Why the air inside your car may be more harmful to your child than outside

Air pollution is bad when you’re outdoors, but scientists are warning that it’s even worse inside cars — and especially for children.

In an article for The Guardian, a British scientist described vehicles as “boxes collecting toxic gases,” explaining that they collect and hold harmful chemicals from the road. David King, who advises the British Lung Foundation, said children sitting in back seats are at higher risk of being “exposed to dangerous levels” of pollution because outside air travels to the rear of cars.

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Air pollution also has the most adverse health effects on children because their bodies aren’t fully developed, according to the World Health Organization. That means “higher doses of pollutants” can reach their lungs and stunt function, or cause issues such as asthma.

Miriam Diamond, an Earth sciences professor at the University of Toronto, says the firewall between a car’s engine and interior isn’t as thick as many people assume, which leads to emissions leaking inside the car. She adds that closed windows don’t prevent outside pollution from seeping inside.

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“It’s not totally shut because then you would suffocate,” she says.

But how do parents get children from one place to another without exposing them to air pollution inside cars? Diamond says it’s all about getting outside.

“I hate to say this, but one option is to get out of the car and walk,” she says, acknowledging the move requires parents to slow down, which isn’t always easy.

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If that’s not possible, Diamond advises buying a hybrid or electric vehicle that’s as small as possible.

“The bigger the car, the more fuel,” she says.

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There are long-term solutions to the problem as well. Diamond says they begin with investing in cleaner public transit.

“It’s misguided to go down the route of electrifying private vehicles,” she says, explaining that won’t solve gridlock or promote a non-sedentary lifestyle.