In Progress Lesson 1 of 0 In Progress Pollution What is pollution ? Pollution is any harmful addition to the environment Man made examples:LitterDumpingSewage disposalNoiseRadioactivity Natural examples:VolcanoesSmoke from fires What are pollutants ? Pollutants are substances that cause harm to the environment Examples:Carbon dioxide Sulfur dioxideSmoke particlesFertilizer The effects of pollution If too much fertilizer is spread on grassland, the fertilizer may get washed into streams, rivers and lakesThe minerals in the fertilizer cause algae to grow in the waterWhen the algae die they are decomposed by bacteria . This uses up oxygenAll the oxygen in the water gets used up so that all living things die.This process is called eutrification Controlling pollution Limit the use of fertilizerAnimal waste (slurry) should be spread on grassland only when grass is actively growing in spring and when the weather is dry