Microscopic particles, among the most harmful forms of air pollution, are still found at dangerous levels in Europe, a European Environmental Agency (EEA) report said. On average, air pollution is cutting human lives by roughly eight months and by about two years in the worst affected regions, such as industrial parts of Eastern Europe. Particulate matter is the most serious air pollution risk in Europe. Using the most recent data, from 2010, the report said 21 percent of the urban population was exposed to larger particulate matter at concentrations above a daily EU limit. Up to 30 percent of city-dwellers faced exposure above a yearly EU target level to finer particles, small enough to pass from the lungs into the bloodstream, making them particularly hazardous to health. World Health Organization (WHO) levels are more rigorous than those set by EU law. By the WHO standards, almost all the European urban population was exposed to dangerous pollution. Another of the major air pollutants is ozone, which can cause respiratory problems. Again exposure levels were high, with sunny Mediterranean nations particularly affected, as sunlight is needed to form ozone. In 2010, 97 percent of EU inhabitants suffered ozone above the WHO reference levels in 2010 – and 17 percent above the much lower EU target level. The pollutants result from fumes belched out by cars, industry, household fuel burning, followed by complex chemical reactions in the air. The report highlights the legislative need to tackle air pollution and human health in tandem with the struggle to slow global warming. While many pollutants are an unremitting problem, the report says there has been success in dealing with sulphur dioxide, whose levels have dropped following laws on sulphur content in fuels. In 2010, the EU urban population for the first time was not exposed to sulphur dioxide above the EU limit level.