Combined effects of prenatal polycyclic aromatic hydrocarbons and material hardship on child IQ.
OBJECTIVE
Polycyclic aromatic hydrocarbons are common carcinogenic and neurotoxic urban air pollutants. Toxic exposures, including air pollution, are disproportionately high in communities of color and frequently co-occur with chronic economic deprivation.


OBJECTIVE
We examined whether the association between child IQ and prenatal exposure to polycyclic aromatic hydrocarbons differed between groups of children whose mothers reported high vs. low material hardship during their pregnancy and through child age 5. We tested statistical interactions between hardships and polycyclic aromatic hydrocarbons, as measured by DNA adducts in cord blood, to determine whether material hardship exacerbated the association between adducts and IQ scores.


METHODS
Prospective cohort. Participants were recruited from 1998 to 2006 and followed from gestation through age 7 years.


METHODS
Urban community (New York City)


METHODS
A community-based sample of 276 minority urban youth EXPOSURE MEASURE: Polycyclic aromatic hydrocarbon-DNA adducts in cord blood as an individual biomarker of prenatal polycyclic aromatic hydrocarbon exposure. Maternal material hardship self-reported prenatally and at multiple timepoints through early childhood.


METHODS
Child IQ at 7 years assessed using the Wechsler Intelligence Scale for Children.


RESULTS
Significant inverse effects of high cord PAH-DNA adducts on full scale IQ, perceptual reasoning and working memory scores were observed in the groups whose mothers reported a high level of material hardship during pregnancy or recurring high hardship into the child's early years, and not in those without reported high hardship. Significant interactions were observed between high cord adducts and prenatal hardship on working memory scores (β = -8.07, 95% CI (-14.48, -1.66)) and between high cord adducts and recurrent material hardship (β = -9.82, 95% CI (-16.22, -3.42)).


CONCLUSIONS
The findings add to other evidence that socioeconomic disadvantage can increase the adverse effects of toxic physical "stressors" like air pollutants. Observed associations between high cord adducts and reduced IQ were significant only among the group of children whose mothers reported high material hardship. These results indicate the need for a multifaceted approach to prevention.
Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA.
Julia
J
Vishnevetsky
Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA.
Deliang
D
Tang
Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Department of Biostatistics, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA.
Hsin-Wen
HW
Chang
Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA.
Emily L
EL
Roen
Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Department of Biostatistics, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA.
Ya
Y
Wang
Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; The Heilbrunn Center for Population and Family Health, Mailman School of Public Health, Columbia University, 60 Haven Avenue, New York, NY 10032, USA.
Virginia
V
Rauh
Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Department of Biostatistics, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA.
Shuang
S
Wang
Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Division of Pulmonary, Allergy and Critical Care of Medicine, Department of Medicine, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, USA; Division of Pediatric Allergy, Immunology and Rheumatology, Department of Pediatrics, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, USA.
Rachel L
RL
Miller
Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA.
Julie
J
Herbstman
Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA; Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA. Electronic address: fpp1@columbia.edu.
Frederica P
FP
Perera
D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007360:Intelligence / Q000187:drug effects*; D007361:Intelligence Tests; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D011084:Polycyclic Aromatic Hydrocarbons / Q000009:adverse effects* / Q000097:blood / Q000652:urine; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000523:psychology*; D011340:Problem Solving / Q000187:drug effects; D011446:Prospective Studies; D012959:Socioeconomic Factors; D014504:Urban Health; D014505:Urban Population
D011084:Polycyclic Aromatic Hydrocarbons
Adducts; Air pollution; Child IQ; PAH; Prenatal exposure