Elevated prenatal exposure to fluoride implicated in neurobehavioral problems

Prenatal exposure to fluoride may play a role in neurobehavioral problems, according to researchers in the United States. Ashley Malin and colleagues investigated the association of third-trimester maternal urinary fluoride levels with the neurobehavior of children at the age of three years, analyzing data from 229 mother-child pairs in California. The researchers used the Preschool Child Behavior Checklist to measure total behavior problems, internalizing problems (for instance, anxiety, depression, and somatic complaints), and externalizing problems (for example, aggression).

The researchers report, “We found that women with higher fluoride exposure during pregnancy tended to rate their children higher on overall neurobehavioral problems and internalizing symptoms, including emotional reactivity, anxiety, and somatic complaints by age three years.

Furthermore, each 0.68 mg/L increase in MUFSG [a biomarker for prenatal fluoride exposure] was associated with nearly double the odds of total neurobehavioral problems being in the borderline clinical or clinical range. Women with higher MUFSG during pregnancy also tended to rate their children higher on autism spectrum disorder symptoms.” They add, “The effect sizes observed in this study are sizable considering the relatively low urinary fluoride levels of participants.”

The researchers conclude, “This cohort study found that prenatal fluoride exposure was associated with increased risk for neurobehavioral problems among children residing in the U.S. These findings suggest that there may be a need to establish recommendations for limiting exposure to fluoride from all sources during the prenatal period, a time when the developing brain is known to be especially vulnerable to injury from environmental insults.” They note, too, that recent studies in Canadian and Mexican populations have also shown an association between higher prenatal fluoride exposure and increased neurodevelopmental problems.

Citations

“Maternal urinary fluoride and child neurobehavior at age 36 months,” Ashley J. Malin, Sandrah P. Eckel, Howard Hu, E. Angeles Martinez-Mier, Ixel Hernandez-Castro, Tingyu Yang, Shohreh F. Farzan, Rima Habre, Carrie V. Breton, and Theresa M. Bastain, JAMA Network Open, May 20, 2024 (free online). Address: Ashley J. Malin, PhD, Department of Epidemiology, College of Public Health and Health Professions, University of Florida, 2004 Mowry Rd., Gainesville, FL 32603, ashleymalin@uf