Maternal exposure to criteria air pollutants and congenital heart defects in offspring: results from the national birth defects prevention study.

Abstract

BACKGROUND:

Epidemiologic literature suggests that exposure to air pollutants is associated with fetal development.

OBJECTIVES:

We investigated maternal exposures to air pollutants during weeks 2-8 of pregnancy and their associations with congenital heart defects.

METHODS:

Mothers from the National Birth Defects Prevention Study, a nine-state case-control study, were assigned 1-week and 7-week averages of daily maximum concentrations of carbon monoxide, nitrogen dioxide, ozone, and sulfur dioxide and 24-hr measurements of fine and coarse particulate matter using the closest air monitor within 50 km to their residence during early pregnancy. Depending on the pollutant, a maximum of 4,632 live-birth controls and 3,328 live-birth, fetal-death, or electively terminated cases had exposure data. Hierarchical regression models, adjusted for maternal demographics and tobacco and alcohol use, were constructed. Principal component analysis was used to assess these relationships in a multipollutant context.

RESULTS:

Positive associations were observed between exposure to nitrogen dioxide and coarctation of the aorta and pulmonary valve stenosis. Exposure to fine particulate matter was positively associated with hypoplastic left heart syndrome but inversely associated with atrial septal defects. Examining individual exposure-weeks suggested associations between pollutants and defects that were not observed using the 7-week average. Associations between left ventricular outflow tract obstructions and nitrogen dioxide and between hypoplastic left heart syndrome and particulate matter were supported by findings from the multipollutant analyses, although estimates were attenuated at the highest exposure levels.

CONCLUSIONS:

Using daily maximum pollutant levels and exploring individual exposure-weeks revealed some positive associations between certain pollutants and defects and suggested potential windows of susceptibility during pregnancy.

• Authors: Jeanette A Stingone, Thomas J Luben, Julie L Daniels, Montserrat Fuentes, David B Richardson, Arthur S Aylsworth, Amy H Herring, Marlene Anderka, Lorenzo Botto, Adolfo Correa, Suzanne M Gilboa, Peter H Langlois, Bridget Mosley, Gary M Shaw, Csaba Siffel, Andrew F Olshan, National Birth Defects Prevention Study
• Journal: Environmental health perspectives (Environ Health Perspect) Vol. 122 Issue 8 Pg. 863-72 (Aug 2014) ISSN: 1552-9924 [Electronic] United States
• PMID: 24727555 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Air Pollutants
• Particulate Matter
• Sulfur Dioxide
• Ozone
• Nitrogen Dioxide

Topics

• Air Pollutants
• Female
• Heart Defects, Congenital (epidemiology, etiology)
• Humans
• Maternal Exposure (adverse effects)
• Nitrogen Dioxide (toxicity)
• Ozone (toxicity)
• Particulate Matter (toxicity)
• Pregnancy
• Sulfur Dioxide (toxicity)