Higher concentrations of lithium in drinking water in pregnant women carry significant possibilities of increasing the risk of autism in children, according to a new study.
The study, published in JAMA Pediatrics on April 3, investigated whether maternal exposure to lithium in drinking water is linked to autism spectrum disorder (ASD) in offspring. Conducted in Denmark, the study analyzed 8,842 children diagnosed with ASD born between 2000 and 2013. Lithium levels in water were categorized into four groups, with the first quartile representing the lowest lithium level and the subsequent quartiles with higher lithium concentrations.
The researchers found that high lithium levels in the second and third quartiles were associated with a 24-26% higher risk of autism than in the first quartile. The risk in the fourth quartile was 46% higher.
“Estimated prenatal maternal exposure to lithium from natural drinking water sources in Denmark has been associated with an increased risk of ASD in the offspring. This study suggests that lithium naturally present in drinking water may be a novel factor environmental risk for the development of ASDs that requires further investigation,” the study found.
Lithium, a natural trace element, is known to have mood-stabilizing effects. The element has been linked to heart defects in newborns as well as miscarriages.
Lithium usually ends up in drinking water due to the weathering of underground minerals. The level of the element in water is considered moderate to low in Denmark.
Lithium contaminated water
Beate Ritz, the study’s lead author and professor of neurology at UCLA’s David Geffen School of Medicine, decided to look into the potential links between lithium and autism risk after discovering that it There was little research on how the element affects human brain development. .
“Any drinking water contaminant that may affect human brain development deserves careful consideration,” she said, according to an April 3 news release.
“In the future, anthropogenic sources of lithium in water may become more prevalent due to the use and disposal of lithium batteries in landfills with the potential for groundwater contamination.”
Zeyan Liew, the study’s first author and assistant professor of epidemiology at Yale University’s School of Public Health, pointed out that previous research from Denmark had already shown that lithium ingestion by the alcohol consumption could affect the onset of neuropsychiatric disorders in adulthood. troubles.
The recent study also found that high levels of lithium continued to pose a higher risk for autism diagnosis, even when the data was split by subtypes of the disorder.
The link between lithium levels and autism risk was found to be slightly higher in people living in urban areas than in rural areas and small towns.
Autism in the United States, genetic links
The JAMA study comes as rates of autism in children have risen in the United States, according to the latest data from the United States Centers for Disease Control and Prevention (CDC).
In a study released last month, the CDC estimated that 1 in 36, or 2.8 percent, of 8-year-olds nationwide has autism. This is up from 1 in 44 in 2018 and 1 in 150 in 2002. Boys were much more likely to develop autism than girls.
The study was conducted among 11 communities that are part of a CDC-funded program called the Autism and Developmental Disabilities Monitoring Network. Another national estimate puts autism rates among children ages 3-17 at 2.9%.
In an October 2022 study published in the International Journal of Health Geographics, researchers at the University of Utah proposed that ancestry contributes to increased autism risk, particularly where and when grandparents and their children were born.
Nutritional access for paternal grandparents during childhood has been shown to have a direct impact on the health outcomes of grandchildren.
“Looking at families and where and when they lived helped us detect groups of individuals who appear to have a higher subsequent risk of autism among their descendants,” said lead author and environmental epidemiologist James VanDerslice of the University of Utah.