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Flawed MIREC fluoride and intelligence quotient publications: A failed attempt to undermine community water
Juliet R Guichon1, Colin Cooper2, Andrew Rugg-Gunn3
1Department of Community Health Sciences and Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
Objective:
To assess the evidence presented in a set of articles that use the Canadian Maternal-Infant Research on Environmental Chemicals (MIREC) study database to claim that community water fluoridation (CWF) is associated with harm to foetal and infant cognitive development.
Methods:
Critical appraisal of measurements and processes in the MIREC database, and articles derived therefrom. MIREC's cohort is approximately 2000 pregnant women recruited in 10 centres across Canada, 2008-2011, leading to measuring 512 children aged 3-6 years in six cities. Fluoride exposure was measured by city fluoridation status, self-reports and maternal spot urine samples. Intelligence Quotient (IQ) was measured using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III) by different assessors in each city.
Results:
MIREC's fluoride and IQ measurements are invalid and therefore cannot support the claim that CWF is associated with IQ decline in children.
Conclusions:
The MIREC fluoride-IQ articles' results should be considered unacceptable for legal and policy purposes; other water fluoridation studies and systematic reviews show no effect of fluoridation on cognition.
