The UK has been ranked 29th worst out of 194 countries measuring the rate of children getting asthma from traffic pollution with results based on nitrogen dioxide concentration and asthma incidence.
Four million children around the world develop asthma each year because of road traffic pollution, the study published in The Lancet Planetary Health has estimated.
Exposure to nitrogen dioxide, largely from road transport, is thought to be behind the nearly 40 thousand new cases in the UK.
Cases of childhood asthma have increased steadily since the 1950s, making it the most common disease among children worldwide, although experts are divided as to what actually causes people to develop the condition. However, exposure to air pollution in childhood increases the risk by damaging the lungs.
While various pollutants in traffic air pollution could be responsible, previous research suggests exposure to nitrogen dioxide could be key.
Using global data on nitrogen dioxide concentration and asthma incidence, researchers estimated the number of new cases which could be related to traffic pollution.
In the UK, the number of children found to have developed traffic related asthma was 38,000 incidences and an incidence rate of 280 which was 19 per cent of total incidences.
Results from Kenya were much lower with 14,000 incidences. The country’s incidence rate (per 100k children) was 64 and 4.1 percent of total incidences.