" Hayfever is increasingly being caused by pollen spread by diesel cars, a study has found. Worsening traffic congestion is adding to the problem with "urban hayfever" affecting 60 per cent of city dwellers. The pollen attaches itself to the heavy exhaust particles from diesel cars which are particularly adept at carrying it deep into airways, according to Dr Adrian Morris. As diesel accounts for 40 per cent of new cars sold, the problem is increasing rapidly.  Dr Morris, allergy expert for Kleenex tissues, said: 'It used to be hay that pollen would bind itself to but what most people don't know is that today it is diesel exhaust residue on cars.' "  To read the article please click here.