Association of Lifetime Exposure to Glyphosate and Aminomethylphosphonic Acid (AMPA) with Liver Inflammation and Metabolic Syndrome at Young Adulthood: Findings from the CHAMACOS Study

BACKGROUND: The prevalence of liver disorders and metabolic syndrome has increased among youth. Glyphosate, the most widely used herbicide worldwide, could contribute to the development of these conditions.OBJECTIVE: We aimed to assess whether lifetime exposure to glyphosate and its degradation product, aminomethylphosphonic acid (AMPA), is asso-ciated with elevated liver transaminases and metabolic syndrome among young adults.METHODS: We conducted a prospective cohort study (n = 480 mother-child dyads) and a nested case-control study (n = 60 cases with elevated liver transaminases and 91 controls) using data from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS). We meas-ured glyphosate and AMPA concentrations in urine samples collected during pregnancy and at child ages 5, 14, and 18 y from cases and controls. We calculated glyphosate residue concentrations: [glyphosate + o1.5 x AMPA thorn ]. We estimated the amount of agricultural-use glyphosate applied within a 1-km radius of every residence from pregnancy to age 5 y for the full cohort using California Pesticide Use Reporting data. We assessed liver transa-minases and metabolic syndrome at 18 y of age.RESULTS: Urinary AMPA at age 5 y was associated with elevated transaminases [relative risk (RR) per 2-fold increase =1.27, 95% confidence interval (CI): 1.06, 1.53] and metabolic syndrome (RR = 2.07, 95% CI: 1.38, 3.11). Urinary AMPA and glyphosate residues at age 14 y were associated with metabolic syndrome [RR = 1.80 (95% CI: 1.10, 2.93) and RR = 1.88 (95% CI: 1.03, 3.42), respectively]. Overall, a 2-fold increase in urinary AMPA during childhood was associated with a 14% and a 55% increased risk of elevated liver transaminases and metabolic syndrome, respectively. Living near agricultural glyphosate applications during early childhood (birth to 5 y of age) was also associated with metabolic syndrome at age 18 y in the case-control group (RR = 1.53, 95% CI: 1.16, 2.02).DISCUSSION: Childhood exposure to glyphosate and AMPA may increase risk of liver and cardiometabolic disorders in early adulthood, which could lead to more serious diseases later in life. https://doi.org/10.1289/EHP11721

Automated summary

This study examines the impact of glyphosate, the most widely used herbicide, on young adults and finds that it is associated with metabolic syndrome and elevated liver transaminases. The concentration of AMPA in urine is related to these conditions. Childhood exposure to glyphosate and AMPA may increase the risk of liver and cardiometabolic disorders in early adulthood, leading to more serious diseases later in life.