Health Effects of Air PollutionThe health consequences of exposure to dirty air are considerable. On a global basis, estimates of mortality due to outdoor air pollution run from around 200,000 to 570,000, representing about 0.4 to 1.1 percent of total annual deaths (246) (247). As the range of these estimates indicates, it is difficult to quantify the toll of outdoor air pollution. The health impacts of urban air pollution seem likely to be greater in some of the rapidly developing countries where pollution levels are higher. The World Bank has estimated that exposure to particulate levels exceeding the WHO health standard accounts for roughly 2 to 5 percent of all deaths in urban areas in the developing world (248).
As dangerous as polluted outdoor air can be to health, indoor air pollution actually poses a greater health risk on a global level. Indoor air pollution is a concern in developed countries, where, for example, energy efficiency improvements sometimes make houses relatively airtight, reducing ventilation and raising indoor pollutant levels. In such circumstances, even small pollution sources -- emanating from a furnace, a new carpet, or from naturally occurring radon gas -- can lead to significant human exposures. http://www.wri.org/wr-98-99/airpoll.htm |
