POLLUTION is making Oxford city centre filthier than ever, according to shock new findings.

Experiments using a new type of monitor devised by scientists at Harwell count small particles in the atmosphere.

AEA Technology's device, first tried at Carfax last year, is now being put into the city centre for several more weeks.

Rhonda Riachi, chairman of the city council's health and environment committee, said: "We're monitoring something we've never had data on before. Early evidence suggests it's worse than we thought but we now need to verify this. The very fine particles are thought to be able to cause heart attacks."

Because the equipment is so new, there are so far no comparisons of Oxford's pollution levels with those of other British cities.

Ms Riachi added: "The benefit is that it's possible to sort out traffic pollution from other forms of pollution."

Both county and city councils have drawn up far-reaching plans to cut traffic in Oxford by about ten per cent.

A public inquiry into the Oxford Transport Strategy - which includes pedestrianising Cornmarket Street and Broad Street and keeping cars out of High Street - is currently being held at Oxford Town Hall.

Peter Allen, head of environmental health at Oxford City Council, said: "I expect to find there's a significant level of particles in the air - given the amount of traffic it is logical that would be so.

"The prototype gave an indication that's so."

He added: "It's believed that the fine particles can cause more damage to health and can aggravate the respiratory system."

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