Asthma sufferers get Easter smog warning

Officials at the Department for Environment, Food and Rural Affairs (Defra) said high levels of pollution are expected across England and Wales over the weekend because of warm and still conditions brought on by the high pressure system.

Some people, including those with asthma, could be affected by the high pollution levels and may notice an impact on their breathing.

The public is being advised to take “sensible precautions”, including avoiding taking exercise outside in the afternoon if they are susceptible to the pollutants and not taking unnecessary short car journeys, to help reduce the build-up of ozone.

Defra said elevated levels of PM10s and ozone, reaching high or moderate measures, were expected until at least Sunday, while other pollutants will remain at low levels.

Experts said people suffering from lung diseases, particularly the elderly, should be aware that their breathing could worsen.

Ground level ozone is formed when sunlight acts on nitrogen dioxides and other atmospheric substances which come from a range of sources, including petrol and other fuels. Particulates, or PM10s, also come from vehicles.

The smog alert, the first for more than a year, comes as monitoring in London revealed that one site, on the Marylebone Road, has exceeded EU rules for the number of days in the year in which high levels of PM10s are permitted.