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POLLUTION: CAUSES AND CONSEQUENCES PowerPoint Presentation
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POLLUTION: CAUSES AND CONSEQUENCES

POLLUTION: CAUSES AND CONSEQUENCES

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POLLUTION: CAUSES AND CONSEQUENCES

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  1. POLLUTION: CAUSES AND CONSEQUENCES

  2. What is pollution? • Pollution is the introduction of harmful substances or products into the environment • We will be examining 4 main parts of pollution • Water Pollution • Air Pollution • Soil Pollution • Noise Pollution

  3. Water Pollution

  4. Water Pollution Any chemical, biological and physical change in water quality that has a harmful effect on living organisms or makes it unusable for agriculture • The massive quantity of pollutants produced by more than 7 billion humans, their machines, plants, animals • The limited supply of fresh liquid water into which most water-destined pollutants are discharged • The growing number of ‘technological pollutants’ released into the environment, i.e. manufactured synthetic materials

  5. Causes of Water Pollution • Factors that contribute to water pollution can be categorized into two different groups • Point sources • Non-point sources • Point sources are the easiest to identify and control • Non point sources are ambiguously defined and harder to control

  6. Point Sources • Some point sources of water pollution include • Waste products from factories • Waste from sewage system • Waste from power plants • Waste from underground coalmines • Waste from oil wells • They are called point sources because they are direct sources of water pollution and can be reduced and monitored

  7. Example of a point source

  8. Non-point Sources • The term non-point source encompasses a large range of sources such as: • when rain or snow moves through the ground and picks up pollutants as it moves towards a major body of water • the runoff of fertilizers from farm animals and crop land • air pollutants getting washed or deposited to earth • storm water drainage from lawns, parking lots, and streets

  9. Non-point source: Agricultural runoff

  10. Types of Pollution • Disease-causing Agents – pathogens • Oxygen Demanding Agents – organic waste: manure • Water-soluble Inorganic Chemicals – acids, toxic metal salts. • Inorganic Plant Nutrients – nitrogen and phosphorus • Organic Chemicals – oil, pesticides, detergents • Sediment or Suspended Material – erosion, soil • Water-soluble Radioactive Isotopes – radon uranium • Heat – electric and nuclear power plants

  11. E. coli outbreak in Pune • In May 2000 the small community of pune was laid waste by a toxic strain of E. coli:0157. • The contamination came from the public water supply. • Six people died in the first week • Fouty new cases surfaced in late July, all very young children. • Over a thousand innocent people were infected.

  12. Waterborne Bacteria • Disease symptoms usually are explosive emissions from either end of the digestive tract Escherichia coli Vibrio sp. Barbara E. Moore, Ph.D., Department of Biology, University of Texas at San Antonio

  13. Types and Sources of Pollution • Disease-causing Agents - Pathogens • Oxygen Demanding Agents • Water-soluble Inorganic Chemicals • Inorganic Plant Nutrients • Organic Chemicals • Sediment or Suspended Material • Water-soluble Radioactive Isotopes • Heat

  14. Biological Oxygen Demand (BOD) • BOD: Oxygen is removed from water when organic matter is consumed by bacteria. • Low oxygen conditions may kill fish and other organisms. Sources of organic matter • Natural inputs-- bogs, swamps, leaf fall, and vegetation aligning waterways. • Human inputs-- pulp and paper mills, meat-packing plants, food processing industries, and wastewater treatment plants. • Nonpoint inputs-- runoff from urban areas, agricultural areas, and feedlots.

  15. Types and Sources of Pollution • Disease-causing Agents - Pathogens • Oxygen Demanding Agents • Water-soluble Inorganic Chemicals • Inorganic Plant Nutrients • Organic Chemicals • Sediment or Suspended Material • Water-soluble Radioactive Isotopes • Heat

  16. Heavy Metals • Metallic elements having a density greater than 5 g/cm3 • Most are extremely toxic • Water soluble • Readily absorbed into plant or animal tissue • Bioconcentrate • Combine with biomolecules • Proteins • Nucleic acids

  17. Sources of Heavy Metals • Natural • Redistributed by geologic and biologic cycles • Industrial • Burning of fossil fuels • Environmental pollution

  18. Types and Sources of Pollution • Disease-causing Agents - Pathogens • Oxygen Demanding Agents • Water-soluble Inorganic Chemicals • Inorganic Plant Nutrients • Organic Chemicals • Sediment or Suspended Material • Water-soluble Radioactive Isotopes • Heat

  19. Phosphorus and nitrogen are the major concerns • Sources: • Human, animal (e.g., Hog Farms), and industrial waste • Storm water • Soil erosion • Excessive use of fertilizers for crops, lawns, and home gardens

  20. Types and Sources of Pollution • Disease-causing Agents - Pathogens • Oxygen Demanding Agents • Water-soluble Inorganic Chemicals • Inorganic Plant Nutrients • Organic Chemicals • Sediment or Suspended Material • Water-soluble Radioactive Isotopes

  21. Concentrations increase at increasing levels in the food chain PCBs (Poly chlorinated biphenyl), DDT (DichloroDiphenylTrichloroethane), etc. • Degradable: That can be chemically decomposed: decomposable plastic wastes • Photodegradable: that the product is decomposed (broken down) by exposure to light • Biodegradable: Capable of being decomposed by biological agents, especially bacteria: a biodegradable detergent

  22. Types and Sources of Pollution • Disease-causing Agents - Pathogens • Oxygen Demanding Agents • Water-soluble Inorganic Chemicals • Inorganic Plant Nutrients • Organic Chemicals • Water-soluble Radioactive Isotopes • heat

  23. China Syndrome • In a complete reactor meltdown, the extremely hot (about 2700º Celsius) molten uranium fuel rods would melt through the bottom of the reactor and actually sink about 50 feet into the earth beneath the power plant • Molten uranium would react with groundwater, producing large explosions of radioactive steam and debris that would affect nearby towns and population centers

  24. William Lawless • At Savannah River, South Carolina, the US Department of Energy ran plutonium production reactors (to make plutonium for bombs) and a reprocessing plant (to separate plutonium from spent nuclear fuel) • William Lawless was surprised when he was put in charge of radioactive waste management at the huge military complex

  25. Whistleblower • Lawless wanted to do a good job, so he started asking some pointed questions: • Why were liquid radioactive wastes being poured into shallow trenches, where they could leak into the soil and enter the surface waters? • Why were solid plutonium-contaminated wastes being buried in cardboard boxes and covered with earth? • He was told to keep quiet • Instead, he went public, and promptly lost his job

  26. Post Whistle-Blowing • He was hired to teach mathematics at a local college, which enabled him to make a living while he kept on talking -- to the press, on national radio and TV -- about shoddy waste management practices at Savannah River • Since then, all plutonium production reactors and reprocessing plants have been shut down not only at Savannah River but throughout the US, and environmental cleanup has become a priority

  27. Types and Sources of Pollution • Disease-causing Agents - Pathogens • Oxygen Demanding Agents • Water-soluble Inorganic Chemicals • Inorganic Plant Nutrients • Organic Chemicals • Sediment or Suspended Material • Water-soluble Radioactive Isotopes • Heat

  28. Industrial Water Pollution • Thermal Pollution occurs when water is withdrawn, used for cooling purposes, and then heated water is returned to its original source • An increase in temperature, even a few degrees, may significantly alter some aquatic ecosystems

  29. Air Pollution

  30. Causes of Air Pollution • One of the main causes of air pollution is the release of carbon dioxide into the atmosphere, this happens because of Deforestation and fossil fuel burning • Sulfur dioxide is another air polluter and is released into the atmosphere by the burning of sulfur containing compounds of fossil fuels. Sulfur oxides are very dangerous to humans at a high concentration. Sulfur in the atmosphere is responsible for acid rain

  31. More causes of air pollution: CFCs • Chlorofluorocarbons (CFCs) also contribute to air pollution by reducing the amount of ozone the stratosphere. CFCs come from a variety of places such as: • the burning of plastic foam items • leaking refrigerator equipment • spray cans

  32. Natural Air Pollutants • Natural air pollutants can include: • Smoke from wild fires • Methane released from live stock • Volcanic eruptions

  33. Consequences of Air Pollution • CO2 is a good transmitter of sunlight, but it also partially restricts infrared radiation going back from the earth into space, which produces the so-called greenhouse effect that prevents a drastic cooling of the Earth during the night • Increasing the amount of CO2 in the atmosphere reinforces this effect and is expected to result in a warming of the Earth's surface • CO2 in atmosphereGLOBAL WARMING

  34. The Greenhouse Effect

  35. Acid Rain • When emissions of sulfur dioxide and nitric oxide from stationary sources are transported long distances by winds, they form secondary pollutants such as nitrogen dioxide, nitric acid vapor, and droplets containing solutions of sulfuric acid, sulfate, and nitrate salts • These chemicals descend to the earth's surface in wet form as rain or snow and in dry form as a gases fog, dew, or solid particles, it is known as acid rain or acid deposition

  36. Acid Rain: Its effect on a tree

  37. Smog • With the introduction of petroleum to replace coal economies in countries, photochemical smog has become predominant in many cities, which are located in sunny, warm, and dry climates with many motor vehicles. • Worst episodes of photochemical smog tends to occur in summer.

  38. Consequences continued • Sulfur dioxide, nitrogen oxides, ozone and peroxyacl nitrates (PANs), cause direct damage to leaves of crop plants and trees when they enter leaf pores (stomates) • Chronic exposure of leaves and needles to air pollutants can also break down the waxy coating that helps prevent excessive water loss and damage from diseases, pests, drought and frost

  39. Soil pollution Soil pollution is defined as a phenomenon characterized by the loss of structural and biological properties by the soil layers as a result of numerous human and natural factors, such as wind, deforestation, chemical use, among others, etc.

  40. Causes of soil pollution • Soil can become contaminated in many ways. Chemicals, like herbicides and pesticides, are major polluters; oil dumps, landfills, and industrial wastes can also wreak havoc.

  41. Effects of soil pollution • Causes cancers including leukaemia • Mercury can increase the risk of kidney damage; cyclodienes can lead to liver toxicity • Causes neuromuscular blockage as well as depression of the central nervous system • Also causes headaches, nausea, fatigue, eye irritation and skin rash • Contact with contaminated soil may be direct (from using parks, schools etc) or indirect (by inhaling soil contaminants which have vaporized)

  42. Preventions of soil pollution • Reducing use of chemicals. • Reforestation and recycling of wastes. • Weed control.

  43. Noise Pollution

  44. WHAT IS NOISE POLLUTION? • Sound that is unwanted or disrupts one’s quality of life is called as noise. When there is lot of noise in the environment, it is termed as noise pollution. • Sound becomes undesirable when it disturbs the normal activities such as working, sleeping, and during conversations. • It is an underrated environmental problem because of the fact that we can’t see, smell, or taste it. • World Health Organization stated that “Noise must be recognized as a major threat to human well-being”

  45. Sources of Noise Pollution • Transportation systems are the main source of noise pollution in urban areas. • Construction of buildings, highways, and streets cause a lot of noise, due to the usage of air compressors, bulldozers, loaders, dump trucks, and pavement breakers. • Industrial noise also adds to the already unfavorable state of noise pollution. • Loud speakers, plumbing, boilers, generators, air conditioners, fans, and vacuum cleaners add to the existing noise pollution.

  46. Health Effects • Noise pollution can damage physiological and psychological health. • High blood pressure, stress related illness, sleep disruption, hearing loss, and productivity loss are the problems related to noise pollution. • It can also cause memory loss, severe depression, and panic attacks.

  47. Solutions for Noise Pollution Planting bushes and trees in and around sound generating sources is an effective solution for noise pollution. Regular servicing and tuning of automobiles can effectively reduce the noise pollution. Buildings can be designed with suitable noise absorbing material for the walls, windows, and ceilings. Workers should be provided with equipments such as ear plugs and earmuffs for hearing protection.

  48. Solutions for Noise Pollution Similar to automobiles, lubrication of the machinery and servicing should be done to minimize noise generation. Soundproof doors and windows can be installed to block unwanted noise from outside. Regulations should be imposed to restrict the usage of play loudspeakers in crowded areas and public places. Factories and industries should be located far from the residential areas.

  49. Solutions for Noise Pollution Community development or urban management should be done with long-term planning, along with an aim to reduce noise pollution. Social awareness programs should be taken up to educate the public about the causes and effects of noise pollution.

  50. WAYS TO STOP POLLUTION • You can help to reduce global air pollution and climate change by: • Driving a car that gets at least 35 mpg • Walking, biking, and using public transportation • Using CFL bulbs over incandescent bulbs • Buying only energy efficient appliances • Recycling newspaper, aluminum, and others • Planting trees! • Avoid purchasing products that contain CFCs • Supporting much stricter clean air laws and enforcement of international treaties to reduce ozone depletion and slow global warming