Lung health checks were cancelled in Blackpool as high levels of pollution returned to the North West.
The checks were part of a week-long All Together Now roadshow organised by the local NHS, Blackpool Council and Blackpool Football Club.
A mobile unit has been visiting local supermarkets all week, offering lung and blood pressure checks and stop smoking advice.
But organisers yesterday cancelled the lung checks when the roadshow arrived at Morrisons supermarket on Squires Gate Lane.
They felt it would be inappropriate to ask people to blow into a machine when pollution levels were high.
A sign posted at the unit said: ‘Sorry, we’re unable to perform lung checks today because of air pollution. Hopefully we will be able to offer them tomorrow’.
Air quality hit the national headlines on Wednesday when high levels of pollution were recorded in London, the South East and the Midlands.
The smog-like conditions have been attributed to local and continental pollution, and dust from the Sahara Desert.
High pollution levels were recorded in the North West on Monday. They dropped to low levels on Tuesday, rose again on Wednesday and returned to high levels yesterday, with hazy skies over Blackpool.
A spokesman for Blackpool Teaching Hospitals NHS Foundation Trust said that the Whitegate Health Centre, a walk-in service on Whitegate Drive, Blackpool, had noticed a slight increase in the number of people coming in with respiratory problems.
North West Ambulance Service reported an increase in call-outs to people with breathing problems.
It had 858 call-outs from Wednesday March 26 to Saturday March 29, rising to 985 call-outs from Sunday March 30 to Wednesday April 2.
People with lung and heart problems are being told to avoid heavy outdoor exercise.