The particles can cause coughing, wheezing and shortness of breath

The Chartered Society of Physiotherapy (CSP) looked at levels of PM10 picked up at various points around the UK.

London's Marylebone Road and Camden were worst, with Port Talbot in south Wales and Bury in Lancashire also in the top five pollution hotspots.

World Health Organisation experts say there is no safe limit for PM10.

The pollutant consists of tiny solid or liquid particles of soot, dust, smoke, fumes and aerosols.

TOP 10 HOTSPOTS London Marylebone Road 43 micrograms/m3 Camden Kerbside 35 Port Talbot 31 Bury Roadside 30 Bradford Centre 27 Glasgow Kerbside 27 London A3 Roadside 27 London Hillingdon 27 Stockton-on-Tees Yarm 27 London Bloomsbury and London Harlington 26

The CSP said the pollutant could cause coughing, wheezing and shortness of breath.

The effects on those with lung diseases such as asthma, bronchitis and emphysema could be far more serious, respiratory physiotherapists warned.

The CSP said its analysis showed there were high levels across the UK, with an average of 23.3 micrograms per cubic metre of air (micrograms/m3).

The highest level was found on Marylebone Road, with 43 micrograms/m3, followed by Camden with 32 micrograms/m3.

'Worst air quality'

But the survey showed that many other parts of the UK had high levels of PM10, with five of the top 10 hotspots outside London.

The CSP's Grahame Pope said: "The government should accept the WHO position that there is no safe exposure limit.

"Local authorities should follow the Japanese example by banning these vehicles from built up areas."

London mayor Ken Livingstone said: "London has long-suffered the worst air quality in the country, with air pollution estimated to cause 1,600 premature deaths every year.