A study in Bradford has linked healthcare attendances for breathing difficulties to breaches in daily air pollution limits and revealed that the delayed impact of exposure to pollution was previously underestimated.
The research found that patients were still suffering from the impact of pollutants up to 100 days after exposure.
It also revealed that air quality in Bradford exceeded recommended levels 157 days a year, or 43% of the time.
Data was analysed from more than 120,000 GP and A&E attendances for respiratory problems over four years in Bradford.
The condition of up to 35% of patients seeing a GP and 49% of those attending A&E because of breathing difficulties was linked to days when nitrogen dioxide was above recommended levels set by the World Health Organisation.
Professor Rosie McEachan, director of the study, said: ‘Some 500 people die in Bradford each year from respiratory disease and we know that air pollution is a contributory factor.
‘We think previous research may have underestimated the impact of pollution on health care use, as it mainly focused on what happens immediately – on the day of the high pollution.’
The study ‘broke new ground’ in assessing the impacts of pollution that may only present later, Professor McEachan said.
The research follows the launch of Bradford’s clean air zone in September last year, which was ‘watered down’ by the city council to the point where just 4% of vehicles would be charged.