Pollutions are the materials/factors which causes adverse effect on natural quality of any component of the environment.

(A) there are two types of pollutions sources

  • Primary pollutants – they enter the atmosphere directly from versus source.
  • Eg oxides of sulphur nitrogen co etc
  • Secondary pollutants- they are format by chemical reaction between primary pollutant and other atmosphere constituents in the presence of sunlight.
  • The phenomenon of their formats is called synergism they are more ponts and toxin then primary pollutant.
  • Eg Hydrogen + nitrogen sunlight peroxyacetyl nitrate (PAN)

(B) there are two types of pollutant in in nature

  • Biodegradable – These pollutant kos waste products are slowly degraded by microbial action.
  • They are easily manageable by natural process engineered systems sach as waste treatments plant.
  • Non-Biodegradable –
  • They are either non degradable or degrade very slowly by decomposers in tha nature. They often accumulate do not enter biogeochemical cycles.
  • Eg Pesticides,plastic, soft drink cans, polyetylene bags,chlorinated hydrocarbons.

Kinds of Pollution

(A) Based on path of environment affected

  • Air pollution
  • Water pollution
  • Soil pollution

(B) best on origin of pollution

  • Natural—Volcanic eruption,forest fire,release of methane by paddy fild and alimentary canal of cattles.
  • Anthropogenic/Men made pollution– -Industrial, agricultural pollutions.

(C) Basel on physical natural of pollutants

  • Gaseous pollution
  • Thermal pollution
  • Noise pollution
  • Radioactive pollution

Air pollution

(A) best of organ of pollution pollutants are

  • Natural— originate by natural process
  • Example — Pollen dust, smoke (forest fire volcanic ash)etc.
  • Anthropogenic — originate bye man made  pollution either have fixed source. example — industries, mineral power plants etc

(B) based on nature of pollution pollutants are

  • Primary air pollutants — there exits age particulate matter of gaseous forms.
  • Particulate matter — these are tiny solid Particles/ liquid droplets that remains suspend in air. They cause respiratory disorders and alter atmospheric temperature.
  • Eg Soot, smoke dust, metal dust, pollene etc.
  • Gaseous forms — CO —
  • It is poisonous gas having 200 times more affinity for HB then oxygen.
  • It is causes headache and giddiness.


Hydrocarbon/ volatile organic carbon

  • They are produced naturally by certain types of plants decomposition of organic matter burning of fossil fuel
  • and also by flooded rice field and swamps.
  • some of the hydrocarbons are carcinogenic

Eg Bengene, formaldehyde etc.


Burning of coal, oil refineries, ore smelters/ putrefaction produces SO2. It cause respiratory disorders and are harmful to plants. Epiphytes are the indicators of high SO2

Eg. Paramelia, usnea, cladonia and garden pea etc.

Nitrogen oxide

  • It is produced by combustion of fossil fuel in automobiles.
  • it it contributes to acid rain that causes skin disorders enhaces heart and lung problems.


They are used as refregerants, propellents, solid plastic emitted during flying jet, it along with NOx react with ozone and deplete

the ozone layer which lead to the increase in UV radioactive on earth.


It is an effective oxidant that errodes building surface and causes lung cancer.


  • It damage chloroplast so reduces photosynthetic efficiency and growth of plant.
  • it causes irritation of eyes and inhabits ET chain.


Damage kidneys, liver, spleen and lung.


It causes irritation in gastrointestinal and respiratory tract.

Acid rain

It is the presence of acid in rain water normal rain water H2O+CO2 is a weak acid of PH-6.5 but acid rain has TH 5.6 to 4.

Nitrogen oxide hydrocarbons formed during combustion of coal and petroleum are highly reactive in air and produces acid.

Wet deposition

Acidic water received through rain, foh, snow, dew, mist etc.

Dry deposition

Deposition of wind blow acidic gases and particles on the ground.