Research Links Common Chemicals to Higher Liver Disease Risk
Recent findings suggest that exposure to everyday chemicals, particularly those used in dry cleaning and certain consumer products, significantly increases the risk of serious liver diseases. Specifically, tetrachloroethylene (PCE), also found in some adhesives and stainless steel polishes, appears to be linked to a three-fold increased risk of developing severe liver fibrosis among U.S. adults, according to a study conducted by the Keck School of Medicine at the University of Southern California.
Liver fibrosis involves a buildup of scar tissue that can lead to liver cancer, failure, or even death, as noted in a press release.
Study Insights
The researchers also noted a dose-response relationship; basically, higher levels of PCE exposure correlated with a greater likelihood of liver fibrosis. Their study, published in the journal Liver International, analyzed data from the National Health and Nutrition Examination Survey (NHANES), reflecting a representative slice of the U.S. population.
To assess PCE exposure, the team examined blood samples from 1,614 adults aged 20 and above, collected between 2017 and 2020. They discovered that about 7% of these individuals had detectable levels of the chemical. Those with PCE in their blood were three times more likely to exhibit significant liver fibrosis compared to those without.
“We were caught off guard by how many people showed detectable PCE in their blood and the strong link to liver scarring,” shared Brian P. Lee, MD, a hepatologist at Keck Medicine. “Most previous studies focused on occupational exposure, so people might be surprised to learn they could be affected even if they don’t directly handle PCE.”
Interestingly, higher-income individuals are reportedly at greater risk for PCE exposure, largely because they tend to use dry cleaning services more frequently. However, those working in dry cleaning facilities are also vulnerable due to their continuous exposure.
Additional Factors and Concerns
Other health risks, including alcohol consumption and obesity, didn’t seem to worsen the impact of PCE. Lee pointed out that patients often wonder how they developed liver disease despite not engaging in typical risk behaviors like alcohol use. The answer, he suggested, might lie in PCE exposure.
Long-term exposure to PCE has been associated with various health issues beyond liver damage, such as neurological disorders and mood changes. Short-term exposure can result in respiratory irritation and other neurological symptoms.
Pregnant women and children are notably more susceptible to developmental impacts from these chemicals. The U.S. Environmental Protection Agency (EPA) has classified PCE under conditions of use as presenting an “unreasonable risk.”
In response to these concerns, the EPA issued regulations in December 2024, restricting the use of PCE in various applications, including dry cleaning. Although a ten-year phaseout of consumer PCE was announced, current discussions are reconsidering that ban.
Study Limitations and Future Research
The study does have limitations; it was cross-sectional, meaning it only captured PCE levels at a single moment in time. As a result, establishing a direct cause-and-effect relationship between PCE exposure and liver fibrosis is challenging. Moreover, findings may not extend to populations outside the United States.
Lee added that further research is essential to ascertain the role of environmental toxins in liver disease risk, emphasizing that other harmful toxins likely exist.
This research was supported by the National Institute on Alcohol Abuse and Alcoholism and the National Institutes of Health. A clearer understanding of these issues may help improve patient outcomes, especially as liver disease rates are climbing alarmingly across the country.
