In one of the first studies to examine air pollution in relation to infant and early childhood health, a UC Davis researcher has discovered a strong link between exposure to components of air pollution and acute bronchitis in preschoolers.

Those components -- polycyclic aromatic hydrocarbons, or PAHs -- contribute to air pollution from a variety of sources, including coal burning, autos, wood-burning stoves, tobacco smoke and grilling food.

Led by UC Davis environmental epidemiologist Irva Hertz-Picciotto, the Czech Early Childhood Health Study involved 1,133 children from birth to 4.5 years of age born in two districts of the Czech Republic from 1994 to 1998. One of those districts, Teplice, is known for high levels of air pollution. The other, Prachatice, has much lower levels.

Hertz-Picciotto and colleagues compared information on diagnoses of lower respiratory illnesses such as bronchitis, croup, pneumonia and asthma with detailed data on air quality.

"We saw the biggest impact on children old enough to play outside, while infants were affected but not quite as much," Hertz said.

-- Karen Finney, UC Davis Health System