Harmful chemicals found in consumer and industrial products are contributing to rising rates of liver disease in children, a new study suggests.
The study, by researchers at Mount Sinai and published Wednesday in JAMA Network Open, takes the first comprehensive look at prenatal exposure to chemicals that disrupt the endocrine system and the recent rising rates of non-alcoholic fatty liver disease (NAFLD) in children. It found that children who were highly exposed to such chemicals during pregnancy had elevated levels of biomarkers that indicate risk for liver disease.
Endocrine-disrupting chemicals are a type of environmental pollutant found in cookware, food packaging, furniture, infant products, pesticides and more that interfere with the endocrine system, which produces and releases hormones. They include the group of chemicals known as PFAS, also called “forever chemicals” because of how long they linger in the environment.
Rates of pediatric NAFLD have been steadily increasing, with 36 kids out of every 100,000 having the disease in 2009 compared to 58.2 per 100,000 in 2018, according to research published in Pediatrics in 2020. The American Liver Foundation currently estimates 10% of all U.S. children have NAFLD, and 38% of obese American kids do.
"Children, who will have the longest time course of disease, are at particular risk of complications and poor prognosis, including the need for liver transplant in adulthood," the foundation noted. A press release about the study also stressed that NAFLD in kids can lead to chronic liver disease and liver cancer in adulthood.
The Mount Sinai researchers conducted the study by first measuring levels of 45 endocrine-disrupting chemicals, including PFAS, in the blood or urine of 1,108 pregnant women between 2003 and 2010. When the children were 6 to 11 years old, researchers measured the levels of biomarkers in their blood that indicate risk of liver disease. Higher levels of exposure to the chemicals in utero was associated with elevated biomarkers. The study also found that transmission of such chemicals occurred between mother and baby through the placenta before birth and through breastmilk after birth.
“We are all daily exposed to these chemicals through the food we eat, the water we drink and the use of consumer products,” Dr. Damaskini Valvi, assistant professor at the Icahn School of Medicine at Mount Sinai, told TODAY. "This is a serious public health problem."
"These findings show that prenatal exposure to endocrine-disrupting chemicals is a risk factor for pediatric non-alcoholic fatty liver disease,” she added.
While virtually everyone is exposed to endocrine-disrupting chemicals at some point in their lives, early exposure — including in the womb — increases a child’s risk of NAFLD, according to Valvi.
Obesity and genetics also contribute to a child's risk of developing NAFLD, but these factors don't explain how fast rates of the disease have increased, Dr. Robert Wright, study co-author and co-director of the Institute for Exposomic Research at Icahn Mount Sinai, told TODAY.
“Genetics can’t explain the epidemic rise in disease over just 20 to 30 years. It takes multiple generations for genes to change the rate of a disease, and only something in the environment can explain changes that happen this fast. ... Never before have we seen this much liver disease in children,” he said, noting that the chemicals we eat or absorb “play a big role in what is happening.”
What can parents do about prenatal chemical exposure
One way parents-to-be can reduce their developing fetus's exposure to endocrine-disrupting chemicals is to avoid the use of products that contain them, such as plastic containers, bottles, canned food and beverages, and processed foods, Valvi said. “Consume fresh and organic foods whenever possible,” she advised.
Valvi did not provide specific brands of products to avoid, but the American Academy of Pediatrics has advice on reducing PFAS exposure. And the Centers for Disease Control and Prevention has resources on PFAS and PBDEs, another group of chemicals the study looked at.
Wright also suggested that young children especially have limited sugar intake and exercise regularly to combat obesity. “When I was a resident in the '90s, obesity was rare in children,” he said. “(It) now affects one in every five children and adolescents in the U.S.” Even though the research underscores how chemicals may increase risk of liver disease in children, “the biggest contributor to pediatric liver disease remains the epidemic of child obesity," he said.
Valvi and Wright are hopeful their study will help policy makers recognize the importance of banning endocrine-disrupting chemicals from consumer products and requiring companies to disclose exactly which chemicals are used in products and packaging so consumers can make informed decisions for their health. “By understanding the environmental factors that accelerate fatty liver disease, we can reduce people’s risk by giving them actionable information,” Wright said.
In the meantime, Valvi stressed more studies like theirs are needed "to understand how environmental chemical exposures may interact with our genes, nutritional and social factors in the development of pediatric liver disease."