Airborne particles cause more than 3m early deaths a year

GOVERNMENTS fret over traffic and other local nuisances that create filthy air. But research just published in Nature by Zhang Qiang, of Tsinghua University in Beijing, and an international team including environmental economists, physicists and disease experts, suggests the problem has a global dimension, too. Dr Zhang’s analysis estimates that in 2007—the first year for which complete industrial, epidemiological and trade data were available when the team started work—more than 3m premature deaths around the world were caused by emissions of fine particulate matter (known as PM2.5, because the particles in question are less than 2.5 microns across).