A recent study by the Keck School of Medicine at the University of Southern California found that tetrachloroethylene (PCE), a compound used in dry cleaning and found in products such as hand adhesives, stain removers, and stainless steel polish, poses a potential risk to liver health. (Dry cleaning involves cleaning clothes and fabrics without water, using special chemical solvents to remove stains and dirt.)
The study used data from the National Health and Nutrition Examination Survey (NHANES) between 2017 and 2020, and defined liver fibrosis using an ultrasound test to measure liver stiffness. It also took into account other factors such as alcohol use and obesity-related fatty liver disease to confirm the relationship between PCE and liver scarring.
The results showed that approximately 7% of the American adults included in the study had significant levels of this chemical in their blood. Exposure to it, whether through inhaling fumes in workplaces or via freshly laundered clothing, can lead to cirrhosis of the liver, which may progress to liver cancer, liver failure, or death.
The study highlighted two main pathways of exposure:
Working in dry cleaning: where workers breathe air contaminated with PCE all day, leading to chronic and high exposure.
Customers and households: PCE residues can remain on cleaned clothes or in plastic wraps for days, releasing toxins into the air inside the home, car, or closet.
The researchers found that the risk of developing liver fibrosis increased with the level of exposure: the higher the levels of PCE in the body, the greater the likelihood of developing cirrhosis. Among the participants, those with any trace of PCE were more than three times more likely to develop significant liver scarring.
Dr. Brian P. Lee, a liver transplant specialist and lead author of the study, said: "Patients may wonder: How can I develop liver disease if I don't drink alcohol and don't have any chronic illnesses? The answer may be exposure to PCE."
Lee added that the study reveals the important role of environmental factors in liver health, explaining that exposure to PCE can be the reason why some people develop liver disease while others, within the same health and demographic profile, do not. He also pointed out that people with higher incomes tend to be more exposed, given their frequent use of dry cleaning services, while workers in these establishments face the risk of direct exposure for extended periods.
The researchers warned that PCE is an invisible or strongly odorous substance that often enters the body through inhalation, and can also seep into drinking water or be absorbed through the skin when using certain consumer products that contain it.
He assured me that the research represents an important step in understanding the relationship between PCE exposure and liver cirrhosis, and he hopes the findings will help doctors and the public detect the disease early and improve patients' chances of treatment.
The study results were published in the journal Liver International.
