• domestic sources of pollution are making progress over time while traffic pollution globally is going from bad to worse (10)
• Particulate matters (tiny particles of toxic materials) from vehicle exhaust are very dangerous if breathed in, penetrating deeply into the lungs and bloodstream and potentially damaging the internal organs

While transportation emissions may be a major contributing factor, it is not the only cause of air pollution. Even homes and many types of industries can be linked to air pollution, and these causes must be addressed before real and lasting change can be realized.