Three-out-of-four GP surgeries in Northampton town centre is on a road exceeding safe air-pollution limits, a report has claimed.
There are 27 GPs and three hospitals in Northampton - and the British Lung Association says many of them are exposed to excessive levels of pollution.
The charity has published research into the levels of fine particulate matter (PM2.5) near every GP and hospital in the UK.
They found 2,220 GPs and 248 hospitals are exposed to more than the World Health Organisation's limit of 10ug/m3 (micrograms per metre cubed) - which includes every practice in the town centre.
The report reads: "The Government urgently needs to put in place the right measures to ensure that no one breathes dirty air, and adopt the World Health Organisation’s recommended limit into UK law through the upcoming Environment Bill."
No patient, doctor, nurse or GP should be exposed to such a preventable cause of ill health and early death.
PM2.5 are minuscule particles invisible to the naked eye that are small enough to pass through the lungs, and enter the bloodstream.
The British Lung Association say the pollutant can aggravate existing conditions, and increase the chance of developing a lung condition.
It comes after a report by the borough council in 2016 found "one-in-20 deaths" in the town could be linked to air pollution. The town's Harlestone Road was also named fifth on a list of the most polluted roads in the East Midlands.
Meanwhile, a council plan in underway to create an 'air-quality management area' for the entire town centre, and create more charging points for electric taxis.
Northampton Borough Council has been contacted for a comment.