Updated

For the first time, European researchers have confirmed poor air quality due to congested road traffic is linked to kids’ asthma, the Los Angeles Times reported.

A study, published online in the European Respiratory Journal, found 14 percent of childhood asthma cases were attributed to nearby traffic pollution, according to the newspaper.

Researchers looked at children’s health in 10 different cities to come up with the conclusion, and it’s the first time a straightforward link has connected exhaust and an increased risk for asthma.

Past studies have said traffic pollution can trigger asthma symptoms – but it wasn’t the cause.

“In light of all the existing epidemiological studies showing that road-traffic contributes to the onset of disease in children, we must consider these results to improve policy-making and urban planning,” Dr. Laura Perez of the Swiss Tropical and Public Health Institute said in the Times.

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