Citing growing evidence of harm, advocates call for faster replacement of diesel school buses

Health and environmental advocates today called on communities, school boards and governments at every level to accelerate the electrification of school buses, replacing tens of thousands of diesel-powered school buses spewing toxic fumes that can seriously harm child health and interfere with learning.

Led by the Canadian Partnership for Children's Health and Environment (CPCHE), a coalition of 34 organizations made the goal of all-electric school bus fleets in Canada the central focus of this year's national Healthy Environments for Learning Day (April 27).

The joint call for urgent action by relevant decision-makers nationwide closely follows the publication in January of new scientific evidence from British Columbia that even "brief diesel exhaust exposure acutely impairs functional brain connectivity." While adult subjects were studied, the new research raises further concerns about impaired brain function and learning ability of children breathing diesel fumes.

Other research has warned that diesel exhaust may impede child neurodevelopment, spatial learning, attention and memory, and contributes to a myriad other physical and mental health problems (detailed below), as well as climate change.

"Faced with the existential threat posed by climate change and mounting scientific evidence of the harm to children caused by traffic-related air pollution, including diesel exhaust, more comprehensive and urgent action is needed to bring electric school bus transportation to all communities across Canada," the declaration says.

It underlines that "electric school buses are a viable solution that eliminates diesel bus emissions and exemplifies local action on climate change."

The majority of Canada's 50,000 school buses use diesel fuel. Each year, school buses make 792 million trips to carry roughly 2.2 million children to and from school.

Says CPCHE Executive Director Erica Phipps, "Buses operating close to schools mean that all children, not just those riding the buses, can be exposed to and affected by diesel exhaust."

"The financial savings achieved over time by switching to cleaner, more sustainable school transportation more than make up for the initial cost of an electric bus. By switching to electric school buses, we can help our children thrive physically and intellectually while protecting the environment for generations to come with a tangible, visible action on climate change."

CPCHE and its collaborators today called on all levels of government to:

• Accelerate the shift to all electric school bus fleets across Canada, through policy and funding measures that support electric bus procurement, operation and infrastructure
• Prioritize electric school bus adoption in communities facing disproportionate exposure to traffic-related air pollution
• Promote and celebrate the electric school bus as a way for children, families and communities to learn about and participate in climate action through the transition to zero-emission transportation in Canada

Says Dr. Phipps, "Given what we know about the child health effects of diesel exhaust and the risks posed by climate change, switching to an all electric school bus fleet should be an obvious choice nationwide to protect the health of children, now and into the future."

Along with the call for government action, the campaign is promoting videos and other educational resources to catalyze and inform local efforts to support the shift.

"The iconic yellow school bus transitioning to electric is a symbol of active hope," Dr. Phipps says. "It is an opportunity for students, educators and local communities to learn about and engage in a tangible action to protect the health of our children and the planet."

A litany of child health consequences

The World Health Organization has recognized diesel exhaust as a human carcinogen. And Health Canada's Human Health Risk Assessment concludes that exposure to diesel exhaust causes lung cancer and is linked to bladder cancer.

Health Canada has also documented a link between traffic-related air pollution (TRAP) and certain types of cancer including childhood leukemia and, in adults, breast cancer.

Acute and chronic exposures to diesel exhaust are linked to various harms including reduced lung function, inflammation of the airways, the risk of child asthma, chronic obstructive pulmonary disease, increased sensitivity to allergens, heart disease, arrhythmia, ischemia and myocardial infarction.

Toxicological research on diesel exhaust has also shown potential links to reproductive and developmental effects, and altered hormone levels and gene expression.

Today's declaration notes that children are more vulnerable than adults to the health effects of air pollution, including diesel exhaust, "because their bodies are growing, their lungs are developing and because they breathe in more air per kilogram of body weight."

Furthermore, "while Canadian data are limited, research shows that children in Canada who experience poverty, racialization and other forms of marginalization are often at greater risk because of disproportionate exposure to traffic-related air pollution."

Researchers have concluded that prenatal and early life exposures to traffic-related air pollution are likely implicated in autism spectrum disorder. Researchers have also found associations between TRAP and deficits in intelligence, memory, attention and behavior, as well as symptoms of anxiety and depression.

Furthermore, children can experience indirect barriers to learning as an impact of diesel exhaust. Asthma, for example, is the leading cause of school absenteeism and diesel emissions contribute to thousands of asthma symptom days and child acute bronchitis episodes across Canada every year.

Studies also show that substantial reductions in diesel emissions from school buses can contribute to decreases in childhood bronchitis and asthma cases, and lower diesel exposure may improve cognitive functioning.

Electric vs. diesel-powered buses:

While child health protection and climate action are clear benefits, initial challenges of shifting to electric school bus transportation can include the upfront costs of electric school bus models, the costs of charging stations and training for drivers and maintenance staff, and the shorter range of electric buses (though evolving battery technology is shrinking this difference with diesel vehicles).

While reliable operation in extreme cold weather is an often-cited concern, leading manufacturers of electric school buses guarantee their vehicles for operation in such conditions.