The local Lib Dems have welcomed the latest national plans to improve air quality, which may see the most polluting vehicles - usually buses and lorries - charged for entering town and city centres.
MPs on the Environment, Food and Rural Affairs select committee are calling for "new clean air zones”, otherwise known as low emission zones, in dozens of English towns and cities to “cut the risk of cardiac, respiratory and other diseases".
Last year the Government proposed five low emission zones – in Birmingham, Leeds, Nottingham, Derby and Southampton – which will see charges for old diesel lorries, vans and taxis by 2020
At the latest Full Council in March the Lib Dems' motion that called on the Mayor to introduce a Low Emission Zone was passed with cross-party support.
Dr Mark Wright, the Lib Dem candidate for Harbourside ward in the local elections, was the first councillor to call for a Low Emission Zone in the city centre, over three years ago. He said:
"There is strong evidence that current levels of air pollution in our city is causing significant numbers of serious health impacts to Bristolians. A Low Emission Zone could make a significant contribution to improving air quality and would help Bristol meet the UK and EU air quality targets.
"Only last year Bristol was celebrating being the European Green Capital of Europe. Other cities are taking this issue very seriously but there has been no urgency or will from the current regime to progress things further.
"Whoever is in power after 5th May; the time for talking is over, the time for action is now. Let's do the decent thing and let's get on with it."
Lib Dem mayoral candidate Dr Kay Barnard added:
"There are hundreds of Low Emission Zones throughout Europe and they have proven to be successful in improving air quality. The air in Bristol has to be improved and we have to do something. That is why after years of campaigning for a Low Emission Zone by the local Lib Dems here in Bristol, I will make it a reality if I am elected as Mayor of the city."