Environment

How Scientists Discovered What Dirty Air Does to Kids’ Health

The landmark Children’s Health Study tracked thousands of children in California over many years—and transformed our understanding of air pollution’s harms.
A two-year-old girl receives nebulizer treatment in Beijing in 2015.Jason Lee/Reuters

The following is an excerpt from the new book Choked: Life and Breath in the Age of Air Pollution (University of Chicago Press, $27.50).

Across Southern California, in school gyms and libraries and lunchrooms, the children filed in, one by one, to put their lips around a plastic tube and blow with all their might. Thousands of them, year after year, in rich neighborhoods and poor ones, from the breezy towns along the Pacific coast to the hot, smoggy valley locals know as the Inland Empire.