1 active motor vehicles. The car is causing a problem, the most polluted air.
2. poisonous gas and smoke from factories
3. Birthplace: dust on the construction furnaces at coal-fired commercial
funeral pyre cremation
4. Source of accumulation of sewage and solid waste, including food scraps
5. Smoke from a burning cigarette from burning forests and farm
6. Experimental nuclear weapons pose radioactive aerosol
7. Detection and treatment of Radiology using radio isotopes that are missing the correct measures in. Climate protection, waste
8. Bad air caused by natural phenomenon such as a volcano explosion earthquake wildfire