In order to address significant and persistent exceedances of limit values for two key pollutants with health impacts: nitrogen dioxide and particulate matter, the Commission has taken enforcement action against several EU Member states for failing to respect air quality limit values set out in the Directive 2008/50/EC on ambient air quality and cleaner air for Europe.

Nitrogen dioxide is mostly a result of road traffic and industry. To date, there are 13 infringement cases pending against Member States: Austria, Belgium, the Czech Republic, Germany, Denmark, France, Spain, Hungary, Italy, Luxembourg, Poland, Portugal, and the United Kingdom. Particulate matter is mainly present in emissions from industry, domestic  heating, traffic and agriculture. To date, there are 16 infringement cases pending against Member States: Belgium, Bulgaria, the Czech Republic,  Germany, Greece, Spain, France, Hungary, Italy, Latvia, Portugal, Poland,  Romania, Sweden, Slovakia, and Slovenia. It is worth mentioning that Bulgaria  and Poland were found in breach of EU legislation by the European Court of Justice, in 2017 and 2018, respectively.

In January 2018, at the Air Quality Ministerial Summit convened by Karmenu Vella, Commissioner for Environment, EU member states were called for adoption of credible, effective and timely measures to reduce pollution, as required under EU law. In May 2018, the European Commission stepped up enforcement of the EU clean air legislation and referred France, Germany, Hungary, Italy, Romania, and the United Kingdom to the Court of Justice of the EU for failing to respect agreed air quality limit values and take appropriate  measures to keep exceedance periods as short as possible. In particular, France, Germany, and the United Kingdom are referred to the Court over persistently high levels of particulate matter (PM10), France,Germany, and the United Kingdom are referred to the Court for failure to respect limit values for nitrogen dioxide (NO2), and for failing to take appropriate  measures to keep exceedance periods as short as possible.

Commissioner for Environment, Karmenu Vella said: “The decision to refer  Member States to the Court of Justice of the EU has been taken on behalf of Europeans. We have said that this Commission is one that protects. Our decision follows through on that claim. The Member States referred to the Court today have received sufficient 'last chances' over the last decade to  improve the situation. It is my conviction that today's decision will lead to improvements for citizens on a much quicker timescale. But legal action alone  will not solve the problem. That is why we are outlining the practical help that the Commission can provide to the national authorities' efforts to  promote cleaner air for European cities and towns."