Maternal exposure to ambient air pollutants and risk of congenital anomalies

Environ Res. 2009 Feb;109(2):181-7. doi: 10.1016/j.envres.2008.11.007. Epub 2009 Jan 8.


Studies have suggested an association between maternal exposure to ambient air pollution and risk of congenital anomaly. The aim of this study is to investigate the association between exposure to black smoke (BS; particulate matter with aerodynamic diameter <4 microg/m(3)) and sulphur dioxide (SO(2)) during the first trimester of pregnancy and risk of congenital anomalies. We used a case-control study design among deliveries to mothers resident in the UK Northern health region during 1985-1990. Case data were ascertained from the population-based Northern Congenital Abnormality Survey and control data from national data on all births. Data on BS and SO(2) from ambient air monitoring stations were used to average the total pollutant exposure during the first trimester of pregnancy over the daily readings from all monitors within 10 km of the mother's residence. Logistic regression models estimated the association via odds ratios. A significant but weak positive association was found between nervous system anomalies and BS (OR=1.10 per increase of 1000 microg/m(3) total BS; 95% CI: 1.03, 1.18), but not with other anomaly subtypes. For SO(2), a significant negative association was found with congenital heart disease combined and patent ductus arteriosus: OR significantly <1 for all quartiles relative to the first quartile. The relationship between SO(2) levels and other anomaly subtypes was less clear cut: there were either no significant associations or a suggestion of a U-shaped relationship (OR significantly <1 for moderate compared to lowest levels, but not with high SO(2) levels). Overall, maternal exposure to BS and SO(2) in the Northern region had limited impact on congenital anomaly risk. Studies with detailed exposure assessment are needed to further investigate this relationship.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Air Pollutants / adverse effects*
  • Air Pollutants / analysis
  • Air Pollution / adverse effects
  • Air Pollution / analysis
  • Case-Control Studies
  • Confidence Intervals
  • Congenital Abnormalities / epidemiology*
  • Congenital Abnormalities / etiology
  • Ductus Arteriosus, Patent / epidemiology*
  • Ductus Arteriosus, Patent / etiology
  • Environmental Monitoring
  • Epidemiological Monitoring
  • Female
  • Heart Diseases / congenital
  • Heart Diseases / epidemiology
  • Heart Diseases / etiology
  • Humans
  • Infant, Newborn
  • Logistic Models
  • Male
  • Maternal Exposure / adverse effects*
  • Nervous System Malformations / epidemiology*
  • Nervous System Malformations / etiology
  • Odds Ratio
  • Particle Size
  • Pregnancy
  • Pregnancy Outcome
  • Pregnancy Trimester, First
  • Prenatal Exposure Delayed Effects
  • Risk Assessment
  • Risk Factors
  • Smoke / adverse effects*
  • Smoke / analysis
  • Sulfur Dioxide / adverse effects*
  • Sulfur Dioxide / analysis
  • United Kingdom / epidemiology


  • Air Pollutants
  • Smoke
  • Sulfur Dioxide