The Department for Environment, Food and Rural Affairs (Defra) said it expects areas of west Scotland to record higher than normal levels, but that it is due to clear by tomorrow.
The warning came as Defra revealed air pollution in parts of England had already reached dangerously high levels in the past 24 hours, including in rural areas of south-east England and East Anglia’s towns and cities.
The elderly and people with health problems living in affected areas have been warned to take particular care over the coming days.
Those with lung and heart conditions should avoid strenuous activity outdoors while people suffering symptoms such as sore eyes, coughs and sore throats, should cut down the amount of time they spend outside, health experts said. Asthmatics could also be prone to attacks over the next few days.
Defra said some areas were expected to reach “very high” levels of air pollution this month.
The advice, from Public Health England (PHE), Asthma UK and Defra came after a warning that parts of England were experiencing the highest level of air pollution recorded.
Defra ranks air pollution from one to ten. Across most of England, moderate to high air pollution levels were being recorded, with level ten – “very high” – found in parts of East Anglia and the East Midlands.
Today, high levels are forecast for East Anglia, the Midlands, Lincolnshire, eastern and northern parts of Wales.
The department warned that high pollution levels will move north over much of coastal north-west England, to south-west Scotland and the north-east of Northern Ireland.
The problem has been caused by a combination of light south-easterly winds, the continental airflow and dust being blown up from the Sahara desert.
Frank Kelly, professor of environmental health at King’s College London, said: “The tiny particles we take into our bodies with each breath cause immediate problems for some individuals and contribute to longer-term problems for most of us in the form of heart disease and stroke.”
Dr Helen Dacre, a meteorologist at the University of Reading, said: “The problem is likely to be particularly bad because weather conditions have conspired to create a ‘perfect storm’ for air pollution.”