Q&A: Everything you need to know about air pollution

As the UK is hit with another wave of air pollution we look at the causes and effects, what you should do and what action is being taken

Stagnant air from continental Europe, which has picked up pollution from industry and agriculture, is being blown over the UK from the south-east. This air combines with pollutants already present in the air from UK sources, such as nitrogen oxides and particulates from diesel vehicle engines, to produce air pollution.