The Water is Poisoned (Part 2)

The first U.S. based Cohort Study of the effect of Prenatal Fluoride Exposure on child neurobehavior (n = 229), published in the Journal of the American Medical Association, found that Los Angeles women who had higher maternal urinary fluoride levels during pregnancy rated their children higher on the child behavior checklist (CBCL) of neurobehavioral problems and internalizing symptoms including higher scores of emotionally reactive, somatic complaints, DSM-5–oriented Anxiety Problems scale, and even autism spectrum disorder. A 1 interquartile range increase in maternal urinary fluoride was associated with a 13.5% increase in scores for emotional reactivity, a 19.6% increase in scores for somatic complaints, an 11.3% increase in DSM-5–oriented Anxiety Problems and an 18.5% increase in DSM-5 Autism spectrum disorder with the magnitudes of the associations being larger across all trimesters than the third trimester alone. A 1 interquartile range increase equivalent to an increase of 0.7 mg/L also doubled the odds of having clinical or borderline clinical range scores on the child behavior checklist.

While this is the first U.S. cohort study to measure the effects of prenatal fluoride exposure on child neurobehavioral development it is not the first of its kind. An ecological cohort study conducted with Canadian pregnant women and child pairs in Calgary (n = 616), which briefly adjusted the naturally occurring fluoride in their drinking water from 0.1-0.4 mg/L to 0.7 mg/L until 2011, found no association between IQ at 3-5 years of age and exposure to the extra-fluoridated water during gestation during the larger Alberta Pregnancy Outcomes and Nutrition study but did find that maternal exposure to fluoride at the 0.7 mg/L level during pregnancy resulted in lower inhibitory control and cognitive flexibility among children 3-5 years of age. Another birth cohort study in Mexico (n = 210) that used data gathered by existing longitudinal birth cohort studies, found that higher maternal urinary fluoride levels, with an interquartile range of 0.5 mg/L, was associated with higher odds of children developing ADHD symptoms including a 2.84 higher score on the DSM-IV inattention index and a 2.47 higher score on the ADHD index with a 1 interquartile range increase in maternal urinary fluoride concentrations. Another Mexican birth cohort study that pulled data from participants in the larger ELEMENT study that had maternal urinary fluoride measurements from each trimester found that 0.5 mg/L increase in the latter predicted a 2.12 decrease on the longitudinal General Cognitive Index and a 2.63 point decrease on Performance IQ scores between the ages of 3 to 5 years and 6 to 12 years.

As I pointed out last year in (Part 1) 18 high quality studies in the National Toxicology Program systematic review provide evidence of an association between higher fluoride exposure, lower IQ and other neurodevelopmental and cognitive impairments in children.This latest study of prenatal exposure and the similar ones add to the mounting evidence that the fluoride salts added to tap water can be a neurotoxin not only at the maximum “safe” dosage of 1.5 mg/L but also at the administrative dosages of 0.7 mg/L.