Pollution is the introduction of unwanted substances into the natural environment that causes adverse effects on the environment. Pollution can be in the form of chemical substances or energy, such as noise, heat, or light. These pollution-causing agents are called pollutants. A Pollutant is an agent that pollutes the environment such as air, water, soil, noise among others. Pollutants can make their way up to the food chain and eventually find their way inside the human body causing severe health issues.

Types Of Pollution

There are different types of pollution, which are either caused by natural events (like forest fires) or by anthropogenic activities (like cars, factories, nuclear wastes, etc.) These are further classified into the following types of pollution-

  1. Air pollution
  2. Soil Pollution
  3. Noise Pollution

4.    Other types of pollution are Thermal pollution, Light pollution, and Radioactive pollution, these are  the deadliest and most dangerous types of pollution.

Air Pollution

Air pollution is the release of harmful unwanted substances that includes chemicals, toxic gases, harmful molecules into the earth’s atmosphere. These unwanted substances are quite detrimental and thus pose serious health issues in some cases. The agents which cause air pollution are called air pollutants.

These air pollutants are of two types-

1.     Primary Pollutants– The pollutants which directly cause air pollution are known as primary pollutants. Examples of primary pollutants are Oxides of sulfur, Oxides of carbon, nitrogen, methane, etc.

2.     Secondary Pollutants- The pollutants formed by intermixing of primary pollutants are called Secondary pollutants. Examples of secondary pollutants are Ozone, smog, etc.

Causes of Air Pollution-

1.     Burning of Fossil Fuels: The burning of fossil fuels emits a large amount of sulfur dioxide. Carbon monoxide released by the incomplete burning of fossil fuels also results in air pollution.

2.     Automobiles: The gases emitted from vehicles such as motorbikes, trucks, cars, buses, etc. pollute the environment. These gases play the role of greenhouse gases and also result in diseases among individuals.

3.     Agricultural Activities: Ammonia is considered to be the most hazardous gas emitted during agricultural activities. The insecticides, pesticides, weedicides, and fertilizers emit harmful chemicals into the atmosphere and contaminate it.

4.     Factories and Industries: Factories and industrial pollution are the main source of carbon monoxide, organic compounds, hydrocarbons, and chemicals. These are released into the air which results in degrading its quality.

5.     Mining Activities: In the mining process, the minerals which are present below the earth are extracted using large pieces of equipment. The dust and chemicals released during the process not only pollute the air but also worsen the health of the workers and people living in the nearby areas.

6.     Domestic Sources: The household products which are used for cleaning the house and paints contain toxic chemicals that are released into the air. Even the new painted house causes different health issues to humans and also to the environment due to chemicals present in them.

Effects of Air Pollution

The harmful effects of air pollution on the environment are:

  1. Diseases: Air pollution has caused several respiratory disorders and heart diseases among humans. Children living near industrial areas are more prone to pneumonia and asthma.
  2. Global Warming: Emission caused by greenhouse gases results in an imbalance of the gaseous composition of the air. This has caused an increase in the temperature of the earth. This increase in the temperature of the earth is known as global warming.
  3. Acid Rain: The combustion of fossil fuels releases harmful gases such as nitrogen oxides and sulfur oxides in the air. The water vapor in the atmosphere combines with these pollutants, becomes acidic, and fall as acid rain which damages human, animal and plant life.
  4. Ozone Layer Depletion: The release of chlorofluorocarbons (CFC), halons, and hydrochlorofluorocarbons in the atmosphere is the major cause of the depletion of the ozone layer. The depleting ozone layer causes the harmful UV-B rays coming from the sun and causes skin diseases and eye problems among individuals.
  5. Effect on Animals: The air pollutants suspend on the water bodies and affect the aquatic lifeforms.

Air Pollution Control

Some of the control measures are-

  1. Use of Public Transportation
  2. Energy Conservation
  3. Use of Energy Conservation
  4. Use of clean energy fuels.

Water Pollution

Water pollution can be defined as the impurity of water bodies. Water pollution is caused when water bodies such as rivers, lakes, oceans, groundwater, and aquifers get contaminated with industrial and agricultural effluents.


Causes of Water Pollution

The causes of water pollution may be both natural and anthropogenic. But, the most common causes of water pollution are the anthropogenic ones, including:

  1. Agrochemicals: Agrochemicals like fertilizers (containing nitrates and phosphates) and pesticides (insecticides, fungicides, herbicides, weedicides, etc.) washed by rainwater and surface runoff pollute water.
  2. Stormwater runoff: Carrying away various oils, petroleum products, and other contaminants from urban and rural areas (ditches). These usually form layers on the water
  3. Sewage: The discharge of sewage into the freshwater bodies causes water pollution.
  4. Mining activities: Mining activities involve the crushing of rocks that contain many traces of metals and sulfides. The leftover material because of mining activities may easily generate sulfuric acid in the presence of precipitation water.
  5. Industrial Effluents: Industrial wastes which contain toxic chemicals such as acids, alkalis, metallic salts, phenols, cyanides, ammonia, radioactive substances, etc., are sources of water pollution.
  6. Burning of fossil fuels: The emitted ash particles contain toxic metals (such as Silver or Lead). The combustion of these metals adds a series of oxides including carbon dioxide to air and, respectively, water bodies.
  7. Leaking landfills: May pollute the groundwater below the landfill with a large variety of impurities (whatever is stored by the landfill).

Effects of water pollution

The effects of water pollution are various. They include impure drinking water, poisonous food for animals (due to these organisms having bio-accumulative toxins from the environment over their life spans),  and many more. 

Control of Water Pollution

Water pollution is controlled by various methods-

1.) Rather than releasing sewage waste directly into water bodies it should be treated before being discharged. If the secondary treatment of water has been carried out, it can be reused in sanitary systems and agricultural fields. 

2.) A special plant, the Water Hyacinth can absorb dissolved toxic chemicals such as cadmium and other such elements.

Soil Pollution

Soil pollution is defined as the presence of contaminants in the soil in such high concentrations that it poses a risk to human health or the ecosystem.

Causes of Soil Pollution

There is numerous cause of soil pollution that can be natural or anthropogenic causes.

  1. Natural Pollution of Soil: Sometimes, some pollutants are naturally accumulated in soils. This may be due to the differential deposition of soil by the atmosphere. Another way through which this type of soil pollution can occur is via the transportation of soil pollutants with precipitation water.
  2. Anthropogenic Soil Pollution: Various man-made activities also lead to the cause the contamination of soil.
  3. Pesticides: Earlier, the chemical nicotine which is present in the tobacco plants was used as the pest controlling substance in agricultural practices. However, DDT was found to be extremely useful for malaria control and pest control of many insects but a high concentration of pesticides may cause soil pollution.
  4. Inorganic Fertilizers: Excessive use of inorganic nitrogen fertilizers leads to acidification of soil and thus contaminates the agricultural soil.

Effects of Soil Pollution

Soil Pollution leads to various health issues and also affects the environment. Some of  the effects of Soil Pollution are that it leads to

  1. Respiratory disorders
  2. Skin disease
  3. Other health-related issues

Control of Soil Pollution

Several technologies have been developed to tackle soil pollution. Some of the important methods to be followed for the decontamination of polluted soil are listed below-

1. Excavation and subsequent transportation of polluted soils to faraway locations. 

2. Extraction of pollutants via thermal remediation – This occurs as the temperature is raised in order to force the contaminants into the vapour phase, after which they can be collected through vapour extraction. 

3. Bioremediation or phytoremediation involves the use of microorganisms and plants for the sterilization of soil.

4. Mycoremediation involves the use of fungi to sterilize the soil. 

Noise Pollution

Noise pollution refers to the excessive amount of noise in the surrounding that tends to disrupt the natural balance. Generally, any sound which is over 85 decibels is considered to be harmful. Also, the duration an individual is exposed to loud music also impacts their health. Normal talking is around 60 decibels, and a jet taking off is around 150 decibels. 

Causes of Noise Pollution

Following are the causes and sources of noise pollution:

  1. Industrialization: Industrialization has led to an increase in noise pollution as use of heavy machinery such as generators, transformers, mills, and huge exhaust fans are used, resulting in the production of unwanted noise.
  2. Vehicles: Increased number of vehicles on the roads is also the reason for noise pollution.
  3. Events: Weddings and the public get together involve loudspeakers to play music resulting in the production of unwanted noise in the neighborhood.
  4. Construction sites: Mining, construction of buildings, quarrying  add to the noise pollution.

Effects of Noise Pollution 

Noise pollution can be hazardous to human health in the following ways:

  1. Hypertension: Long duration of exposure to a high volume of music results in elevated blood pressure.
  2. Hearing loss: Constant exposure of human ears to loud noise that is beyond the range of sound that human ears can damage the membrane of the ear resulting in loss of hearing.
  3. Sleeping disorders: Lack of sleep might result in tiredness and low energy level throughout the day affecting everyday activities.

Control Of Noise Pollution

Some noise pollution preventive measures are provided in the points below.

  1. Honking at sensitive prone areas like teaching institutes, hospitals, etc. should be banned.
  2. Adequate soundproof systems should be installed in specific areas.
  3. Musical instruments’ sounds can be used to control desirable limits.
  4. Dense tree cover is useful in noise pollution as they have the capacity to absorb noise to some extent.


This Post Has 11 Comments

    1. David Muli

      A green economy is needed as ‘Felix Atiang’ comments. We should think and resolve to the ways of restoring back our environment to green as before.

    1. David Muli

      True to say. Consequently, read the next article of the ways and the home-based ingredients used to lessen toxic levels of pollutants in our environmental waste specifically.

  1. Davenport Reuben

    Taking care of the environment is crucial

  2. Caroline Njeri

    The pollution in cities also leads to eye problems like the dry eye syndrome or Conjunctival disease. The reality is that all this pollution is killing us as well. But change is hard, so the problem persists.

    1. David Muli

      Caroline njeri, thank you for the add up. I appreciate. Together, let’s fight pollution.

  3. Carson Anekeya

    Great insight, we really have to take control measures towards this if we really need a green economy.

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