Pollutants spewing from vehicles and power plants may be harmful to fetal brains, new evidence suggests. The study is the first to directly link delayed cognitive development in children to their mothers' exposure during pregnancy to common air pollutants called polycyclic aromatic hydrocarbons, or PAHs.
Earlier studies established a similar relationship between slowed neurological development and prenatal exposure to lead, says Frederica P. Perera, the Columbia University environmental health scientist who led the new study.
Last year, other researchers reported that secondhand cigarette smoke may also dull kids' wits (SN: 1/15/05, p. 37: Available to subscribers at Living in a Fog: Secondhand smoke may dull kids' wits). Such smoke also contains PAHs.
"These pollutants come largely from combustion of fossil fuels, including gasoline, diesel, and coal," Perera says. PAHs come in hundreds of chemical varieties, at least some of which are ca