Asthma is a chronic respiratory disease characterized by airway inflammation and constriction, leading to breathing difficulties, coughing, and wheezing. It remains one of the most prevalent chronic illnesses among children, driving a significant number of emergency department visits annually. Importantly, asthma limits participation in sports and other activities that are essential for children’s mental and physical well‑being.
Traffic‑related air pollution not only triggers asthma attacks but also contributes to the initial development of the disease in children. Fumes from gasoline‑powered vehicles release nitrogen dioxide and other irritants that inflame the lungs.
In Canada and the United States, automobiles are the largest contributors to climate‑warming pollution. Transportation accounts for roughly 25 % of total greenhouse gas emissions, with passenger cars responsible for the majority.
To curb climate change and improve air quality, many U.S. states have enacted Zero‑Emission Vehicle (ZEV) mandates, obligating automakers to sell a minimum number of electric vehicles each year. ZEVs encompass fully electric cars, plug‑in hybrids, and fuel‑cell vehicles.
Canada has adopted a parallel approach. The federal government has set a target that 100 % of new vehicle sales be ZEVs by 2035.
How do these policies translate into real health outcomes for children? Researchers at the University of Toronto—led by Dr. Steve Easterbrook, director of the School of the Environment—examined the relationship between electric and gasoline vehicle sales across U.S. states and childhood asthma incidence from 2013 to 2019. Their study was published in Environmental Research.
The findings suggest that if one in five new cars sold were electric, the number of asthma cases attributable to vehicle emissions would decline dramatically. The study underscores the critical role of reducing emissions in protecting lung health.
However, the authors caution that the health benefits hinge on several factors. Electric vehicles must replace gasoline cars rather than add to the fleet. Equitable access to ZEVs beyond states with mandates is essential, as automakers may prioritize those markets. Moreover, the electricity powering EVs must come from clean sources to avoid shifting pollution to power plants.
The team also calls for improved battery recycling and responsible material sourcing to ensure that the transition to electric mobility delivers comprehensive environmental and public‑health gains.
In sum, replacing gasoline vehicles with electric ones can markedly reduce exhaust‑related air pollution, lower childhood asthma rates, and mitigate other pollution‑driven respiratory conditions such as emphysema.
