Elevated levels of lithium in drinking water used by pregnant mothers may impact a key molecular pathway involved in neurodevelopment and increase the risk of offspring developing autism spectrum disorder, according to a study by UCLA Health researchers.
The findings, based on Danish data, indicate a need for further research in other regions and populations, as human activities like lithium battery usage and landfill disposal may lead to groundwater contamination and higher lithium levels.
The study has been published in the Journal of American Medical Association (JAMA) Paediatrics.
Lead study author Beate Ritz, a UCLA Health neurology professor, emphasised the need for thorough examination of any drinking water contaminants that may impact the developing human brain.
While lithium is commonly used to treat depression and bipolar disorders, its safety for pregnant women is a subject of debate due to potential risks like miscarriage and cardiac anomalies in new-borns.
Ritz's research has shown that lithium, a naturally occurring metal found in water, may affect a crucial molecular pathway related to neurodevelopment and autism.
The study's lead author, Zeyan Liew, an assistant professor at Yale University School of Public Health, explained that their research builds on prior findings from Denmark's medical registry data linking chronic, low-dose lithium ingestion from drinking water to neuropsychiatric disorders in adulthood.
Liew and Danish researchers examined lithium levels in 151 public waterworks and a national psychiatric database to identify children born between 1997 and 2013. Comparing 12,799 children diagnosed with autism to 63,681 unaffected peers, the team found that autism risk correlated with lithium levels.
The study revealed that when the lithium levels were divided into quartiles, the second and third quartiles showed a 24-26 per cent increased risk of autism, while the highest quartile had a 46 per cent higher risk compared to the lowest.
Additionally, the association was slightly stronger for those residing in urban areas versus smaller towns or rural areas.
(With inputs from PTI)