Prenatal phthalate exposure and language development in toddlers from the Odense Child Cohort

Neurotoxicol Teratol. 2018 Jan-Feb:65:34-41. doi: 10.1016/j.ntt.2017.11.004. Epub 2017 Dec 1.

Abstract

Background: Phthalates are a group of chemicals found in a variety of consumer products. They have anti-androgenic properties and human studies have reported associations between prenatal phthalate exposure and neuropsychological development in the offspring despite different cognitive tests, different ages and varying timing of exposure.

Objectives: To investigate the association between prenatal phthalate exposure and language development in children aged 20-36months.

Methods: In the Odense Child Cohort, we analyzed 3rd trimester urine samples of 518 pregnant women for content of metabolites of diethyl, di-n-butyl, diisobutyl, butylbenzyl, di(2-ethylhexyl), and diisononyl phthalate, adjusted for osmolality. Language development was addressed using the Danish version of the MacArthur-Bates Communicative Development Inventories "Words and Sentences". Associations were assessed using logistic regression models comparing children below and above the 15th percentile while stratifying by sex and adjusting for maternal age and educational level.

Results: Phthalate metabolites were detectable in all samples although in lower levels than previous studies. Among boys, increased prenatal phthalate exposure was associated with lower scores in language development; odds ratios for vocabulary score below the 15th percentile with doubling in monoethyl phthalate, and summed di-(2-ethylhexyl) phthalate metabolites were respectively 1.24 (95% confidence interval: 1.05,1.46), and 1.33 (1.01,1.75). Similar associations were found for language complexity. No associations were found for girls.

Conclusions: Our findings are notable, as adverse associations were suggested even in this low-level exposed population, with only one spot urine sample for exposure assessment and control for confounders. Lower scores in early language development are of relevance to health as this test predicts later educational success.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Child, Preschool
  • Cohort Studies
  • Denmark
  • Environmental Pollutants / blood
  • Environmental Pollutants / toxicity*
  • Environmental Pollutants / urine
  • Female
  • Humans
  • Language Development*
  • Male
  • Maternal Exposure / adverse effects*
  • Phthalic Acids / blood
  • Phthalic Acids / toxicity*
  • Phthalic Acids / urine
  • Pregnancy
  • Prenatal Exposure Delayed Effects / blood
  • Prenatal Exposure Delayed Effects / chemically induced
  • Prenatal Exposure Delayed Effects / psychology*
  • Prenatal Exposure Delayed Effects / urine
  • Sex Factors

Substances

  • Environmental Pollutants
  • Phthalic Acids
  • phthalic acid