Relatively healthy individuals may experience itchy eyes and sore throats but vulnerable people are being told to follow their doctor's or health professional's advice and be cautious.
The smog is formed as air is drawn from the continent and 'particulate matter', small particles and chemicals thrown into the air from motor vehicles and fires, causes health problems. "Levels in London this morning were three-times the recommended EU limit" and expected to worsen in the next 24 hours.
Opinion: As a person who quit smoking more than 30 years ago I have long argued that it is no good simply blaming smoking for various health issues as pollution from vehicles affects us all. In the case of this predicted smog continental air and pollution will endanger us all.