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Lesson 19

Air Pollution

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       Air pollution occurs when the concentrations of certain substances become high enough to cause the atmospheric environment to become toxic. Air pollutants can be gaseous, liquid or solid in form, and can come from natural as well as human sources. Examples of natural sources of air pollution include forest fires, pollen, volcanic emissions, and dust. Human sources of air pollutants include emissions from industry, agriculture, forestry, transportation, power generation, and space heating.

Air pollution can threaten the health of human beings, trees, lakes, crops, and animals. Abundant amounts of air pollution changes natural atmospheric processes, causing acid rains, ozone hole, and enhancing greenhouse effect. Additionally, it causes economic losses.

Pollutants are classified either as primary pollutants, or those that enter the atmosphere directly from various sources, or as secondary pollutants, or those that are formed when primary pollutants react with each other or with other compounds present in the atmosphere.

Industrial or gray smog is considered the most serious type of air pollution. Smoke and oxides of that are released by burning coal and oil containing minor amounts of sulfur is the cause. The smoke gives the air a gray color. Industrial smog has been known to cause air pollution disasters. One of the worst occurred in London in December of 1952. Five days of stagnant air brought about high-pressure systems caused between 3,500 and 4,000 deaths.

Another main cause of air pollution is exhaust fumes from cars and other vehicles that run on gasoline or diesel. Until a few years ago, lead was added to most gasolines to make car engines run better. The lead passes through the engine and out of the exhaust system into the air. Lead is a highly toxic metal and can cause nervous system damage and digestive problems.

Road traffic emissions, particularly from diesel vehicles are a major source of particulate matters and nitrogen oxides. PM10 particles (the fraction of particulate in air of very small size (<10 µm)) are of major current concern, as they are small enough to penetrate deep into the lungs and so potentially pose significant health risks. Particles are often classed as either primary or secondary pollutants.

Sulfur and nitrogen oxides (primary pollutants) from power plants, industry, cars and other sources cause rain, snow and fog to become acidic. The most serious damage caused by acid rain today is acidification of water lakes and rivers. In some cases they become so acidic that they can no longer support fish and their food chains. Forest health can also be affected from this in areas where the soils are being acidified.

Ozone depletion is another result of pollution. The ozone layer in the stratosphere protects the earth from harmful ultraviolet radiation from the sun. Release of chlorofluorocarbons (CFC's) from aerosol sprays, polystyrene containers, refrigerator coolant and air conditioning units removes some of the ozone, causing "holes"; to open up in this layer and allowing the radiation to reach the earth.

Ozone in the in the upper level occurs naturally and protects life on earth but ozone at ground level is a noxious pollutant. It is the major component of photochemical smog (also know as brown smog) and presents the most intractable urban air quality problem. Ozone is not emitted directly. It is secondary pollutant formed in the atmosphere through a complex set of chemical reactions involving hydrocarbons, oxides of nitrogen, and sunlight. The rate at which the reactions proceed is related to both temperature and intensity of the sunlight.

The greenhouse effect, also referred to as global warming, is generally believed to come from the build up of carbon dioxide (CO2) gas in the atmosphere. Carbon dioxide is produced when fuels are burned. Plants convert carbon dioxide back to oxygen, but the release of carbon dioxide from human activities is higher than the world's plants can process. The situation is made worse since many of the earth's forests are being removed, and plant life is being damaged by acid rain.

Finally, air pollution can also occur indoors. Common indoor air pollutants include carbon monoxide and nitrogen dioxide from faulty gas heaters and cookers, carbon monoxide and benzene from cigarette smoke, and volatile organic compounds (VOCs) from synthetic furnishings, vinyl flooring and paints. In addition, there are biological pollutants such as dust mites and mould.

Adequate ventilation is a key to controlling exposure to indoor air pollution. Home and work environments should be monitored for adequate airflow and proper exhaust systems installed.

Air pollution generates various economic losses but their detailed estimation is extremely difficult. They may be divided into four groups: expenses for air quality protection; expenses generated by the worse health condition of the society; losses of raw materials which become air pollution; losses caused by the increased corrosion of machines, buildings, and damage of historical buildings and monuments.

The problem of air pollution is worldwide and transcends national boundaries. Though air pollution is still a serious problem, in many countries in the world, steps are being taken to stop the damage to our environment from air pollution. Many electric power plants, factories, and facilities that burn wastes are equipped with devices called scrubbers. Scrubbers remove sulfur dioxide and other pollutants before the wastes are released into the air. Also, today's cars are designed to create less pollution. Many are equipped with anti-pollution devices called catalytic converters, which reduce the amount of pollution from automobile engines.

Vocabulary
  1. pollution - замърсяване
  2. to occur (-rr-) - 1. срещам се, намирам се (за минерала, растения и пр.); 2. ставам, случвам се, настъпвам (за събитие и пр.)
  3. pollutant - замърсяващо околната среда вещество
  4. gaseous - газов, газообразен
  5. liquid - течен
  6. solid - твърд (не течен); ~ state твърдо състояние;
  7. pollen - бот. цветен прашец
  8. emission - изпускане, изхвърляне, отделяне; излъчване
  9. dust - прах
  10. power generation - производство на енергия
  11. to threaten - заплашвам, застрашавам
  12. acid rain - киселинен дъжд
  13. ozone hole - озонова дупка
  14. to enhance - повишавам, усилвам, увеличавам, покачвам (стойност и пр.)
  15. greenhouse effect - парников ефект
  16. economic losses - икономически загуби
  17. compound - смес; хим. съединение
  18. oxide - хим. окис
  19. to release - изпускам, отделям (газове и пр.)
  20. sulfur (sulphur) - сяра
  21. disaster - бедствие, нещастие; катастрофа
  22. stagnant - застоял
  23. high-pressure - високо налягане
  24. to exhaust - изпускам (пара и пр.)
  25. fume - обик. pl дим, пари; изпарение
  26. vehicle - (сухопътно) превозно средство
  27. gasoline - ам. бензин
  28. lead - олово
  29. digestive - храносмилателен
  30. particulate matter - микроскопична частица вещество, което причинява сериозно замърсяване на въздуха, и чиито източник са предимно пътно-транспортните средства
  31. nitrogen - хим. 1. азот; 2. attr азотен
  32. fraction - частица
  33. to penetrate - прониквам/навлизам в; минавам през; достигам до
  34. to pose - представлявам (проблем, затруднение, заплаха)
  35. particle - частица; капчица; трошица
  36. power plant (US FOR power station) - електроцентрала
  37. acidification - окисляване, окисление
  38. food chain - хранителна верига
  39. depletion - изчерпване; намаляване
  40. ozone layer - озонов слой
  41. harmful - вреден
  42. polystyrene (US USUALLY TRADEMARK Styrofoam) - полистирол - вид пластмаса, която се използва като електроизолационен материал, за производство на лакове и др.
  43. refrigerator - хладилник
  44. air-conditioner - климатична инсталация
  45. unit - тех. елемент, секция; агрегат
  46. noxious - 1. вреден, пагубен (to); 2. нездравословен
  47. intractable - неподатлив; упорит
  48. to emit (-tt-) - издавам, изпускам, отделям; изхвърлям; излъчвам
  49. hydrocarbon - хим. въглеводород
  50. to proceed - извършвам се, ставам, протичам
  51. carbon dioxide (CO2) - въглероден двуокис
  52. fuel - гориво; топливо
  53. plant - растение
  54. oxygen (H2O) - кислород
  55. to process - обработвам, преработвам
  56. indoors adv. - у дома, вътре, вкъщи; на закрито
  57. carbon monoxide (CO) - въглероден окис - безцветен и без миризма отровен газ, който гори със син пламък и образува въглероден двуокис. Основен източник на СО са моторните превозни средства.
  58. faulty - дефектен, повреден, неизправен
  59. benzene - хим. бензол
  60. volatile - хим. летлив, бързо изпаряващ се/изветряващ
  61. furnishings - pl. мебелировка, мебели
  62. vinyl - вид пластмаса, винил - пластичен материал, който може да се огъва и се използва за подови покрития и др.
  63. mite - червейче
  64. mould - плесен
  65. raw - суров, необработен
  66. expenses - разходи
  67. wastes - остатъци, останки; отпадъци; брак
  68. scrubber - устройство за пречистване
  69. sulfur dioxide (SO2) - серен двуокис
 Economic, economical or Economics


Test it out!

Fill the gaps in the sentences, using the words and phrases below:

noxious pollutant; particulate matters; photochemical smog; volatile organic compounds; lead; disasters; gaseous, liquid or solid; oxides of nitrogen; fuels; smog; wastes; air pollution; ozone depletion; sulfur and nitrogen oxides; dust mites and mould; greenhouse effect; acidification; carbon dioxide; indoors; sulfur; exhaust fumes; to penetrate; economic losses

1. occurs when the concentrations of certain substances become high enough to cause the atmospheric environment to become toxic.
2. Air pollutants can be in form, and can come from natural as well as human sources.
3. Abundant amounts of air pollution changes natural atmospheric processes, causing acid rains, ozone hole, and enhancing .
4. Industrial or gray is considered the most serious type of air pollution.
5. Smoke and oxides that are released by burning coal and oil containing minor amounts of is the cause.
6. Industrial smog has been known to cause air pollution .
7. Another main cause of air pollution is from cars and other vehicles that run on gasoline or diesel.
8. Until a few years ago, was added to most gasolines to make car engines run better.
9. Road traffic emissions, particularly from diesel vehicles are a major source of and nitrogen oxides.
10. PM10 particles are of major current concern, as they are small enough deep into the lungs and so potentially pose significant health risks.
11. from power plants, industry, cars and other sources cause rain, snow and fog to become acidic.
12. The most serious damage caused by acid rain today is of water lakes and rivers.
13. is another result of pollution.
14. Ozone in the in the upper level occurs naturally and protects life on earth but ozone at ground level is a .
15. Ozone is the major component of and presents the most intractable urban air quality problem.
16. Ozone is secondary pollutant formed in the atmosphere through a complex set of chemical reactions involving hydrocarbons, , and sunlight.
17. The greenhouse effect, also referred to as global warming, is generally believed to come from the build up of gas in the atmosphere.
18. It is the major component of are burned.
19. Plants convert carbon dioxide back to , but the release of carbon dioxide from human activities is higher than the world's plants can process.
20. Finally, air pollution can also occur .
21. Common indoor air pollutants include carbon monoxide and nitrogen dioxide from faulty gas heaters and cookers, carbon monoxide and benzene from cigarette smoke, and from synthetic furnishings, vinyl flooring and paints.
22. In addition, there are biological pollutants such as .
23. Air pollution generates various but their detailed estimation is extremely difficult.
24. Many electric power plants, factories, and facilities that burn are equipped with devices called scrubbers.


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