Exhaust fumes from diesel engines do cause cancer, according to the World Health Organization (WHO).
The International Agency for Research on Cancer, a part of the World Health Organization, had previously said that diesel exhausts probably cause cancer in humans.
The panel of experts have now concluded that exhausts are definitely a cause of lung cancer and may also cause tumours in the bladder.
It based the findings on research in high-risk workers such as miners, railway workers and truck drivers. It is thought that people working in these industries have a 40% increased risk of developing lung cancer. However, the expert panel said everyone should try to reduce their exposure to diesel exhaust fumes.
Dr Christopher Portier, who led the assessment, said: “The scientific evidence was compelling and the Working Group's conclusion was unanimous, diesel engine exhaust causes lung cancer in humans.”