It's yet further evidence that pollution from cars and lorries shortens people's lives

Roger Higman, Friends of the Earth

These particles can be produced by industrial chimneys and car exhausts.

By comparing the levels of pollution in the area where each patient lived to the cause of death, the researchers discovered a striking link between certain illnesses and pollution.

The researchers found that the death rate from lung cancer increased by 8% for every increase of 10mcg of fine particulate matter per cubic metre.

There was also an increase in heart disease corresponding to the rise in levels of these key particles.

Lung disease has been blamed on pollution

Professor George Thurston, from the New York School of Medicine, who co-led the study, said: "This study is compelling because it involved hundreds of thousands of people in many cities across the US who were followed for almost two decades."

The study found that the risks of living in such heavily polluted areas did not approach those caused by a person smoking cigarettes.

However, it was comparable, said the researchers, with that faced by non-smokers exposed to second-hand smoke over an extended period.

Deadly diagnosis

Lung cancer is one of the hardest cancers to treat successfully.

Even with the latest drugs and treatments, only one in 10 people is alive five years after diagnosis - and in many parts of the UK, the survival rate is only half this or worse.

As a result, although it is not the most common cancer in the UK, it kills far more people than any other type.

Levels of fine particulate pollution have fallen away slightly over recent years, mainly due to cleaner burning car engines.

However, campaigners are still concerned that targets for particulate levels are regularly being exceeded both in major cities - and even certain busy streets in smaller towns.

Death toll

In 1998, an influential government committee on the effects of air pollution suggested that 10,000 people a year might be dying as a result of particulate pollution.

In addition to lung cancers and heart disease, it has been linked to asthma, and other lung and circulatory diseases.

Roger Higman, a transport campaigner at Friends of the Earth UK, said that the sheer scale of the US research should point the way to similar UK studies.

"It's yet further evidence that pollution from cars and lorries shortens people's lives - and exposes the government's failure to tackle this problem."

He called for more action to cut emissions from both industry and transport - and more schemes, such as the recently-approved congestion charge for inner London, to reduce road use in the worst-hit areas.