idea that puberty and early adulthood may represent a particularly vulnerable window for environmental exposures.
Genetics and Lifestyle Make a Difference
The researchers also examined how PFAS exposure interacts with known genetic and behavioral risk factors. One genetic variant, known as PNPLA3 GG, is already well-established as a contributor to liver fat accumulation. Adolescents who carried this variant and had higher PFAS levels faced an even greater risk of MASLD.
Lifestyle factors played a role as well. Among young adults, smoking appeared to amplify PFAS-related liver effects, suggesting that chemical exposure and personal habits may compound one another over time.
Taken together, these findings point to a complex interaction between environment, genes, and behavior, shaping who is most vulnerable to liver disease.
Why Adolescence Is a Critical Window
Adolescence is a period of rapid growth, hormonal changes, and metabolic development, making the body especially sensitive to environmental stressors. Researchers emphasize that liver fat accumulation during these years may have long-lasting consequences.
Once metabolic dysfunction begins early in life, it can create a trajectory toward lifelong liver and metabolic health challenges. This is why reducing PFAS exposure during childhood and adolescence could offer meaningful long-term benefits.
The study builds on earlier research showing that PFHpA is linked to more severe liver damage, including inflammation and fibrosis, in adolescents undergoing bariatric surgery. Together, these findings strengthen the case that PFAS exposure is not just a biochemical concern, but one that translates into real-world disease outcomes.
Broader Health Concerns Linked to PFAS
Beyond liver disease, PFAS exposure has been associated with a wide range of health issues, including certain cancers, immune system disruption, hormonal interference, and developmental effects. Adolescents may be especially vulnerable because their organs and regulatory systems are still developing.
This growing evidence has fueled calls for stricter regulation, improved water filtration, and greater public awareness of PFAS sources. While individual exposure can be difficult to eliminate entirely, understanding the risks is a crucial first step.
What This Research Adds to the Conversation
This study is among the first to examine PFAS and MASLD in children using gold-standard diagnostic criteria, and the first to explore how genetics and lifestyle factors modify PFAS-related risk in young people.
Rather than pointing to a single cause, the findings highlight how environmental chemicals, inherited traits, and everyday behaviors work together to influence disease risk across different life stages.
For public-health experts, the message is clear: early prevention matters, and reducing PFAS exposure during adolescence could help prevent serious liver disease later on.
Research paper:
https://doi.org/10.1016/j.envres.2025.123320
