title: Traffic-related air toxics and term low birth weight in Los Angeles County, California.
abstract: BACKGROUND
  Numerous studies have linked criteria air pollutants with adverse birth outcomes, but there is less information on the importance of specific emission sources, such as traffic, and air toxics.
  
  
  OBJECTIVE
  We used three exposure data sources to examine odds of term low birth weight (LBW) in Los Angeles, California, women when exposed to high levels of traffic-related air pollutants during pregnancy.
  
  
  METHODS
  We identified term births during 1 June 2004 to 30 March 2006 to women residing within 5 miles of a South Coast Air Quality Management District (SCAQMD) Multiple Air Toxics Exposure Study (MATES III) monitoring station. Pregnancy period average exposures were estimated for air toxics, including polycyclic aromatic hydrocarbons (PAHs), source-specific particulate matter < 2.5 μm in aerodynamic diameter (PM2.5) based on a chemical mass balance model, criteria air pollutants from government monitoring data, and land use regression (LUR) model estimates of nitric oxide (NO), nitrogen dioxide (NO2) and nitrogen oxides (NOx). Associations between these metrics and odds of term LBW (< 2,500 g) were examined using logistic regression.
  
  
  RESULTS
  Odds of term LBW increased approximately 5% per interquartile range increase in entire pregnancy exposures to several correlated traffic pollutants: LUR measures of NO, NO2, and NOx, elemental carbon, and PM2.5 from diesel and gasoline combustion and paved road dust (geological PM2.5).
  
  
  CONCLUSIONS
  These analyses provide additional evidence of the potential impact of traffic-related air pollution on fetal growth. Particles from traffic sources should be a focus of future studies.
authors.affiliation: Department of Epidemiology, School of Public Health, University of California-Los Angeles, 650 Charles E. Young Dr., Los Angeles, CA 90095, USA. mwilhelm@ucla.edu
authors.forename: Michelle
authors.initials: M
authors.lastname: Wilhelm
authors.forename: Jo Kay
authors.initials: JK
authors.lastname: Ghosh
authors.forename: Jason
authors.initials: J
authors.lastname: Su
authors.forename: Myles
authors.initials: M
authors.lastname: Cockburn
authors.forename: Michael
authors.initials: M
authors.lastname: Jerrett
authors.forename: Beate
authors.initials: B
authors.lastname: Ritz
mesh_terms: D000393:Air Pollutants / Q000032:analysis / Q000633:toxicity*; D000397:Air Pollution / Q000032:analysis; D004784:Environmental Monitoring; D005260:Female; D047109:Fetal Development / Q000187:drug effects*; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D015141:Los Angeles; D008297:Male; D018811:Maternal Exposure; D011247:Pregnancy; D001335:Vehicle Emissions / Q000032:analysis / Q000633:toxicity*
chemical_list: D000393:Air Pollutants; D001335:Vehicle Emissions