London, Aug 31 (IANS): Over 50,000 people die each year due to air pollution in Britain, a research team from Bristol reported ahead of a debate on Wednesday.

Cars, buses and freight trucks are the principal cause of air pollution in over 95 per cent of legally-designated air quality management areas in Britain, Xinhua news agency cited the study as saying.

Tim Chatterton and Graham Parkhurst from the University of the West of England in Bristol said transport planning in Britain was not sufficiently taking into account the environmental impacts of transport choices.

The two academics looked at policy and practice activities since a parliamentary environment act in 1995 committed Britain to improving air quality to internationally accepted standards.

Measurements in the real environment show that little improvement has been achieved in the past two decades, the study said.

The researchers carried out a review to identify the underlying reasons why air pollution concentrations from road transport in Britain have shown little to-no reduction over the last 21 years.

The study claimed that transport planners in Britain were not taking the environmental impacts of transport choices sufficiently into account.

"Air pollution is perhaps the grossest manifestation of a general failure of Britain's transport planning to take the environmental impacts of transport choices sufficiently into account," Parkhurst said.

"Insufficient relevant priority has been given within the sector responsible for most relevant emissions -- transport policy and planning -- which has instead prioritised safety and economic growth."

The academics said their study identifies a strategic policy tone which continues to signal and provide for the private car as central to national transport policy.

Households in poorer areas of Britain's towns and cities tend to be exposed to much higher levels of air pollution, even though they contribute much less to the traffic pollution principally through driving less.