The European Commission has referred Spain and Bulgaria to the Court of Justice of the EU for their failure to protect citizens from air pollution.

"We are taking these steps because air pollution is still the biggest environmental health problem in the European Union, responsible for some 400,000 premature deaths each and every year," said EU environment commissioner Karmenu Vella on Thursday (25 July).

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Commissioner Karmenu Vella: 'EU legislation is not bureaucratic. (...) It's about improving people's lives, wherever they are.' (Photo: European Commission)

The court referrals are the final step the commission can take in the so-called infringement procedure, which is the main legal tool the commission has to persuade national governments of EU states to do what they promised.

"We have set a limit to air pollution. When I say we, it is not just the EU, but we've set these air pollution limits with the national governments," said Vella.

Spain has failed to keep the concentration of nitrogen dioxide (NO2) in the air below the EU limits which have been legally binding since 2010.

Bulgaria failed to do so with the level of sulphur dioxide, which were already part of EU law when the eastern country joined the EU in 2007.

Member states' failure to respect air quality levels is one of the most pressing environmental and health issues the EU is facing.

In addition to causing premature deaths, air pollution also contributes to diseases like lung cancer and asthma.

The commission has opened infringement cases against 20 of 28 EU member states relating to air quality standards, which means sending stern letters and requesting new plans.

But the commission is reluctant to take the last step, sending a country to court.

Vella, who came in office in 2014 and is due to leave as commissioner on 31 October, has tried other means to convince governments to take measures to combat air pollution.

In January 2018, he organised a summit in Brussels with environment ministers – or their deputies – from the Czech Republic, Germany, Spain, France, Italy, Hungary, Romania, Slovakia and the United Kingdom.

The idea was that the political gathering would yield better results than the legal route, but it was to no avail.

Four months later, the commission referred France, Germany, Hungary, Italy, Romania and the United Kingdom to court over their poor air quality.

The Czech Republic, Slovakia, and Spain escaped a referral to court. At the time, Vella said that was because these three countries promised air quality improvement "in a reasonable time frame".

For outsiders it is difficult to understand why the commission decides to refer one air-polluting country to court, while still giving others more time for improvement.

"This commission does not take decisions lightly. We weigh the options carefully and we are never happy to go to court,` said Vella.

"But sometimes it is the only way it is what it takes to achieve results."

One reason for the commission's decision to move on Spain could be the recent U-turn in local politics in its capital.

A low-emission zone, aimed at reducing air pollution, was installed by the previous, left-wing mayor, of Madrid.

Her successor, the centre-right Jose Luis Martínez-Almeida, ran on a platform of suspending the low-emission scheme, called Madrid Central.

The council recently imposed a moratorium on fines related to polluting cars entering Madrid Central.

According to the commission statement about the court referral, the "newest air quality data provided by Spain confirms the systematic breach of EU rules on nitrogen dioxide (NO2) values".

In May 2018, the commission published a strategy paper titled 'A Europe that protects: Clean air for all'.

"One year later the evidence of harm from air pollution still continues to grow," said Vella.

"There is no more room for excuses. We need to see decisive action."

He added that air quality can be improved if there is enough political will.

"EU legislation is not bureaucratic. It's not abstract and it's not about what happens here in Brussels. It's about solving real problems. It's about improving people's lives, wherever they are."