Figure 11: Unscheduled daily asthma medication use by children with asthma is associated with summertime ozone air pollution. Use of inhaled beta-adrenergic agonist medication to alleviate asthma aggravation is plotted against ozone concentrations during summer asthma camps conducted for children 7 to 13 years old, during the last week of June, 1991 through 1993, in the Connecticut River Valley, downwind of New York City. Each child's normal physician-prescribed medications were maintained throughout each week. An increase in the 1-hour daily maximal ozone concentration from 84 to 160 ppb was significantly associated with increased unscheduled medications administered per day. Source: Thurston et al., 1997