Children at greater risk from traffic pollution
25 June 2009

New research suggests children may be at greater risk from the microscopic particles in traffic pollution, than was previously thought, leaving them vulnerable to asthma.

The particles - so-called ‘particulates’ - are produced in vehicle exhaust and are far smaller than the width of a human hair.

Professor Jonathan Grigg from the Centre for Paediatrics at Barts and the London School of Medicine and Dentistry is leading a major London study which involves 203 children at 10 different schools. The children are taking part in various regular tests over several years, including one which encourages them to cough so the carbon content in their sputum can be analysed.

Interim findings from 149 children in the Tower Hamlets area show that the lung capacity of 8 and 9 year olds is 5% lower than the national average, and that many of them are at risk of a range of breathing conditions.

Similarly, research by Lancaster University shows that the particulate levels may be even worse than official figures show. The official data is gathered at automatic monitoring stations which typically sample air at a height of three metres - mainly to avoid the risk of vandalism.

But Professor Barbara Maher and her team have devised a new technique for measuring the magnetic response of particulates on roadside leaves - many of the particles contain fragments of metal. Analysing these particulates, the researchers have found that the pollution can be most intense at the height of many children.

Emily Humphreys, Policy & Information Manager at Asthma UK, said: ‘Research like this is really interesting, because it builds on what people with asthma have told us about the problems caused by pollution. We already know that pollution triggers symptoms in people who already have asthma: two thirds of people with asthma say that traffic fumes trigger their symptoms and 42% are put off from walking or shopping in congested areas.

‘Professor Grigg’s study further explores whether pollution also increases the risk of developing asthma. Asthma UK is keen to see further research into this area, as well as strong efforts by local and national government to reduce traffic pollution.’