Air pollution from diesel traffic can worsen asthma, a chronic respiratory disease characterised by sudden recurring attacks of laboured breathing, chest constriction and coughing.
Diesel engines can generate more than 100 times more particles than petrol engines. The smaller the particle, the deeper it can be inhaled into the lungs and very small particles may even be absorbed into the bloodstream, BBC radio reported.
Researchers at London scientists examined the lung functions of about 60 people with mild or moderate asthma. The participants walked for two hours along Oxford Street in London, where only buses and taxis are allowed.
Then on a separate occasion they walked for two hours in traffic-free Hyde Park in the city. Lung function tests done before and after the walks showed a greater reduction in lung capacity and more inflammation in the lungs after the participants were exposed to diesel traffic than in the park.
The findings indicate the negative impact diesel fumes have on lungs, especially in asthmatics. There is a greater reduction in lung capacity of people with asthma when exposed to diesel traffic. However, a relation with petrol traffic and people without asthma could not be established.