A HEALTH alert has been sparked after high levels of potentially dangerous smog covered East Lancashire.

Experts said the toxic cloud could cause fatal asthma attacks and warned those with respiratory problems to stay indoors.

It is not expected to fully lift until Saturday and will remain at a 'moderate' level tomorrow, forecasters said.

MORE TOP STORIES:

Dr Tom Smith said: "If you have chronic lung disease or asthma, stay indoors until the smog has cleared.

"You should not be going out when there is a weather warning like this."

The Department for Environment, Food and Rural Affairs (Defra), said air pollution had blown in from Europe and mixed with home-grown smog to create the problem across Britain.

Dr Smith said the smog is made up of two components, the acidic chemical sulphur dioxide and small particles of soot-like material, which can both irritate the lungs.

He said: "It could put your lung into spasm, and that can have a rebound affect on your heart and your brain."

Lancashire Telegraph:

Lancashire Telegraph:

Asthma sufferers were also warned to carry their inhalers with them at all times.

However, officials said the smog does not pose a health threat for the general population.

Kay Boycott, chief executive of Asthma UK, said: "Two thirds of people with asthma find that air pollution makes their asthma worse, putting them at an increased risk of a potentially fatal asthma attack.

"When air pollution is high it's vital people with respiratory conditions including asthma check air pollution forecasts, carry their reliever inhaler with them at all times, and ensure that they are taking their preventer inhaler every day because this will help build resilience to asthma triggers like air pollution.

"People with asthma have told us that on days when air pollution levels are high they feel that they can't even leave the house for fear that it will trigger an attack."

A Met Office spokeswoman said high pressure and very few winds is causing the pollution patch to hang around.