Air pollution is an important public health problem in
most cities of the developing world. Pollution levels in
megacities such as Bangkok, Cairo, Delhi and Mexico
City exceed those in any city in the industrialized countries.
Epidemiological studies show that air pollution in
developing countries accounts for tens of thousands of
excess deaths and billions of dollars in medical costs
and lost productivity every year. These losses, and the
associated degradation in quality of life, impose a significant
burden on people in all sectors of society, but especially
the poor.