"Air pollution is currently the most important environmental risk to human health," the report says.
According to Air Quality standards expert Alberto González Ortiz, the level of hazardous particles has been reducing in European cities but not fast enough.
"We have not yet reached the EU standards and of course we are far from reaching the WHO (World Health Organization) standards," Ortiz said.
It is noted that the EU legislation now demands from the countries to evaluate the level of ambient contaminants, including ozone and particulate matters, and take measures if certain limits are hit.
EU limits are set per pollutant and in 2017, 16 out of the EU’s 28 member states reported at least one case of levels of nitrogen dioxide, a poisonous gas in car exhaust, is higher than the legal EU annual mean concentration. This list includes France, Belgium, the Netherlands, Spain, Germany, and UK.