Air Pollution and Postneonatal Infant Mortality in the United States, 1999-2002

Environmental Health Perspectives Volume 116, Number 1, January 2008

 

Air Pollution and Postneonatal Infant Mortality in the United States, 1999–2002

http://www.ehponline.org/docs/2007/10370/abstract.html

Tracey J. Woodruff,^1* Lyndsey A. Darrow,² and Jennifer D. Parker³

¹Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Francisco, California, USA; ²Department of Epidemiology, Emory University, Atlanta, Georgia, USA; ³National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland, USA

Abstract
Objective: Our goal was to evaluate the relationship between cause-specific postneonatal infant mortality and chronic early-life exposure to particulate matter and gaseous air pollutants across the United States.

Methods: We linked county-specific monitoring data for particles with aerodiameter of ≤ 2.5 µm (PM_2.5) and ≤ 10 µm (PM₁₀) , ozone, sulfur dioxide, and carbon monoxide to birth and death records for infants born from 1999 to 2002 in U.S. counties with > 250,000 residents. For each infant, we calculated the average concentration of each pollutant over the first 2 months of life. We used logistic generalized estimating equations to estimate odds ratios of postneonatal mortality for all causes, respiratory causes, sudden infant death syndrome (SIDS) , and all other causes for each pollutant, controlling for individual maternal factors (race, marital status, education, age, and primiparity) , percentage of county population below poverty, region, birth month, birth year, and other pollutants. This analysis includes about 3.5 million births, with 6,639 postneonatal infant deaths.

Results: After adjustment for demographic and other factors and for other pollutants, we found adjusted odds ratios of 1.16 [95% confidence interval (CI) , 1.06–1.27] for a 10-µg/m³ increase in PM₁₀ for respiratory causes and 1.20 (95% CI, 1.09–1.32) for a 10-ppb increase in ozone and deaths from SIDS. We did not find relationships with other pollutants and for other causes of death (control category) .

Conclusions: This study supports particulate matter air pollution being a risk factor for respiratory-related postneonatal mortality and suggests that ozone may be associated with SIDS in the United States.

Key words: carbon monoxide, ozone, particulate matter air pollution, postneonatal infant mortality, respiratory-related deaths, sudden infant death syndrome, sulfur dioxide. Environ Health Perspect 116:110–115 (2008) . doi:10.1289/ehp.10370 available via http://dx.doi.org/ [Online 24 October 2007]