UP to 250 people are dying early every year in Islington because of air pollution.

The borough has the sixth-highest average levels of dangerous airborne particles linked with premature deaths from heart attacks, strokes and respiratory problems, according to a study by the Mayor of London.

Experts also say children living within 500 metres of busy streets, such as Holloway Road and Upper Street, can end up with lungs around 15 per cent smaller than normal.

Former Islington councillor Baroness Sarah Ludford, who is now a Liberal Democrat MEP for London, has branded the shocking levels of pollution a “terrible health threat” – and has demanded urgent action.

Baroness Ludford, who lives near the traffic-choked Angel junction, said: “It’s shocking there are any premature deaths at all through air pollution. We have got to put our shoulder into this. I won’t be satisfied until there are no premature deaths. This really is an emergency.”

The report said there were probably 100 premature deaths a year in Islington partly caused by long-term exposure to the most dangerous pollutants – known as PM2.5 particles which come from car exhaust fumes. And it said the total deaths could even be as high as 183.

Islington Green Party spokeswoman Emma Dixon said her party’s estimates put the annual number of deaths even higher at 250.

She said: “Air pollution is killing people and Islington has particularly poor air quality. Even one death a year is too many – 250 is terrible.”

Islington also exceeded legal limits imposed by the EU on the amount of nitrogen dioxide in the air last year, with levels at a monitoring station in Holloway Road, Holloway, nearly 50 per cent over the threshold. Nitrogen dioxide is linked with asthma and breathing problems.

The majority of people dying prematurely are aged 60 or older, according to Simon Birkett, the director of the Clean Air in London campaign – but children are also put at great risk by poor air quality.

Mr Birkett added: “Islington is one of the most polluted boroughs. Older people are dying up to 11-and-a-half years early and children’s lungs are being threatened. There’s no safe level for exposure to these particles and everyone is affected.”

Clean Air in London puts the likely number of early deaths across London at up to 8,000 a year.

Eighty per cent of the PM2.5 particles are released by road traffic, particularly diesel fumes, while construction work and gas boilers are also a problem.

Islington Council has been criticised for taking a step in the wrong direction with its controversial new “roamer” parking scheme, which allows drivers with resident parking permits to park anywhere in the borough between 11am and 3pm.

Ms Dixon said: “We’re really worried about roamer parking because it encourages more short journeys, which will increase traffic and emissions. The council has to send the right message to residents but right now it’s sending utterly the wrong message – it is encouraging people to drive around.”

Councillor Paul Smith, Islington Council’s Labour executive member for environment, said: “We want to make things easier for ordinary working people in tough times, that’s why we’re allowing people to make essential trips in the middle of the day without them paying for visitor vouchers.

“The overwhelming majority of people think that being able to visit friends and family or shop at local businesses without paying for visitor vouchers is a good thing.”

The European Commission will this month decide whether to take the UK Government to court over London’s pollution levels, which are above legal levels imposed by the EU.