Calculations using a global Earth chemistry model show that about 80 % of the population worldwide is exposed to fine particulate matter concentrations that are higher than the guideline concentration by the World Health Organization (10 µg/m3
) and 35 % to more than 25 µg/m3
(EU Directive). Presently, gaseous and particulate air pollution causes about 3.4 million premature deaths per year. In the coming decades air pollution and related public health impacts are projected to increase particularly rapidly in South and East Asia and in the Middle East.