400,000 Europeans die prematurely every year from air pollution.
The Czech Republic is one of nine EU states summoned to Brussels recently to explain what they're doing about illegally high pollution levels.
Officials from the nine, including Germany, Spain, France, Italy, Hungary, Romania, Slovakia and the UK, were censured at an air quality ministerial summit on 30 January.
They were warned that if they don't lower their levels they'll be referred to the European Court of Justice - and cases against Bulgaria and Poland have already commenced.
EU air quality limits are currently breached in 130 cities in 23 EU countries and every year, more than 400,000 Europeans die prematurely from air pollution.