Scientists have found new evidence that prenatal exposure to air pollution may cause congenital heart defects. However, inconsistencies with past results make the finding less than definitive, the researchers say.
Epidemiologist Pauline Mendola of the Environmental Protection Agency in Research Triangle Park, N.C., and her collaborators compared pollution statistics and records of births between 1997 and 2000 in seven Texas counties. The researchers focused on the quality of the air that women were breathing during their first 2 months of pregnancy, which a 2002 study in California had linked to certain congenital defects of the heart, lip, and palate.
In Texas, women who'd been exposed early in their pregnancies to relatively high concentrations of carbon monoxide, sulfur dioxide, or particulate matter were more likely than other women to have babies with certain heart defects. As the California study had, the new report identified a tentative link between ozone exposu