In previous investigations, we and others
have linked exposure to ambient air pollution
with lung-function impairment in children.
1-8 Reduced lung function in children has
been associated with an increased risk of asthma.
9 In addition, the adverse effects of air pollution
on the lungs in childhood can potentially
have long-term effects: lung function lower than
the predicted value for a healthy adult has been
found to be associated with an increased risk of
cardiovascular disease and increased mortality
rate.10-12 Although progress has been made throughout
the United States to reduce outdoor levels of
several air pollutants, it is not known whether
these reductions have been associated with improvements
in children’s respiratory health.