Concurrent Assessment of Phthalates/HEXAMOLL® DINCH Exposure and Wechsler Intelligence Scale for Children Performance in Three European Cohorts of the HBM4EU Aligned Studies

Abstract

Information about the effects of phthalates and non-phthalate substitute cyclohexane-1,2-dicarboxylic acid diisononyl ester (HEXAMOLL® DINCH) on children's neurodevelopment is limited. The aim of the present research is to evaluate the association between phthalate/HEXAMOLL® DINCH exposure and child neurodevelopment in three European cohorts involved in HBM4EU Aligned Studies. Participating subjects were school-aged children belonging to the Northern Adriatic cohort II (NAC-II), Italy, Odense Child Cohort (OCC), Denmark, and PCB cohort, Slovakia. In each cohort, children's neurodevelopment was assessed through the Full-Scale Intelligence Quotient score (FSIQ) of the Wechsler Intelligence Scale of Children test using three different editions. The children's urine samples, collected for one point in time concurrently with the neurodevelopmental evaluation, were analyzed for several phthalates/HEXAMOLL® DINCH biomarkers. The relation between phthalates/HEXAMOLL® DINCH and FSIQ was explored by applying separate multiple linear regressions in each cohort. The means and standard deviations of FSIQ were 109 ± 11 (NAC-II), 98 ± 12 (OCC), and 81 ± 15 (PCB cohort). In NAC-II, direct associations between FSIQ and DEHP's biomarkers were found: 5OH-MEHP+5oxo-MEHP (β = 2.56; 95% CI 0.58-4.55; N = 270), 5OH-MEHP+5cx-MEPP (β = 2.48; 95% CI 0.47-4.49; N = 270) and 5OH-MEHP (β = 2.58; 95% CI 0.65-4.51; N = 270). On the contrary, in the OCC the relation between DEHP's biomarkers and FSIQ tended to be inverse but imprecise (p-value ≥ 0.10). No associations were found in the PCB cohort. FSIQ was not associated with HEXAMOLL® DINCH in any cohort. In conclusion, these results do not provide evidence of an association between concurrent phthalate/DINCHHEXAMOLLR DINCH exposure and IQ in children.This work received external funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 733032 [“European Human Biomonitoring Initiative” (HBM4EU)] and received co-funding from the author’s organizations. NAC-II: This research was funded by: the European Union through its Sixth Framework Program for RTD (contract “PHIME” No. FOOD-CT-2006-016253); the Institute for Maternal and Child Health IRCCS “Burlo Garofolo”, Trieste, Italy (RC 12/12 funded by Ministry of Health—Italy); CROME LIFE Project “Cross-Mediterranean Environment and Health Network” (LIFE12 ENV/GR/001040). OCC: The cohort was funded by the Odense University Hospital, Denmark; the Region of Southern Denmark, The Municipality of Odense, Denmark; The University of Southern Denmark; the Mental Health Service of the Region of Southern Denmark; Odense Patient data Exploratory Network (OPEN), Den mark; The Danish Center for Hormone Disrupting Chemicals (MST-611-00012); The Danish Research Council (4004-00352B_FSS); Novo Nordisk Foundation, Denmark (grant no. NNF19OC0058266 and NNF17OC0029404); Sygeforsikring Danmark (journalnr. 2021-0173); The Collaborative foundation between Odense University Hospital and Rigshospitalet, Helsefonden, Beckettfonden, the Danish Mental Health Fund, Health Insurance Denmark. The LS-MS/MS equipment was financially supported by the Velux Foundation. PCB: PCB cohort was funded by the Slovak Research and Development Agency, project no. APVV-0571-12 and the Ministry of Health of the Slovak Republic, project no. 2014/47-SZU-11. The APC was funded by the European Union’s Horizon 2020 research and innovation program under grant agreement No. 733032.S