Childhood asthma has been steadily rising since the 1950s and this mirrors the increase in the use of cars and lorries, which emit nitrogen dioxide, an air pollutant that can irritate the respiratory system and worsen any existing respiratory problems.
Air pollution is especially acute in the English town of Bradford, where researchers have been analysing air quality. Using new models that assess the impact of nitrogen oxides, researchers from the University of Leeds estimate that around 38 per cent of all cases of asthma in the town can be attributed to air pollution, and that 24 per cent were directly caused by car and lorry exhaust fumes.
Although asthma cases in the town are above the UK average, a similar pattern would probably be seen everywhere.
Lead researcher Dr Haneeen Khreis says it's the first time that the impact of vehicle pollution on children's asthma has been calculated, and it demonstrates that a vast number of cases could be prevented. Special walkways, traffic-free zones and the use of cleaner fuels could all be part of a national—and global—project to reduce cases.