ST ALDATE’S in Oxford is the ninth most polluted street in England and the problem will get worse before it gets better.

The Government has revealed the Oxford city centre street has been included in its list of the 15 worst danger zones, with the annual average measurement for nitrogen oxide (NO2) in the road last year – 51mg/m3 – exceeding the European Union limit of 40mg.

The route also topped a second NO2 limit, because levels were above 200mg/m3 for three hours last year.

Last night, Oxfordshire County Council admitted the re-routing of more buses along St Aldate’s under its Transform Oxford project would lead to more pollution in the short term, but it said the situation would then improve through use of vehicles with cleaner exhaust emissions.

The EU has ordered Britain to cut NO2 levels on all roads by next year, or face unlimited daily fines.

In common with several other EU countries, the Government plans to request a five-year extension to the deadline, but if it is unsuccessful, it may be forced to take radical measures, including a road-pricing scheme.

If the EU took Britain to court and won, it could also allow residents to take legal action for poor health linked to air pollution.

Paul Cullen, the chairman of the Oxford Pedestrians’ Association, said: “It’s no surprise St Aldate’s and other central Oxford streets are so polluted.

“St Aldate’s is likely to become worse now that bus stops have been moved out of Queen Street, so there are more buses accelerating away from stops.

“It’s the crowded nature of the city centre and the narrow streets. There’s no place for motor traffic. I think in years to come we might look back and wonder how we ever allowed motor vehicles in the centre."

Richard Gibbs, of Cafe Loco, in St Aldate’s, said: “With the stops moving out of Queen Street I believe the number of buses has gone up by 50 per cent.”

Green Party city councillor Sushila Dhall insisted the situation could be improved. She added: “Transform Oxford is going to increase pollution in some areas and is too piecemeal an approach.”

However, an Oxford City Council spokesman said air quality was improving. Pollution peaked three years ago, she said, and a low-emission zone would be fully effective by 2014.

She added: “Air pollution levels have improved following other measures such as traffic restrictions and the High Street bus gate.”

The Oxford Bus Company and Stagecoach said they were investing in cleaner vehicles that met or were better than a Euro 5 emission standard.

Oxford Bus Company managing director Philip Kirk said: “We feel that we’re doing more than our share to keep emissions levels within the guidelines."

A county council spokesman said: “The council is encouraged by the recent investments made by local bus companies in meeting this standard.

“These innovations will result in steady reductions in air pollution in St Aldate’s and on other streets.

“The recent relocation of some buses will bring about only a very marginal and short-term increase, that will quite quickly be reversed, thanks to these innovations.”