Prenatal organophosphate ester exposure and executive function in Norwegian preschoolers

Amber M Hall; Alexander P Keil; Giehae Choi; Amanda M Ramos; David B Richardson; Andrew F Olshan; Chantel L Martin; Gro D Villanger; Ted Reichborn-Kjennerud; Pål Zeiner; Kristin R Øvergaard; Amrit K Sakhi; Cathrine Thomsen; Heidi Aase; Stephanie M Engel

doi:10.1097/EE9.0000000000000251

Prenatal organophosphate ester exposure and executive function in Norwegian preschoolers

Environ Epidemiol. 2023 Jun 5;7(3):e251. doi: 10.1097/EE9.0000000000000251. eCollection 2023 Jun.

Authors

Amber M Hall¹, Alexander P Keil¹, Giehae Choi², Amanda M Ramos¹, David B Richardson¹, Andrew F Olshan¹, Chantel L Martin¹, Gro D Villanger³, Ted Reichborn-Kjennerud^{4

5}, Pål Zeiner^{4

6}, Kristin R Øvergaard^{4

6}, Amrit K Sakhi⁷, Cathrine Thomsen⁷, Heidi Aase³, Stephanie M Engel¹

Affiliations

¹ Department of Epidemiology, Gillings School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
² Department of Environmental Health and Engineering, Johns Hopkins University, Baltimore, Maryland.
³ Department of Child Health and Development, Division of Mental and Physical Health, Norwegian Institute of Public Health, Oslo, Norway.
⁴ Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
⁵ Department of Mental Disorders, Division of Mental and Physical Health, Norwegian Institute of Public Health, Oslo, Norway.
⁶ Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway.
⁷ Department of Food Safety, Division of Climate and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.

Abstract

Organophosphate esters (OPEs) are ubiquitous chemicals, used as flame retardants and plasticizers. OPE usage has increased over time as a substitute for other controlled compounds. This study investigates the impact of prenatal OPE exposure on executive function (EF) in preschoolers.

Methods: We selected 340 preschoolers from the Norwegian Mother, Father, and Child Cohort Study. Diphenyl-phosphate (DPhP), di-n-butyl-phosphate (DnBP), bis(2-butoxyethyl) phosphate (BBOEP), and bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) were measured in maternal urine. EF was measured using the Behavior Rating Inventory of Executive Functioning-Preschool (BRIEF-P) and the Stanford-Binet fifth edition (SB-5). EF scores were scaled so a higher score indicated worse performance. We estimated exposure-outcome associations and evaluated modification by child sex using linear regression.

Results: Higher DnBP was associated with lower EF scores across multiple rater-based domains. Higher DPhP and BDCIPP were associated with lower SB-5 verbal working memory (β = 0.49, 95% CI = 0.12, 0.87; β = 0.53, 95% CI = 0.08, 1.02), and higher BBOEP was associated with lower teacher-rated inhibition (β = 0.34, 95% CI = 0.01, 0.63). DPhP was associated with lower parent-reported BRIEF-P measures in boys but not girls [inhibition: boys: 0.37 (95% CI = 0.03, 0.93); girls: -0.48 (95% CI = -1.27, 0.19); emotional control: boys: 0.44 (95% CI = -0.13, 1.26); girls: -0.83 (95% CI = -1.73, -0.00); working memory: boys: 0.49 (95% CI = 0.03, 1.08); girls: -0.40 (95% CI = -1.11, 0.36)]. Fewer sex interactions were observed for DnBP, BBOEP, and BDCIPP, with irregular patterns observed across EF domains.

Conclusions: We found some evidence prenatal OPE exposure may impact EF in preschoolers and variation in associations by sex.

Keywords: BBOEP; BDCIPP; Behavior; Control; DPhP; DnBP; Emotional; Executive function; Flame retardants; Inhibition; MBRN; MoBa; Neurodevelopment; Norway; Organophosphate ester; Preschool; Working memory.

Abstract

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