The combined effects from ambient (outdoor) air pollution and indoor (household, in particular) air pollution cause approximately 7 million premature deaths every year, largely as a result of increased mortality from stroke, IHD, COPD, lung cancer and acute respiratory infections (1). Air pollution can occur in both the outdoor and indoor environments. Cook-stoves in homes, motor vehicles, industrial facilities and forest fires are common sources of air pollution. Air pollutants with the strongest evidence for adverse health outcomes include particulate matter (PM; both PM 2.5 (i.e. particles with an aerodynamic diameter equal to or less than 2.5 μm) and PM10 (i.e. particles with an aerodynamic diameter equal to or less than 10 μm), ozone (O 3), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ) and carbon monoxide (CO). Air pollution is however composed of many more pollutants (1).