Relationship between Environmental Phthalate Exposure and the Intelligence of School-Age Children

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Background

Concern over phthalates has emerged because of their potential toxicity to humans.

Objective

We investigated the relationship between the urinary concentrations of phthalate metabolites and children’s intellectual functioning.

Methods

This study enrolled 667 children at nine elementary schools in five South Korean cities. A cross-sectional examination of urine phthalate concentrations was performed, and scores on neuropsychological tests were obtained from both the children and their mothers.

Results

We measured mono-2-ethylhexyl phthalate (MEHP) and mono(2-ethyl-5-oxohexyl)phthalate (MEOHP), both metabolites of di(2-ethylhexyl)phthalate (DEHP), and mono- n-butyl phthalate (MBP), a metabolite of dibutyl phthalate (DBP), in urine samples. The geometric mean (ln) concentrations of MEHP, MEOHP, and MBP were 21.3 μg/L [geometric SD (GSD) = 2.2 μg/L; range, 0.5–445.4], 18.0 μg/L (GSD = 2.4; range, 0.07–291.1), and 48.9 μg/L (GSD = 2.2; range, 2.1–1645.5), respectively. After adjusting for demographic and developmental covariates, the Full Scale IQ and Verbal IQ scores were negatively associated with DEHP metabolites but not with DBP metabolites. We also found a significant negative relationship between the urine concentrations of the metabolites of DEHP and DBP and children’s vocabulary subscores. After controlling for maternal IQ, a significant inverse relationship between DEHP metabolites and vocabulary subscale score remained. Among boys, we found a negative association between increasing MEHP phthalate concentrations and the sum of DEHP metabolite concentrations and Wechsler Intelligence Scale for Children vocabulary score; however, among girls, we found no significant association between these variables.

Conclusion

Controlling for maternal IQ and other covariates, the results show an inverse relationship between phthalate metabolites and IQ scores; however, given the limitations in cross-sectional epidemiology, prospective studies are needed to fully explore these associations.

Related collections

Most cited references 46

Record: found
Abstract: found
Article: not found

Prenatal Phenol and Phthalate Exposures and Birth Outcomes

Mary S Wolff, Stephanie M. Engel, Gertrud S. Berkowitz … (2008)

Background Many phthalates and phenols are hormonally active and are suspected to alter the course of development. Objective We investigated prenatal exposures to phthalate and phenol metabolites and their associations with body size measures of the infants at birth. Methods We measured 5 phenol and 10 phthalate urinary metabolites in a multiethnic cohort of 404 women in New York City during their third trimester of pregnancy and recorded size of infants at birth. Results Median urinary concentrations were > 10 μg/L for 2 of 5 phenols and 6 of 10 phthalate monoester metabolites. Concentrations of low-molecular-weight phthalate monoesters (low-MWP) were approximately 5-fold greater than those of high-molecular-weight metabolites. Low-MWP metabolites had a positive association with gestational age [0.97 day gestational age per ln-biomarker; 95% confidence interval (CI), 0.07–1.9 days, multivariate adjusted] and with head circumference. Higher prenatal exposures to 2,5-dichlorophenol (2,5-DCP) predicted lower birth weight in boys (−210 g average birth weight difference between the third tertile and first tertile of 2,5-DCP; 95% CI, 71–348 g). Higher maternal benzophenone-3 (BP3) concentrations were associated with a similar decrease in birth weight among girls but with greater birth weight in boys. Conclusions We observed a range of phthalate and phenol exposures during pregnancy in our population, but few were associated with birth size. The association of 2,5-DCP and BP3 with reduced or increased birth weight could be important in very early or small-size births. In addition, positive associations of urinary metabolites with some outcomes may be attributable partly to unresolved confounding with maternal anthropometric factors.

0 comments Cited 157 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

The Association between Asthma and Allergic Symptoms in Children and Phthalates in House Dust: A Nested Case–Control Study

Carl-Gustaf Bornehag, Jan Sundell, Charles Weschler … (2004)

Global phthalate ester production has increased from very low levels at the end of World War II to approximately 3.5 million metric tons/year. The aim of the present study was to investigate potential associations between persistent allergic symptoms in children, which have increased markedly in developed countries over the past three decades, and the concentration of phthalates in dust collected from their homes. This investigation is a case–control study nested within a cohort of 10,852 children. From the cohort, we selected 198 cases with persistent allergic symptoms and 202 controls without allergic symptoms. A clinical and a technical team investigated each child and her or his environment. We found higher median concentrations of butyl benzyl phthalate (BBzP) in dust among cases than among controls (0.15 vs. 0.12 mg/g dust). Analyzing the case group by symptoms showed that BBzP was associated with rhinitis (p = 0.001) and eczema (p = 0.001), whereas di(2-ethylhexyl) phthalate (DEHP) was associated with asthma (p = 0.022). Furthermore, dose–response relationships for these associations are supported by trend analyses. This study shows that phthalates, within the range of what is normally found in indoor environments, are associated with allergic symptoms in children. We believe that the different associations of symptoms for the three major phthalates—BBzP, DEHP, and di-n-butyl phthalate—can be explained by a combination of chemical physical properties and toxicologic potential. Given the phthalate exposures of children worldwide, the results from this study of Swedish children have global implications.

0 comments Cited 154 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Temporal Variability of Urinary Phthalate Metabolite Levels in Men of Reproductive Age

Russ Hauser, John D. Meeker, Sohee Park … (2004)

Phthalates are a family of multifunctional chemicals widely used in personal care and other consumer products. The ubiquitous use of phthalates results in human exposure through multiple sources and routes, including dietary ingestion, dermal absorption, inhalation, and parenteral exposure from medical devices containing phthalates. We explored the temporal variability over 3 months in urinary phthalate metabolite levels among 11 men who collected up to nine urine samples each during this time period. Eight phthalate metabolites were measured by solid-phase extraction–high-performance liquid chromatography–tandem mass spectrometry. Statistical analyses were performed to determine the between- and within-subject variance apportionment, and the sensitivity and specificity of a single urine sample to classify a subject’s 3-month average exposure. Five of the eight phthalates were frequently detected. Monoethyl phthalate (MEP) was detected in 100% of samples; monobutyl phthalate, monobenzyl phthalate, mono-2-ethylhexyl phthalate (MEHP), and monomethyl phthalate were detected in > 90% of samples. Although we found both substantial day-to-day and month-to-month variability in each individual’s urinary phthalate metabolite levels, a single urine sample was moderately predictive of each subject’s exposure over 3 months. The sensitivities ranged from 0.56 to 0.74. Both the degree of between- and within-subject variance and the predictive ability of a single urine sample differed among phthalate metabolites. In particular, a single urine sample was most predictive for MEP and least predictive for MEHP. These results suggest that the most efficient exposure assessment strategy for a particular study may depend on the phthalates of interest.

0 comments Cited 132 times – based on 0 reviews      Review now

Bookmark

All references

Author and article information

Journal

Journal ID (nlm-ta): Environ Health Perspect

Title: Environmental Health Perspectives

Publisher: National Institute of Environmental Health Sciences

ISSN (Print): 0091-6765

ISSN (Electronic): 1552-9924

Publication date (Print): July 2010

Publication date (Electronic): 1 March 2010

Volume: 118

Issue: 7

Pages: 1027-1032

Affiliations

[1 ] Division of Child and Adolescent Psychiatry, Department of Psychiatry and Institute of Human Behavioral Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea

[2 ] Department of Psychiatry, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea

[3 ] Department of Preventive Medicine, Seoul National University College of Medicine and Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea

[4 ] Department of Psychiatry, Seoul National University Bundang Hospital, Seongnam, Republic of Korea

[5 ] Department of Psychiatry, Gil Medical Center, Gachon University of Medicine and Science, Incheon, Republic of Korea

[6 ] Department of Neuropsychiatry, Dongguk University International Hospital, Dongguk University College of Medicine, Goyang, Republic of Korea

Author notes

Address correspondence to S. Bhang, Department of Psychiatry, Ulsan University Hospital, University of Ulsan College of Medicine, 290-3 Jeonha-Dong, Dong-Gu, Ulsan, 682-714, South Korea. Telephone: 82-52-250- 7070. Fax: 82-52-232-3309. E-mail: dresme@ 123456dreamwiz.com

Article

Publisher ID: ehp-118-1027

DOI: 10.1289/ehp.0901376

PMC ID: 2920903

PubMed ID: 20194078

SO-VID: 156485a9-02f8-4642-95ca-7b5098b411a0

Copyright © This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.

Relationship between Environmental Phthalate Exposure and the Intelligence of School-Age Children

Read this article at

Abstract

Background

Objective

Methods

Results

Conclusion

Related collections

Chinese Journal of School Health

Most cited references 46

Prenatal Phenol and Phthalate Exposures and Birth Outcomes

The Association between Asthma and Allergic Symptoms in Children and Phthalates in House Dust: A Nested Case–Control Study

Temporal Variability of Urinary Phthalate Metabolite Levels in Men of Reproductive Age

Author and article information

Journal

Affiliations

Author notes

Article

History

Categories

Comments

Comment on this article

Similar content 203

Cited by 48

Most referenced authors 293