The European Court of Justice (ECJ) on Wednesday ruled in favor of citizens and environmental groups in a case about air pollution standards.

Residents of the Belgian capital, Brussels, and an environmental group had sued local authorities over their air quality scheme. A court in Brussels had referred the case to the ECJ to decide how stringently EU law should apply to air quality measurements in the Brussels region.

Read more: German cities get more funding for air quality, but retro-fitting plan still to come

What was the main concern?

- Should national courts be allowed to review the stationing of air quality sampling points?

- Can results from different sampling stations, which measure toxic substances in air, be averaged to determine a broader region's compliance with air quality standards?

Read more: Air pollution linked to half million premature deaths in Europe

ECJ ruling

ECJ judges in Luxembourg ruled Wednesday that sampling stations should be set up in areas with the highest pollution levels, in accordance with EU law.

"The location of sampling points is central to the air quality assessment and improvement system, in particular where the pollution level exceeds a certain threshold," the judges wrote, adding that while local authorities decide on the sampling sites, national courts can review those decisions, including in cases brought by residents.

The ECJ also ruled that air quality compliance should not be based on the area average but the results from individual sampling stations, meaning that if one particular station shows excessively high levels of a toxic substance, it will be deemed a violation of EU air quality standards irrespective of the better air quality in the surrounding area.

Read more: Bonn, Cologne ordered to ban older diesel vehicles

Europe still lagging on air quality Problems across the bloc Eight European Union countries exceeded the bloc's air pollution limits in 2011, down from 12 the previous year, the European Environment Agency said in a report published on Monday. Austria, Belgium, Finland, France, Germany, Ireland, Luxembourg and Spain remained above limits, while Denmark, Malta, the Netherlands and Sweden managed to bring their air pollution below the authorized levels.

Europe still lagging on air quality Powerplants, factories and cars The most serious air pollutant in Europe is called "particulate matter," including soot, nitrogen oxides and ozone. Particulates, smaller than 2.5 micrometers, can penetrate deep into the human lungs. The European Environment Agency (EEA) says the burning of fossil fuels in electricity generation, industry and transport generates significant amounts of particulates.

Europe still lagging on air quality Transport the main problem Cars and trucks make up 40 percent of all nitrogen oxides emitted in the European Union. EEA Executive Director Jacqueline McGlade also said the emissions in some European cities urgently need to be looked at. Paris, Marseille, Turin, Milan, Rome and a number of Czech, Polish and Bulgarian cities have the highest levels of particle pollution.

Europe still lagging on air quality A danger to our lungs Particulate matter is a combination of fine solids and aerosols that are suspended in the air. Increases in particulate pollution have been linked to respiratory and cardiovascular illness, heart attacks and slowed lung development in children and teenagers.

Europe still lagging on air quality New transport solutions Denmark, Malta, Sweden and the Netherlands managed to bring their air pollution levels below the legal limits. In Amsterdam, city officials reduced the number of large vehicles allowed in the city center, built speed bumps, implemented speed limits and improved public transit. Residents were also encouraged to use bikes, reducing the number of cars on the roads.

Europe still lagging on air quality Danes set an example Denmark saw among the largest improvements in air quality across Europe, according to the report. The Danish Minister for Climate and Energy Martin Lidegaard (left) and the Minister for Environment Ida Auken (right) have worked hard in the last few years to make Denmark's a green and sustainable economy by addressing the country's economic crisis as well as its climate and resource problems.

Europe still lagging on air quality Choking on exhaust German air pollution levels rose in 2011, despite the recent implementation of green zones intended to reduce fine particle emissions from traffic in cities. Cars emitting high levels of pollutants are now banned from entering major urban areas. The disappointing result may have been caused by weather systems that trapped a layer of cold air over the country and kept pollutants from escaping.

Europe still lagging on air quality One small solution Although major improvements in air quality in the atmosphere are best achieved through long-term infrastructure changes, there is an easy way to improve the air quality in your own home. Many indoor plants, like the Spathiphyllum (more commonly known as the lily), are good at reducing contaminants in the air. Author: Saroja Coelho & André Leslie



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