Assessing the Influence of Traffic-related Air Pollution on Risk of Term Low Birth Weight on the Basis of Land-Use-based Regression Models and Measures of Air Toxics

• Published in: American journal of epidemiology Vol. 175; no. 12; pp. 1262 - 1274
• Main Authors: GHOSH, Jo Kay C, WILHELM, Michelle, SU, Jason, GOLDBERG, Daniel, COCKBURN, Myles, JERRETT, Michael, RITZ, Beate
• Format: Journal Article
• Language: English
• Published: Cary, NC Oxford University Press 15-06-2012; Oxford Publishing Limited (England)
• Subjects: Adult; Air Pollutants - analysis; Air Pollutants - toxicity; Air pollution; Air Pollution - adverse effects; Air Pollution - analysis; Babies; Biological and medical sciences; Birth Certificates; Birth weight; Diseases of mother, fetus and pregnancy; Environment. Living conditions; Epidemiology; Female; General aspects; Geographic Information Systems; Gynecology. Andrology. Obstetrics; Humans; Hydrocarbons; Infant, Low Birth Weight; Infant, Newborn; Logistic Models; Los Angeles; Maternal Exposure - adverse effects; Medical sciences; Miscellaneous; Models, Theoretical; Original Contributions; Pregnancy; Pregnancy. Fetus. Placenta; Public health. Hygiene; Public health. Hygiene-occupational medicine; Regression Analysis; Risk Factors; Seasons; Toxicity; Vehicle Emissions - analysis; Vehicle Emissions - toxicity; Los Angeles; USA, California, Los Angeles Cty; Pregnancy disorders; Infant; Risk; Epidemiology; Growth retardation; Health and environment; Female; fetal growth retardation; Woman; Public health; Human; Evaluation; Hydrocarbon; hydrocarbons; Use; Low birth weight; Air; aromatic; Pregnancy; Newborn diseases; Fetal development; Prematurity; Regression model; Benzene; Risk factor; Air pollution; Road traffic
• ISSN: 0002-9262; 1476-6256
• DOI: 10.1093/aje/kwr469

Few studies have examined associations of birth outcomes with toxic air pollutants (air toxics) in traffic exhaust. This study included 8,181 term low birth weight (LBW) children and 370,922 term normal-weight children born between January 1, 1995, and December 31, 2006, to women residing within 5 miles (8 km) of an air toxics monitoring station in Los Angeles County, California. Additionally, land-use-based regression (LUR)-modeled estimates of levels of nitric oxide, nitrogen dioxide, and nitrogen oxides were used to assess the influence of small-area variations in traffic pollution. The authors examined associations with term LBW (≥37 weeks' completed gestation and birth weight <2,500 g) using logistic regression adjusted for maternal age, race/ethnicity, education, parity, infant gestational age, and gestational age squared. Odds of term LBW increased 2%-5% (95% confidence intervals ranged from 1.00 to 1.09) per interquartile-range increase in LUR-modeled estimates and monitoring-based air toxics exposure estimates in the entire pregnancy, the third trimester, and the last month of pregnancy. Models stratified by monitoring station (to investigate air toxics associations based solely on temporal variations) resulted in 2%-5% increased odds per interquartile-range increase in third-trimester benzene, toluene, ethyl benzene, and xylene exposures, with some confidence intervals containing the null value. This analysis highlights the importance of both spatial and temporal contributions to air pollution in epidemiologic birth outcome studies.