What Are Pollutants?- Definition, Types, and Effects

What is pollutants?

A pollutant is a substance or energy that is introduced into the environment and has undesirable effects or affects the usefulness of a resource. A pollutant can cause long-term or short-term damage by changing the growth rate of plant or animal species or by impairing human convenience, comfort, health, or property values.

Pollutants are the elements, molecules, and particles that are involved in pollution. When exposed to these materials, life can be harmed and their effects on humans and plants are well known. Pollutants can enter the environment naturally and by humans in a variety of ways.

Some pollutants are biodegradable and therefore do not remain in the environment in the long term. However, the breakdown products of some pollutants are themselves harmful to the environment, such as the products DDE and DDD produced from the degradation of DDT.

What pollutants do when they enter the atmosphere, soil, or water supply depends on the type of pollutant. However, it makes sense to characterize them as follows: primary pollutants are released directly into the environment, while secondary pollutants are formed from primary pollutants and external factors.

Many pollutants are introduced into the environment in different ways, have different and sometimes unique health effects, and occur in different amounts. It is difficult to briefly describe these for each chemical, but they can be found on each pollutant’s own page.

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Types of pollutant

Different types of pollutants include:

  • Nitrogen oxides (NOx)
  • Sulfur oxides (SOx)
  • Particulate matter (PM)
  • Ground level ozone (O3)
  • Volatile organic compounds (VOCs)
  • Mercury (Hg)
  • Peroxyacyl nitrates (PANs)
  • and more

1. Stock pollutants

Pollutants for which the environment has a low absorption capacity are called Stock pollutants. Over time, stock pollutants accumulate in the environment. The damage they cause increases as more pollutants are released and persist as the pollutant builds up.

Stock pollutants can put a burden on future generations by circumventing the damage that persists long after the benefits of that damage are forgotten.

2. Fund pollutants

Fund pollutants are those for which the environment has a moderate absorption capacity. Fund pollutants do not cause environmental damage unless the emission rate exceeds the absorption capacity of the receiving environment.

Fund pollutants are not destroyed, but converted into less harmful substances or diluted/dispersed in non-harmful concentrations.

3. Light pollutant

Light pollution is the impact that anthropogenic light has on the visibility of the night sky. It also includes ecological light pollution, which describes the effect of artificial light on individual organisms and on the structure of ecosystems as a whole.

Worst Toxic Pollutants In The World

Let’s Discuss in detail about Different Types of pollutants:

1. Carbon dioxide

Carbon dioxide is one of the trace gases found in the atmosphere it causes air pollutants. It is about 0.04 percent of the atmosphere. Even at this small concentration, it plays an important role in maintaining the Earth’s temperature.

Carbon dioxide is one of the major products when fossil fuels such as coal, natural gas, and oil are burned. It is a major by-product in burning wood and solid waste. Its level in the atmosphere is normally balanced by green plants and trees using the process of photosynthesis.


It is a greenhouse gas. It helps retain the heat and radiation reaching the earth from the sun’s rays, which does not allow heat to escape. Thus, it causes the atmosphere to heat up. This phenomenon is called global warming.

2. Methane

Methane is the natural gas produced in the marshes by anaerobic organisms through fermentation. It is also found underground and below sea level. It is also produced by similar anaerobic organisms in landfills and garbage dumps. 16 percent of methane is produced by cattle and livestock.

Naturally occurring methane is very useful as a fuel for burning and is used daily in our kitchens. It is a greenhouse gas like carbon dioxide and causes the atmosphere to heat up.

3. Plastic

Plastic is a widely used material worldwide. It is made of polymers and is of various types such as polyvinyl chlorides, polyacrylates, phthalates, etc. The pollutant feature of plastic is that it does not biodegrade i.e. it does not break down its individual or simple components.

Larger pieces of plastic only break into smaller pieces, sometimes as small as a microscopic size. They are assumed to last at least 400–1000 years. Before they degrade.

Plastic waste is transported through runoff by air and water, and much of it ends up in oceans and distant places. This leads to the accumulation of drains and, when lit, emits dangerous chlorine gas. As they break into the oceans, they release a compound called bisphenol A which is very toxic to living organisms.

Premature death, birth defects, lower life span, thyroid disturbances, allergic asthma, and cancer are attributed to premature toxins. Plastic wastes contribute to the deaths of many animals and birds, the destruction of fragile ecosystems such as coral reefs, destroying the beauty of natural places.

4. Heavy metals

Heavy metals naturally contain substances, but they are brought into close contact with humans through mining, smelting, fertilizer production, sewage sludge applications, etc.

Metals that are of great concern are arsenic, cadmium, cobalt, chromium, copper, mercury, manganese, nickel, tin, lead, and thallium.

Mercury enters the environment through soil leaching by acid rain, coal burning, industrial, domestic, and mining wastes. In the sea, it accumulates in the body of fish and enters the food chain.

It damages the nervous system and causes a risk to the fetus in pregnant women. There is a debate that mercury found in dental amalgam causes toxicity but this has not yet been proven.

Lead is a component of paints, mining waste, incendiary ash, lead pipe, and automobile exhaust. It damages the brain and nervous system, kidneys, protein synthesis, learning disabilities, and red blood cell formation.

Cadmium Nickel: Cadmium is found in batteries, which emit cigarette smoke and are used in electroplating. It causes kidney disease and affects bone structure.

Arsenic is found in the herb, wood preservatives, and mining industries. It causes skin damage such as hyperkeratosis, pigmentation, and skin and lung cancer.

5. Nitrogenous wastes

The major sources of nitrogen-rich wastes are ammonia synthesis and nitrogen fertilizer industries, coal carbonization units, and amine production units. Out of this nitrogen waste accumulated in the soil due to excessive use of fertilizers, it is very toxic to the environment.

They drain into water bodies and destroy the ecosystem within them through the process of eutrophication. It also forms a dead zone in ponds, rivers, and in parts of the oceans where no life form can take place.

Gaseous nitrogenous waste is a component in the manufacture of smog

6. Ozone

Smog, the primary component of ozone, is produced when air pollutants are primarily composed of nitrogen oxides and volatile organic compounds in the presence of sunlight. Ozone is a toxic compound that affects the respiratory system due to asthma, emphysema, bronchitis, and increased COPD and lung cancer.

It also causes eye irritation, reduces immunity which makes the body susceptible to infections, and heart attacks. Reduced lifespan and Alzheimer’s risk. Low birth weight and spinal cord birth defects are also responsible for ozone pollution.

7. Sulfur Dioxide

This gas is released by power plants and other industries during the burning of fossil fuels. To some extent, this gas is released in locomotive ships and other vehicles, while removing metals from ores. When materials with high sulfur content are burnt, a sulfur oxide is released.

Sulfur combines with other molecules in the air to form particulate matter. They cause respiratory problems. The deposition of these particles on stone and other building surfaces causes staining and damage.

Sulfur Dioxide ide molecules in the air react with water vapor and form small droplets of dilute sulfuric acid. When it rains or naps, the rain takes down the acid and is called acid rain. It causes soil acidification on land water or in bodies of water.

When the chemical constitution of a substance changes, it affects the organisms and flora that live in it. Plants and leaves are wasted. Fishes die, so there are some species of frogs.

8. Radioactive waste

There are natural and man-made sources of radiation. Cosmic radiations from the sun’s rays carry high-energy electromagnetic radiation and continuously reach us from outer space.

Uranium mining releases radon-222 gas into the air. Radium-226 is present in rocks, sediments, and soils and emits a small amount of background radiation. Other naturally occurring radioactive elements are uranium, thorium, and isotopes of potassium and carbon.

Man-made sources of radiation are

  • Clinical medical applications such as X-rays and CT scans.
  • Nuclear test- During these tests radioactive dust is released into the air 6-7 km above the surface of the Earth and carried along with the air around the blast site. They settle on the ground by rain and from soil and water they enter the food chain where they cause serious health hazards.
  • Nuclear reactors and their waste- Radiation leakage from nuclear reactors is occurring despite the best design and proper handling techniques. Natural and accidental disasters also contribute to leakage. Indiscriminate disposal of radioactive fuel waste is also a source of radiation pollution. Plutonium-239 and uranium-235 have such long half-lives, that they can be expected to decay only after thousands of years and by then they emit radiation.

Genetic and non-genetic damage is done to the body. Genetic damage means mutations in gene structures that appear as deformities in future generations. Non-genetic changes include birth defects, various types of leukemia, tumors, miscarriages, and reproductive problems.

10. Other toxic pollutants

They cause benzene (gasoline), toluene, perchloroethylene (dry cleaning facilities), methylene chloride (used as a solvent or paint stripper), asbestos (in building materials), and other air pollution.

The leather tanning industry causes groundwater contamination in many countries due to improper disposal of untreated wastes during various tanning processes. In this chromium, hydrogen sulfide, ammonia, pesticides, pathogens, and fats constitute the major pollutants.

Processed foods industries add a lot of preservatives and additives to foods that make them last longer. Coloring agents and artificial sweeteners are not safe for anyone.


What are Pollutants?

Pollutants are the elements, molecules, and particles involved in pollution – life can be harmed when exposed to these materials, and their effects on humans and plants are well known. Pollutants can be introduced into the environment in many ways, both naturally and by humans.

What are the types of pollutants?

Different types of pollutants include:
1. Nitrogen oxides (NOx)
2. Sulfur oxides (SOx)
3. Particulate matter (PM)
4. Ground-level ozone (O3)
5. Volatile organic compounds (VOCs)
6. Mercury (Hg)
7. Peroxyacyl nitrates (PANs)
8. and more.

What is The definition of pollutants?

A pollutant is a substance or energy that is introduced into the environment and has undesirable effects or affects the usefulness of a resource. A pollutant can cause long-term or short-term damage by changing the growth rate of plant or animal species or by impairing human convenience, comfort, health, or property values.

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