Associations of prenatal glyphosate exposure with child neurodevelopment in a Canadian pregnancy cohort study

Meaghan Hall; Jillian Ashley-Martin; Christine Till; Janice Hu; Bruce Lanphear; Cynthia Curl; Tye E Arbuckle; Michel Boivin; Linda Booij; Gina Muckle; Mandy Fisher; Elizabeth Asztalos; Maryse F Bouchard; Amanda J MacFarlane; Carly Hyland

doi:10.1016/j.envint.2025.109480

Associations of prenatal glyphosate exposure with child neurodevelopment in a Canadian pregnancy cohort study

Environ Int. 2025 May:199:109480. doi: 10.1016/j.envint.2025.109480. Epub 2025 Apr 17.

Authors

Affiliations

¹ Faculty of Health, York University, Toronto, ON, Canada.
² Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada. Electronic address: jillian.ashley-martin@hc-sc.gc.ca.
³ Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada.
⁴ Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, Canada.
⁵ School of Public and Population Health, Boise State University, Boise, ID, United States.
⁶ École de Psychologie, Université Laval, Québec, QC, Canada.
⁷ Department of Psychiatry, McGill University, Montreal, QC, Canada; CHU Sainte-Justine Hospital Research Centre, Montreal, QC, Canada.
⁸ École de Psychologie, Université Laval, Québec, QC, Canada; Centre de Recherche du CHU de Québec-Université Laval, Laval, QC, Canada.
⁹ Department of Newborn & Developmental Paediatrics, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada.
¹⁰ Institut National de la RechercheScientifique, Laval, QC, Canada.
¹¹ Texas A&M Agriculture, Food, and Nutrition Evidence Center, Fort Worth, TX, United States; Department of Nutrition, Texas A&M University, College Station, TX, United States.
¹² Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, CA, United States; UC Agriculture and Natural Resources, Berkeley, CA, United States.

PMID: 40344873
DOI: 10.1016/j.envint.2025.109480

Abstract

Objective: Glyphosate is the most widely used pesticide worldwide. Few epidemiologic studies have examined the potential for neurotoxicity by glyphosate or its degradate, Aminomethylphosphonic Acid (AMPA). We examined associations of maternal urinary glyphosate and AMPA concentrations with child cognitive, social, and behavioural functioning in participants enrolled in the Maternal-Infant Research on Environmental Chemicals (MIREC) study.

Methods: Maternal urinary glyphosate and AMPA concentrations were measured in first trimester spot urine samples. We assessed children's cognition (IQ) at 3-4 years of age (n = 572) using the Wechsler Preschool and Primary Scale of Intelligence-III. Social (n = 566) and behavioural (n = 840) functioning were assessed using parent-report versions of the Social Responsiveness Scale-2 and Behavioral Assessment System for Children-2. We quantified associations between maternal urinary glyphosate and AMPA concentrations and child neurodevelopmental outcomes using multivariable linear regression models and assessed effect modification by child sex, maternal folic acid, and plasma folate.

Results: Median (IQR) urinary glyphosate and AMPA concentrations were 0.31 (0.33) μg/L and 0.25 (0.25) μg/L. Maternal urinary glyphosate and AMPA concentrations were not significantly associated with children's cognitive, social or behavioural functioning, and there was no evidence of effect modification. We found a non-significant inverse trend between maternal urinary AMPA concentrations and Performance IQ (B = -0.85; 95 %CI: -1.71,0.01).

Conclusion: In this primarily urban cohort of Canadian mother-child pairs, prenatal glyphosate and AMPA exposure were not significantly associated with child neurodevelopment. Further evaluation of glyphosate as a potential developmental neurotoxicant in a study with multiple urine samples per participant and at higher exposure levels is warranted.

Keywords: AMPA; Glyphosate; Neurodevelopment; Pregnancy.

MeSH terms

Adult
Canada
Child Development* / drug effects
Child, Preschool
Cognition / drug effects
Cohort Studies
Female
Glycine* / analogs & derivatives
Glycine* / toxicity
Glycine* / urine
Glyphosate
Herbicides* / toxicity
Herbicides* / urine
Humans
Intelligence / drug effects
Male
Maternal Exposure* / statistics & numerical data
Organophosphonates
Pregnancy
Prenatal Exposure Delayed Effects* / chemically induced
Prenatal Exposure Delayed Effects* / epidemiology

Substances

Glyphosate
Glycine
Herbicides
aminomethylphosphonic acid (AMPA)
Organophosphonates