High levels of air pollution are expected in the South this week, posing a health risk to medically vulnerable members of the public.

Defra – the Department for Environment, Food and Rural Affairs – uses a 10-point scale to measure air quality, with 1 being a ‘low’ risk of air pollution, and 10 ‘very high’. Bournemouth today rates as eight along with Christchurch, while Poole rates as seven. 

On Thursday and Friday, Bournemouth, Poole and Christchurch are expected to rate as level three as the smog moves away.

The high levels of air pollution have been caused by a combination of a South Easterly wind, European emissions and dust from the Sahara desert, creating smog in parts of the South and East Anglia.

And as a consequence, the health of those with existing medical problems is at risk.

Dr David Phillips, director of Public Health Dorset, said: "While the highest pollution levels seem to be in East Anglia and East Midlands, we are expecting moderate to high levels in Dorset today. Most people will not be affected by this but anyone with known heart or lung problems should avoid significant physical exertion while levels are high and people with asthma may need to use their inhaler more often. Pollution levels are expected to return to normal tomorrow."

Dr Sotiris Vardoulakis of Public Health England said: “Whilst most people will not be affected by short term peaks in air pollution, some individuals, particularly vulnerable groups such as those with existing heart or lung conditions, may experience increased symptoms.”

He added that people with asthma may find they need to use their inhaler more often.

Adults and children with lung problems, adults with heart problems, and the elderly are advised to reduce strenuous physical exercise outside, particularly if they experience symptoms.

Likely physical symptoms of air pollution include sore eyes, a cough or a sore throat.

The smog will spread across the South during the course of today and tomorrow, but is expected to have gone by Friday, when air pollution levels will drop to a 3 on Defra’s 10-point air pollution scale.

The high air pollution emphasises more than ever the need for renewable energy, according to East Dorset Friends of the Earth, who claim that the use of fossil fuels has long contributed to air pollution.