Washington, Jan 6 (IANS): From Los Angeles to Mumbai, a traffic-related air pollutant drives nearly 2 million new cases of paediatric asthma every year, according to a new study.

Asthma is a chronic illness that causes inflammation of the lung's airways.

Researchers from George Washington University studied ground concentrations of nitrogen dioxide, or NO2 - a pollutant that comes from tailpipe vehicle emissions, power plants, and industrial sites. They tracked new cases of asthma that developed in children from 2000 until 2019 in more than 13,000 cities.

"Our study found that nitrogen dioxide puts children at risk of developing asthma and the problem is especially acute in urban areas," said Susan Anenberg, a co-lead author of the article and a professor of environmental and occupational health at the varsity.

"The findings suggest that clean air must be a critical part of strategies aimed at keeping children healthy," she added.

The findings, published in the journal Lancet Planetary Health, showed out of the estimated 1.85 million new paediatric asthma cases attributed to NO2 globally in 2019, two-thirds occurred in urban areas.

Despite the improvements in air quality in Europe and the US, dirty air, and particularly NO2 pollution, has been rising in South Asia, Sub-Saharan African and the Middle East.

Paediatric asthma cases linked to NO2 pollution represent a large public health burden for South Asia and Sub-Saharan Africa.

In a second study, published in the same journal, researchers from the varsity showed that 1.8 million excess deaths can be linked to urban air pollution in 2019 alone.

The team found that 86 per cent of adults and children living in cities around the world are exposed to a level of fine particulate matter that exceeds the guidelines set by the World Health Organisation.

"Reducing fossil fuel-powered transportation can help children and adults breathe easier and may pay big health dividends, such as fewer cases of pediatric asthma and excess deaths," Anenberg said. "At the same time, it would also reduce greenhouse gas emissions, leading to a healthier climate."