Effects of prenatal exposure to phthalates and Hexamoll® DINCH derived from urinary untargeted metabolomics analysis

BACKGROUND AND AIM: Phthalates and their substitute Hexamoll® DINCH® are a group of plasticisers with a production volume of millions of tons per year found in daily use products. There is a societal concern due to their endocrine-disrupting properties. Previous studies suggest that prenatal exposure to phthalates, ubiquitous, may adversely affect early childhood development. We aimed to investigate associations of prenatal plasticisers exposure with neurodevelopment and metabolic dysfunction in early childhood in the European Exposure and Health Examination Survey (EXHES) study (n=80 pairs of mother-neonate). METHODS: The links between in utero exposure to plasticisers, metabolic pathway dysregulation, and clinically observed phenotypes were drawn through a urinary untargeted metabolomics analysis using UPLCQ-TOF/MS, followed by integrative bioinformatics algorithms. Spectral pre-processing was performed using the Bioconductor R packages XCMS and CAMERA. The databases HMDB, Metlin, and Lipid Maps, were used for metabolites identification. Enrichment pathway analysis was performed using the MetaboAnalyst R package, which mapped significant biomarkers to known biochemical pathways based on the information in public databases (MetaCyc, Wikipathways, and KEGG). Also, we have developed, optimised and validated a new analytical method for the quantification of 14 phthalates metabolites (MEP, MBzP, MiBP, MnBP, MCHP, MnPeP, MEHP, 5OH-MEHP, 5oxo-MEHP, 5cx-MEHP, MnOP, OH-MiNP, cx-MiNP, and OH-MiDP) and 2 Hexamoll® DINCH® metabolites (OH-MINCH and cx-MINCH). Separation of the isomers was achieved following the developed online SPE LC-MS/MS method. The method mentioned above was applied in 80 pairs of mother-neonate. RESULTS:Most perturbed metabolic pathways were related to oxidative stress and stress-activated signalling pathways, including the tricarboxylic acid cycle (TCA cycle), the metabolism of amino acids, and phosphatidylcholines. CONCLUSIONS:This study is the first to measured 16 metabolites of plasticisers to assess prenatal exposure with children's neurodevelopment and metabolic dysfunction. These findings will provide information towards AOPs development relevant to neurotoxicity and metabolic abnormalities. KEYWORDS: microplastics, plasticisers, exposure