A high pressure system persisting over the UK has brought warm and still conditions, resulting in increased ground level ozone.

A number of sites in the UK have exceeded the EU ozone public information threshold of 180µg/m3.

The latest information on these alerts will be issued on the UK Air website.

Some people are more sensitive to ozone than others and may begin to notice an effect on their breathing. People with asthma are not necessarily more sensitive but, if affected, can use their ‘reliever’ inhaler to alleviate symptoms.

If affected, people are urged to take sensible precautions. In particular, avoiding exercise outdoors in the afternoon can reduce individual exposure to ozone.

If the legal threshold for ozone is again breached, further alerts will be issued on our UK Air website.

Forecasts, latest measurements and health advice are available on UK Air and via Defra’s freephone helpline (0800 556677). Updates on current and forecast levels of air pollution can also be found on Twitter @DefraUKAir.