title: Ambient air pollution and birth weight in full-term infants in Atlanta, 1994-2004.
abstract: BACKGROUND
  An emerging body of evidence suggests that ambient levels of air pollution during pregnancy are associated with fetal growth.
  
  
  OBJECTIVE
  We examined relationships between birth weight and temporal variation in ambient levels of carbon monoxide, nitrogen dioxide (NO₂), sulfur dioxide (SO₂), ozone, particulate matter ≤ 10 μm in diameter (PM₁₀), ≤ 2.5 μm (PM(2.5)), 2.5 to 10 µm (PM(2.5-10)), and PM(2.5) chemical component measurements for 406,627 full-term births occurring between 1994 and 2004 in five central counties of metropolitan Atlanta.
  
  
  METHODS
  We assessed relationships between birth weight and pollutant concentrations during each infant's first month of gestation and third trimester, as well as in each month of pregnancy using distributed lag models. We also conducted capture-area analyses limited to mothers residing within 4 miles (6.4 km) of each air quality monitoring station.
  
  
  RESULTS
  In the five-county analysis, ambient levels of NO₂, SO₂, PM(2.5) elemental carbon, and PM(2.5) water-soluble metals during the third trimester were significantly associated with small reductions in birth weight (-4 to -16 g per interquartile range increase in pollutant concentrations). Third-trimester estimates were generally higher in Hispanic and non-Hispanic black infants relative to non-Hispanic white infants. Distributed lag models were also suggestive of associations between air pollutant concentrations in late pregnancy and reduced birth weight. The capture-area analyses provided little support for the associations observed in the five-county analysis.
  
  
  CONCLUSIONS
  Results provide some support for an effect of ambient air pollution in late pregnancy on birth weight in full-term infants.
authors.affiliation: Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia 30322, USA. ldarrow@sph.emory.edu
authors.forename: Lyndsey A
authors.initials: LA
authors.lastname: Darrow
authors.forename: Mitchel
authors.initials: M
authors.lastname: Klein
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Strickland
authors.forename: James A
authors.initials: JA
authors.lastname: Mulholland
authors.forename: Paige E
authors.initials: PE
authors.lastname: Tolbert
mesh_terms: D000328:Adult; D000397:Air Pollution / Q000009:adverse effects*; D001724:Birth Weight / Q000187:drug effects*; D002248:Carbon Monoxide / Q000633:toxicity; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010126:Ozone / Q000633:toxicity; D052638:Particulate Matter / Q000633:toxicity*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D013458:Sulfur Dioxide / Q000633:toxicity; D055815:Young Adult
chemical_list: D052638:Particulate Matter; D013458:Sulfur Dioxide; D010126:Ozone; D002248:Carbon Monoxide