Environment Pollution – Air Pollutants

Environment Pollution – Air Pollutants


Environment Pollution – Air Pollutants

Environmental Pollution

Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of chemical substances or energy, such as noise, heat or light. Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants.

Primary Pollutants Persist in the form in which they are added to the environment for ex. DDT, Plastic
Secondary Pollutants Formed by interaction among primary pollutants viz. PAN by interaction of NOx & Hydrocarbons
Biodegradable Pollutants Waste products which are degraded by microbial action for ex. Sewage
Non-Biodegradable Pollutants Not decomposed by microbial action for ex. Plastic, Glass, DDT, Radioactive substances
Quantitative Pollutants Occur in nature & become pollutant when their concentration reaches beyond a threshold level for ex. CO2, NOx
Qualitative Pollutants  Do not occur in nature & are man-made for ex. fungicides, herbicides, DDT

Air Pollutants

Major Air Pollutants

  • By incomplete combustion of carbon-based fuels, Automobile exhaust, Cigarette smoke
  • Combines with haemoglobin to form carboxyhaemoglobin, which is highly stable & reduces oxygen carrying capacity of blood
  • Slow our reflexes & make us confused & sleepy
  • Major greenhouse gas formed by respiration, burning of fuels, decomposition of lime, volcanic eruption
  • Released mainly from air conditioning systems & refrigeration
  • Detrimental to Ozone layer present in the stratosphere as CFC + UV >> Cl (Chlorine radicals which causes breakdown of Ozone)
  • Present in petrol, diesel, lead batteries, paints, hair dye products etc. (Affects children in particular)
  • Damages nervous system & cause digestive problems & in some cases causes cancer
  • Formed when NOx particle from vehicle exhaust & volatile Hydrocarbons interact with each other in presence of sunlight
  • SPMs in air, when breathed in causes lung damage & respiratory problems
  • Produced from burning coal (60 %), mainly in thermal power plants + Petroleum products + in production of paper & smelting of metals
  • Major contributor to smog causing lung diseases
  • Mainly CH4 burns in fossil fuels + produced by burning of vegetation / rotting
Acid Rain
  • Ph < 5.6 (Rain with oxides of sulphur & nitrogen (SO2 & NO2)) – HNO3 + H2SO4
  • NO3- Acts as a fertilizer to the soil
  • Automobile exhaust produces NO2 which damages plant leaves & retard rate of photosynthesis + also causes red haze & lung irritation
Classical Smog
  • Occurs in cool humid climate
  • Chemically reducing hence called reducing smog.
  • Smoke + fog + SO2

Ph value is a logarithmic index for hydrogen ion concentration in an aqueous solution, & each increasing Ph value diminish acidic nature of the solution by 1/10th.

Photochemical Smog 
  • Occurs in warm, dry & sunny climate
  • Result from the action of sunlight on unsaturated HC & NOx produced by factories & automobile
  • Chemically oxidising hence called oxidising smog
  • Ozone + Acrolein + Formaldehyde + Peroxyacetyl Nitrate (PAN) are produced which cause serious health problems, severe plant damage, cracking of rubber & corrosion
  • Catalytic Converter – Prevent release of NO & HC to environment
  • CO2, CH4, CFC, N2O, SF6, HFCs, PFCs, CCl4, CH3CCl3,  Water Vapour, O3
  • Mainly from carpets, particle boards & insulation foam  Causes irritation & allergies
  • A gas naturally emitted by soil
  • Due to poor ventilation it is confined inside house & causes lung cancer

Fly Ash

  • Residue produced whenever combustion of solid material takes place, which rises with the gases in atmosphere & causes respiratory problems
  • Contains Aluminium silicates, SiO2 & Calcium oxide (CaO) + Toxic metals like lead, arsenic, cobalt etc.
Advantages of Fly Ash
  • Cement can be replaced by fly ash up to 35 % hence reducing cost of construction
  • Fly ash bricks are lighter in weight & offer high strength & durability
  • A better fill material for road embankments & concrete roads
  • Can be used in reclamation of wasteland, can increase crop yield & enhances water holding capacity of land

Sources of Air Pollutant Emission:  Industry > Transportation > Agriculture

Diseases By Air Pollutants

Yokkaichi asthma (SO2)

  • Burning of petroleum and crude oil releases large quantities of sulfur oxides which causes severe smog
  • Results in severe cases of chronic obstructive pulmonary disease, chronic bronchitis, pulmonary emphysema, and bronchial asthma

Pneumoconiosis / Black Lung Disease

  • an occupational lung disease caused by inhalation of coal dust, often in mines


  • a lung disease, which leads to long-term breathing complications, caused by exposure to asbestos (No cure)


  • a lung disease that is caused by inhaling tiny bits of silica mainly by the workers working in silica industries or sand blasting sites


  • Breaking down of lung tissues due to air pollution & cigarette smoke leading to difficulty in expanding & contracting of lungs
Leave a Reply

Your email address will not be published. Required fields are marked *

Subscribe to our Blog Updates

Instantly receive our best-selling book «10 Productivity Myths» in PDF for Free.

You May Also Like
Aquatic Ecosystems & Eutrophication

Aquatic Ecosystems & Eutrophication

Aquatic Ecosystems & Eutrophication An aquatic ecosystem is an ecosystem in a body of water. Communities of organisms that are dependent on each other and on their environment live in…
View Post
Forest Ecosystem

Forest Ecosystem

Forest Ecosystem Tundra Ice frozen soil with severe climatic conditions Tropical Lying near the tropics or in equatorial region Temperate Between Tropics & Arctic circles i.e. from 23.5* to 66.5*…
View Post
Different types of Species

Different types of Species

Different types of Species  Keystone species Species which determine the ability of a large number of other species to survive. Extinction of keystone species has snowballing effect on extinction of…
View Post