Asthma among children — close to 67,000 new cases — is hitting home in 18 European countries because of small particulates contaminating the air, according to a new report. But a number of those cases could be prevented yearly if the particulates were reduced to appropriate levels.

This study is one of many about how air pollution affects human health. An important landmark study published in April revealed 4 million new asthma cases a year worldwide among ages 1 to 18 were because of levels of nitrogen dioxide in the air.

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The new research examined asthma diagnoses among more than 63.4 million children ages 1 to 14 and looked at components of toxic air, like fine particulates or PM2.5. Researchers also took note of nitrogen dioxide released by vehicles and other sources.

“A considerable proportion of childhood asthma is actually caused by air pollution, particularly PM2.5,” said co-author Mark Nieuwenhuijsen from the Barcelona Institute of Global Health.

Overall, the study suggests 66,600 new cases of asthma could be prevented annually by following World Health Organization guidelines: levels of PM2.5 should not exceed an annual average of 10 μg/m3, and levels of nitrogen dioxide should not exceed an annual average of 40 μg/m3. But the report said even this might not be enough. The authors believe there is no starting point to the impact of air pollution on human health.

“What is clear from our analysis is that current WHO standards are not strict enough to protect against many cases of childhood asthma,” Nieuwenhuijsen said. WHO guidelines are currently under review.

Susan Anenberg, a co-author of the related study published in April, said the latest research showed how damaging air pollution can be on public health.

“Almost no one on planet Earth breathes clean air,” Anenberg said. “The good news is that there are many ways to prevent children from getting asthma because of their air pollution exposure. Making it easier to cycle, walk or run to get places, for example, has many benefits for society — including improved air quality, increased physical activity and less climate-warming pollution.”

+ European Respiratory Journal

Via The Guardian

Image via David Holt