Largest study of kind shows link between outdoor particulate pollution, impaired fetal growth.
Mothers who are exposed to particulate air pollution of the type emitted by vehicles, urban heating and coal power plants are significantly more likely to bear children of low birth weight, according to an international study led by researchers from UC San Francisco and the Centers for Disease Control and Prevention (CDC).
The study, the largest of its kind ever performed, analyzed data collected from more than 3 million births in nine nations at 14 sites in North America, South America, Europe, Asia and Australia.
Co-principal investigator Tracey J. Woodruff, Ph.D., M.P.H., professor of obstetrics and gynecology and reproductive sciences at UCSF, along with Jennifer Parker, Ph.D., of the National Center for Health Statistics, CDC, found that at sites worldwide, the higher the pollution rate, the greater the rate of low birth weight.
Low birth weight (a weight below 2,500 grams or 5.5 pounds) is associated with serious health consequences, including increased risk of postnatal morbidity and mortality and chronic health problems in later life, noted lead author Payam Dadvand, M.D., Ph.D., of the Centre for Research in Environmental Epidemiology (CREAL) in Barcelona, Spain.
In the study, published today (Feb. 6) in the journal Environmental Health Perspectives, the team assessed data collected from research centers in the International Collaboration on Air Pollution and Pregnancy Outcomes, an international research collaborative established in 2007 to study the effects of pollution on pregnancy outcomes. Most of the data assessed was collected during the mid-1990s to the late 2000s, and in some cases, earlier.
“What’s significant is that these are air pollution levels to which practically everyone in the world is commonly exposed,” said Woodruff. “These microscopic particles, which are smaller than the width of a human hair, are in the air that we all breathe.”
Co-authors of the paper included Bill M. Jesdale and Rachel Morello-Frosch of UC Berkeley.