We could live about a month without food. We could even live for several days without water. But without air, we cannot live more than a few minutes.
We might foul the air so badly in some places that it could become unfit to breath. In some areas, the air is so bad that people become sick from breathing it, and some even die because of it.
The World Health Organization estimates that a billion people live in places where the air is substandard and that air pollution kills 8,000 people a day worldwide. About 90% of the deaths occur in developing countries.
