Association of Glyphosate Exposure with Blood DNA Methylation in a Cross-Sectional Study of Postmenopausal Women

Abstract

Background: Glyphosate is the most commonly used herbicide in the world and is purported to have a variety of health effects, including endocrine disruption and an elevated risk of several types of cancer. Blood DNA methylation has been shown to be associated with many other environmental exposures, but to our knowledge, no studies to date have examined the association between blood DNA methylation and glyphosate exposure. Objective: We conducted an epigenome-wide association study to identify DNA methylation loci associated with urinary glyphosate and its metabolite aminomethylphosphonic acid (AMPA) levels. Secondary goals were to determine the association of epigenetic age acceleration with glyphosate and AMPA and develop blood DNA methylation indices to predict urinary glyphosate and AMPA levels. Methods: For 392 postmenopausal women, white blood cell DNA methylation was measured using the Illumina Infinium MethylationEPIC BeadChip array. Glyphosate and AMPA were measured in two urine samples per participant using liquid chromatography–tandem mass spectrometry. Methylation differences at the probe and regional level associated with glyphosate and AMPA levels were assessed using a resampling-based approach. Probes and regions that had an false discovery rate in of 1,000 subsamples of the study population were considered differentially methylated. Differentially methylated sites from the probe-specific analysis were combined into a methylation index. Epigenetic age acceleration from three epigenetic clocks and an epigenetic measure of pace of aging were examined for associations with glyphosate and AMPA. Results: We identified 24 CpG sites whose methylation level was associated with urinary glyphosate concentration and two associated with AMPA. Four regions, within the promoters of the MSH4 , KCNA6 , ABAT , and NDUFAF2 / ERCC8 genes, were associated with glyphosate levels, along with an association between ESR1 promoter hypomethylation and AMPA. The methylation index accurately predicted glyphosate levels in an internal validation cohort. AMPA, but not glyphosate, was associated with greater epigenetic age acceleration. Discussion: Glyphosate and AMPA exposure were associated with DNA methylation differences that could promote the development of cancer and other diseases. Further studies are warranted to replicate our results, determine the functional impact of glyphosate- and AMPA-associated differential DNA methylation, and further explore whether DNA methylation could serve as a biomarker of glyphosate exposure. https://doi.org/10.1289/EHP10174

Glyphosate infiltrates the brain and increases pro-inflammatory cytokine TNFα: implications for neurodegenerative disorders

“…Urine samples were prepared as previously described [ 30 , 31 , 33 ], with minor modifications. Briefly, mouse urine was diluted 10,000 -fold with water containing 0.1% formic acid.…”

Is exposure to pesticides associated with biological aging? A systematic review and meta-analysis

“…Among these, 24 articles were excluded (reasons for exclusion were in Fig. 1), yielding a total of 20 eligible articles for the systematic review (Ali et al, 2023; Andreotti et al, 2015; Cosemans et al, 2022; de Oliveira et al, 2019; de Prado-Bert et al, 2021; dos Santos et al, 2022; Duan et al, 2017; Guzzardi et al, 2016; Hoang et al, 2021; Hou et al, 2013; Kahl, da Silva, et al, 2018; Kahl, Dhillon, Fenech, et al, 2018; Kahl, Dhillon, Simon, et al, 2018; Kahl et al, 2016; Karimi et al, 2020; Lind et al, 2018; Lucia et al, 2022; Ock et al, 2020; Saad-Hussein et al, 2019; Shin et al, 2010). Two additional articles were identified through reference lists of selected systematic reviews (Passos et al, 2022) (Fig.…”

“…One study included a wide range of pesticides including chlorophenoxy (Dicamba, 2,4-D), chloroacetanilides (Acetochlor, Metolachlor), Pyridine (Picloram) and Trazines (Atrazine) (Hoang et al, 2021). Most studies focused on more than one epigenetic clock, including Horvath (Hoang et al, 2021; Lucia et al, 2022), Hannum (Hoang et al, 2021; Lind et al, 2018; Lucia et al, 2022), PhenoAge (Hoang et al, 2021; Lucia et al, 2022), DunedinPoAm (Lucia et al, 2022), GrimAge (Hoang et al, 2021), and Horvath Skin and Blood (de Prado-Bert et al, 2021; Hoang et al, 2021). Among these, the Hannum clock was the most frequently utilized, being employed in three studies.…”

“…Three studies reported positive significant associations between metabolites of four pesticides (p,p’-DDE, DDT, TNC, and AMPA) and accelerated epigenetic aging (Hoang et al, 2021; Lind et al, 2018; Lucia et al, 2022). On the contrary, one study reported a negative association between dimethyldithiophosphate (DMDTP) and epigenetic age; they interpreted this as the result of higher intake of fruits and vegetables; however the results did not change substantially once additionally adjusted for fruit intake, vegetable intake or urinary hippurate, a metabolite marker of fruits and vegetables (de Prado-Bert et al, 2021).…”

Effects of Aminomethylphosphonic Acid on the Transcriptome and Metabolome of Red Swamp Crayfish, Procambarus clarkii

“…The rest of the P. clarkii samples were used as a control group. The AMPA was purchased from Sigma-Aldrich as a 40% water solution of N-phosphonomethyl glycine-monoisopropylamine salt, was diluted in phosphate-buffered saline (PBS) 1X, and adjusted to pH 7.4 with NaOH [27,28]. AMPA with a purity above 98% (analytical standard) was obtained from Sigma-Aldrich Chemical Company (Spain, Madrid).…”