ArticleEnvironmental research2021
Critical windows of fluoride neurotoxicity in Canadian children.
Article in Environmental research, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. An erratum has been issued. Cited by 35 papers, 2 of them syntheses that pooled it.
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The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
35 citing papers in PubMed, 2 syntheses or guidelines pooled it, 60 citations in OpenAlex.
- Fluoride Exposure and ADHD: A Systematic Review of Epidemiological Studies.Medicina (Kaunas, Lithuania) · 2023Pooled it
- Biomimetic hydroxyapatite and caries prevention: a systematic review and meta-analysis.Canadian journal of dental hygiene : CJDH = Journal canadien de l'hygiene dentaire : JCHD · 2021Pooled it
- Caries-preventing effect of a hydroxyapatite-toothpaste in adults: a 18-month double-blinded randomized clinical trial.Frontiers in public health · 2023Trial
- Relationships between Toenail, Urinary, and Drinking-water Fluoride Concentrations in a Pregnancy Cohort using Private Water Systems in the United States.Biological trace element research · 2026Article
- Grape Seed Proanthocyanins Extract Ameliorates the Neurotoxicity Induced by Fluoride Through mTOR/p70s6k Signaling Pathway in Vivo and in Vitro.Cell biochemistry and biophysics · 2026Article
- Comparison of the Caries Remineralizing Effects of Dentifrices Based on Natural Hydroxyapatite, Synthetic Hydroxyapatite, and Fluoride: A pH Cycling Study.Biomimetics (Basel, Switzerland) · 2026Article
- Fluoride and the brain: A systematic review of neurotoxicity and developmental risks.Genetics and molecular biology · 2026Article
- International fluoride symposium: effects of fluoride on human health and its mechanisms of action - a meeting report.BMC proceedings · 2025Article
- The sugar industry's efforts to manipulate research on fluoride effectiveness and toxicity: a ninety-year history.Environmental health : a global access science source · 2025Article
- Updated consumer risk assessment of fluoride in food and drinking water including the contribution from other sources of oral exposure.EFSA journal. European Food Safety Authority · 2025Article
- Article
- Evaluation of the Efficacy of a Dentifrice Tablet to Prevent Dental Caries: A Microbial Study.Dentistry journal · 2025Article
- Prenatal and Childhood Exposure to Fluoride and Cognitive Development: Findings from the Longitudinal MINIMat Cohort in Rural Bangladesh.Environmental health perspectives · 2025Article
- Correlation of fluoride intake with haemoglobin level and intelligence quotient in 8-12 year aged children: an observational study from India.BMC public health · 2025Observational
- Soft Drinks as a Dietary Source of Fluoride Exposure.Biological trace element research · 2024Article
- Fluoride and children's IQ: evidence of causation lacking.Evidence-based dentistry · 2024Article
- Water Fluoridation and Birth Outcomes in California.Environmental health perspectives · 2024Article
- Maternal Urinary Fluoride and Child Neurobehavior at Age 36 Months.JAMA network open · 2024Article
- Dose dependence of prenatal fluoride exposure associations with cognitive performance at school age in three prospective studies.European journal of public health · 2024Article
- Regional and racial/ethnic inequalities in public drinking water fluoride concentrations across the US.Journal of exposure science & environmental epidemiology · 2024Article
Corrections and comments
- Erratum issued
Authors and funding
9 authors at 5 institutions in 2 countries.
Funding
Abstract
backgroundFluoride has been associated with IQ deficits during early brain development, but the period in which children are most sensitive is unknown.
objectiveWe assessed effects of fluoride on IQ scores across prenatal and postnatal exposure windows.
methodsWe used repeated exposures from 596 mother-child pairs in the Maternal-Infant Research on Environmental Chemicals pregnancy and birth cohort. Fluoride was measured in urine (mg/L) collected from women during pregnancy and in their children between 1.9 and 4.4 years; urinary fluoride was adjusted for specific gravity. We estimated infant fluoride exposure (mg/day) using water fluoride concentration and duration of formula-feeding over the first year of life. Intelligence was assessed at 3-4 years using the Wechsler Preschool and Primary Scale of Intelligence-III. We used generalized estimating equations to examine the associations between fluoride exposures and IQ, adjusting for covariates. We report results based on standardized exposures given their varying units of measurement.
resultsThe association between fluoride and performance IQ (PIQ) significantly differed across prenatal, infancy, and childhood exposure windows collapsing across child sex (p = .001). The strongest association between fluoride and PIQ was during the prenatal window, B = -2.36, 95% CI: -3.63, -1.08; the association was also significant during infancy, B = -2.11, 95% CI: -3.45, -0.76, but weaker in childhood, B = -1.51, 95% CI: -2.90, -0.12. Within sex, the association between fluoride and PIQ significantly differed across the three exposure windows (boys: p = .01; girls: p = .01); among boys, the strongest association was during the prenatal window, B = -3.01, 95% CI: -4.60, -1.42, whereas among girls, the strongest association was during infancy, B = -2.71, 95% CI: -4.59, -0.83. Full-scale IQ estimates were weaker than PIQ estimates for every window. Fluoride was not significantly associated with Verbal IQ across any exposure window.
conclusionAssociations between fluoride exposure and PIQ differed based on timing of exposure. The prenatal window may be critical for boys, whereas infancy may be a critical window for girls.
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Registered trials
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