Environmental Pollution, Water Pollution, Types of Pollution, Types of Water Pollution

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Environmental Pollution

Destabilization of the balance of the atmospheric composition.


It is an unstable change in the composition of the environment due to its physical, chemical and biological changes, which is harmful for human life and other animals living on the earth.

Types of Pollution

  • Air pollution
  • Water pollution
  • Land pollution
  • Noise pollution
  • Industrial pollution
  • Commercial or domestic sector pollution
  • Chemical pollution
  • Radioactive pollution (contamination)
  • Causes of Pollution the ultimate cause of pollution is human activity itself. Pollution is a human contribution to nature. Science has evolved technologies and technologies have helped the human welfare. In the process, the pollution has been a part of technology and therefore a part of human miseries.

Human Activities Mainly Include

  • Industries for various human needs - directly and indirectly
  • Agriculture for food production and industrial needs
  • Health care for health of human beings and animals
  • Transport for mobility of human beings
  • Dwelling for settlement in city or villages
  • Energy for various direct human needs and industrial needs.

Pollutants: Pollutants are those substances which alter the natural composition of the atmosphere or destroy it to harmful level.

Types of Pollutants

1. Primary Pollutants Primary pollutants are those substances which are directly produced by a process. These are:

  • Sulphur oxides
  • Nitrogen oxides
  • Carbon monoxide (CO)
  • Carbon dioxide
  • Volatile organic compounds (VOC) , such as hydrocarbon fuel vapours and solvents
  • Particulate matter (PM) , such as smoke and dust.
  • Metal oxides, especially those of lead.
  • Chlorofluorocarbons (CFCs)
  • Ammonia
  • Garbage, sewage and industrial wastes.

2. Secondary Pollutants Secondary pollutants are those pollutants which are not emitted. Rather, they form in the air when primary pollutants react or interact. These are:

  • Ground level ozone ()
  • Nitrogen dioxide
  • Peroxyacetyl nitrate (PAN)

Effects of Pollution

  • Air Pollution: Irritation of eyes, nose, mouth and throat, Increased respiratory disease, Cancer, Reduced lung functioning, premature death. Acid rain, Ozone,
  • Water Pollution: Waterborne diseases such as; Typhoid, Hepatitis, Diarrhoea, vomiting, and stomach aches, death of aquatic animals, May disrupt photosynthesis in aquatic plants
  • Soil Pollution: Causes cancers including Leukaemia, developmental damage to the brain, kidney damage; depression of the central nervous system, Also causes headaches, nausea, fatigue, eye irritation and skin rash, Contamination of crops, reduce crop yields.

Water Pollution

Definition:- The presence of undesirable substances into fresh and natural water which cause harmful diseases in human beings as well as aquatic life is called water pollution.

Types of Water Pollution

Following are the major types of water pollution.

  • Sea-water Pollution
  • River water Pollution
  • Land Water Pollution

Causes of Water Pollution

Pollution through Domestic Activities: Domestic activities pollute the water when following kinds of wastes are added.

  • Soap and detergents
  • Chemicals used in the houses
  • Waste from slaughter house
  • Waste from hospitals
  • Waste from bakeries
  • Human and animal Faeces
  • Waste food

Pollution through Industrial Activities:

Industrial sector is a great source of pollution of water and air. Many industrial units produce waste materials in the shape of solids, liquids and gases. The industrial wastes are.

  • Poisonous gases
  • Acids, bases and harmful salts
  • Pesticides and plastics
  • Radioactive wastes
  • Toxic wastes from fertilizer factories
  • Wastes from chemical factories

Water Pollution in Pakistan

  • In Pakistan people do not take pain to dispose the waste materials in a proper way. Instead of dumping wastes in the drums and places meant for them they freely throw these into the water drains.
  • Water pollution is very prominent and widespread as a result of urban and industrial activity. Sewage waste from cities and industrial waste are the main factors of water pollution. Many other kinds of wastes which pollute water are from agricultural lands which contain pesticides, waste foods, fertilizers and animal excreta. Wastes from power plants contain radioactive materials, hot water and minerals which also pollute the water.
  • Soaps, detergents, human excreta, animal Faeces, wastes from slaughter houses, disease causing micro-organisms from patients and chemicals etc. are drained into water which causes massive water pollution.

Two Important Industries of Pakistan Causing Water Pollution

  • One of the biggest sources of water pollution is the tanning and leather industry. The industry uses toxic chromium metal and many other toxic substances/chemicals. These toxins are released in natural waters. Effluent of this industry has polluted ground water and water of nearby rivers. This industry is frequent in Kasur and Sialkot area.
  • Pesticide industry in Kala Shah Kaku near Lahore releases huge quantity of acids, pesticides and other dangerous wastes. These wastes are getting entry into a stream flowing nearby. The water of the stream is dangerously polluted. This water ultimately goes to the rivers.


  • Bacteria, viruses, protozoa and worms are carried in polluted water. The diseases caused by them are as under:
    • Bacteria: Typhoid, cholera, Dysentery, enteritis.
    • Viruses: Hepatitis, Polio, Viral enteritis.
    • Protozoa: Amoebic dysentery, diarrhoea.
    • Parasitic worms: Schistostomiasis
  • It causes death of aquatic animals.
  • It decreases the fertility of the soil and results in low production.

Methods to Control Water Pollution

Different methods can be used to control water pollution.

  • The whole sewage waste should be dumped after any treatment. (ii) Sewage treatment plants should be installed in cities.
  • The sewage waste must not be drained in river to save water from pollution.
  • Industrial waste should be treated before reaching natural water.
  • Industries should be established away from cities and rivers.
  • Nuclear dumping in oceans should be banned.
  • Modern scientific methods should be used in agriculture.

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