Introduction:
Background: Define the large city. (land area, population and density) some examples of disease caused by pollution in such cities like pulmonary disease.
Thesis: This essay aims to discuss three kind of pollution in large cities affect human health. Air, water and land pollution.
Main Body:
Paragraph 1:
TS: The general air pollution such as particulate matter is what large cities cannot avoid neither and can lead to respiratory infection, chornic obstructive pulmonary disease and even blindness.
Air pollution is divided into outdoor air pollution and indoor air pollution.
①Urban air pollutant(natural origin)→tuberculosis, asthma in children
②Indoor environmental tobacco smoke(compared with village homes)
Fail to confirm chemicals in biomass smoke→(lung) cancer
But cooking(may)→lung cancer in women
Paragraph 2:
TS: Recreational waters in large cities also have the risk of causing diseases.
Recreational waters generally contain a mixture of pathogenic and non-pathogenic microorganisms(sewage effluents, livestock, industrial processes, farming activities, domestic animals and wildlife) and free-living pathogenic microorganisms.
→infection of upper respiratory tract, ears, eyes, nasal cavity and skin.
Paragraph 3:
TS: Land pollution contains Solid wastes and Toxic wastes which are the main cause of deadly disease. And this two wastes can also influence the quality of the water. (nutrient enrichment)
Owing to the great growth of economy, the living level of people has risen and the population in large city is enlarged. This also means enormous stress for land using.
People are exposed to relatively large amounts of pesticides, industrial chemicals, and heavy metals, with uncertain health effects.
Conclusion: Air pollution, water pollution and land pollution effect human health though respiratory disease, skin disease and industrial processes.
Reference:
Hester , R.E. and Harrison, R.M. (eds)(1998)