Compléter Exercise 10. Complete the text (Pollution)Version en ligne Complete this text. par Teacher Diana Liz Villalbante 1 damage volcanic trash human materials factories pollutants runoff environment harmful Pollution 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 .