What is Air Pollution? It gets dirty in the air. This is a big problem in some parts of the world. What causes air pollution? Humans cause it by burning fuel in buses, cars, factories, houses, schools and trains. Smoke from burning fuel contains toxic gases and dust. They get into the air and make it dirty. Why is pollution bad? Dirty air hurts people. It helps to relieve colds, coughs and diseases of the heart and lungs. It also injures plants and animals and soils clothing and buildings. 1. What is the dust in the air called? .............................................. ....................................................... ............. 2. How do humans cause air pollution? ................................. ....................................................... ................................................................. ............. 3. Does dirty air hurt people? ................................................. ................................................. . 4. Is pollution so bad? .......................................................... .............................. ............