In a study this year, fetal exposure to high levels of polycyclic aromatic hydrocarbons (PAHs), common in automobile exhaust and coal-burning fuel, were shown to result in lower I.Q. for kids by age five.
Dr. Michal Jerrett of the School of Public
Health, University of California, Berkeley said: "Children exposed to
prenatal or in-utero air pollution from traffic oftentimes have lower birth
weights, somewhat smaller head circumferences, and a number of adverse
For more on PAH see Agency for Toxic Substances and Disease Registry.