In Asia - with half of the world's city dwellers - more than 500,000 people die every year from diseases related to Urban Air Pollution
Upto two-thirds of the approximately 800,000 deaths and 4.6 million lost life-years due to urban air pollution across the globe annually occur in the developing countries of Asia, says the World Health Organisation (WHO).
WHO estimates that 1.5 billion urban dwellers face levels of outdoor air pollution that are above the maximum recommended limits.
About half a million deaths each year globally can be attributed to particulate matter and sulphur dioxide in outdoor air. Bringing suspended particulate matter down to safe levels could save between 300 000 and 700 000 lives annually, said WHO.
According to the HEI report, combustion is mainly responsible for the pollutants being emitted. In poorer cities, the burning of refuse (garbage and biomass) contributes considerably to air pollution. (See the Do u Know on Ewaste ) Although centralised refuse burning on a large scale is largely responsible, small-scale burning also has a large impact in most Asian cities.
In most cities, the main source of combustion is fuel use, which tends to increase along with population size and economic activity. Although emissions vary according to combustion conditions and emission-control technology, fuel type is a useful indicator of potential emissions; coal and biomass are high-emitting fuels while liquefied petroleum gas is a low-emitting fuel.
According to the HEI report, air pollution in Asian cities is closely linked to levels and trends in economic and social development. In addition to rapid industrialisation, urbanisation, population growth and demand for transportation, meteorological conditions too influence air pollution levels in most South Asian and South-East Asian cities.
Projections suggest that Asia, owing to its expected economic growth, may experience substantial increases in its use of coal and motor vehicle fuels.
In addition to outdoor urban air pollution, indoor pollution is also a serious source of concern in the developing countries of Asia where 60-80% of households rely on solid biomass fuel for cooking and heating. These fuels are usually burnt in low-efficiency, unvented traditional devices and result in high levels of indoor air pollution. Women and children face maximum exposure because they spend most of their time indoors, working with or near combustion sources. Around 30-60% of urban residents in low-income countries reportedly live in poor households and are exposed to high levels of indoor air pollution.
Quoting recent studies, the HEI report says the effects of indoor air pollution include acute lower respiratory infections in children below five years, chronic obstructive pulmonary disease and lung cancer.