A “toxic stew” of pollution is due to hit Fife, according to Friends of the Earth Scotland.
A warning to those with heart and lung problems has gone out as the organisation warned of “a dangerous air pollution episode” expected to descend on many parts of the central belt.
The scenario is anticipated to unfold on Thursday and peak on Friday, with some areas still affected on Saturday.
However, the situation won’t reach the ‘red alert’ levels of smog experienced by the likes of Beijing.
Toxic levels are expected to smash World Health Organisation and Scottish regulatory safety standards in 15 local authority areas, including Fife and Perth and Kinross.
Air pollution campaigner Emilia Hanna said pollution was expected to blow in from the east and combine with the heavy air pollution pouring out of car and lorry exhausts.
“The weather is expected to be still and calm on Friday, which means that the air pollution will have nowhere to go, creating dangerous conditions with our air much more damaging than usual.
“People with lung or heart problems and older people will be especially vulnerable to this toxic stew.
“The expected pollution levels will be exceptionally high and in some places will be potentially dangerous for people who are otherwise healthy as well as at risk individuals.”
Tomorrow adults and children with lung problems, and adults with heart problems, should curb strenuous exertion particularly outdoors and if they experience symptoms. Asthma sufferers should ensure they carry their inhalers. Older people should also reduce physical exertion and anyone experiencing discomfort such as sore eyes, cough or sore throat should reduce activity.
The same advice for adults and children with lung problems, and adults with heart problems who experience symptoms applies for Perth and Kinross.
Friends of the Earth is calling on the Government to take concerted action to tackle Scotland’s air pollution problem.
Emilia added: “The Government should advise people to avoid driving and adding to the problem.”