Fill in the Blanks Exercise 10. Complete the text (Pollution)Online version Complete this text. by Teacher Diana Liz Villalbante 1 environment pollutants human materials trash Pollution factories damage volcanic harmful runoff is the introduction of materials into the . These harmful are called . Pollutants can be natural , such as ash . They can also be created by activity , such as or produced by . Pollutants the quality of air , water , and land .