Pollution – Sources and Effects

Environmental pollution had been a fact of life for many centuries but it became a real problem since the start of the industrial revolution.

We discuss major aspects of this study area, from definitions to pollution types & sources as well as wide-ranging pollution effects.

So what is pollution? In order to get a better understanding of it, let’s have a look at some common definitions.

oil pollution emissions
Oil Pollution Emissions © Graeme MacLean

Environmental pollution is “the contamination of the physical and biological components of the earth/atmosphere system to such an extent that normal environmental processes are adversely affected”. (Ref. 1)

Pollution is the introduction of contaminants into the environment that causes harm or discomfort to humans or other living organisms, or that damage the environment” which can come “in the form of chemical substances, or energy such as noise, heat or light”. “Pollutants can be naturally occurring substances or energies, but are considered contaminants when in excess of natural levels.” (Ref. 2)

Pollution is “the addition of any substance or form of energy (e.g., heat, sound, radioactivity) to the environment at a rate faster than the environment can accommodate it by dispersion, breakdown, recycling, or storage in some harmless form”. (Ref. 3)

Pollution is a special case of habitat destruction; it is chemical destruction rather than the more obvious physical destruction. Pollution occurs in all habitats—land, sea, and freshwater—and in the atmosphere.” (Ref. 4)

“Much of what we have come to call pollution is, in reality, the nonrecoverable matter resources and waste heat.” (Ref. 5)

“Any use of natural resources at a rate higher than nature’s capacity to restore itself can result in pollution of air, water, and land.” (Ref. 6)

Pollution is habitat contamination”. (Ref. 7)

environmental pollution

Perhaps the overriding theme of these definitions is the ability of the environment to absorb and adapt to changes brought about by human activities.

In one word, environmental pollution takes place when the environment cannot process and neutralize harmful by-products of human activities (for example, poisonous gas emissions) in due course without any structural or functional damage to its system.

In fact, “the due course” itself may last many years during which nature will attempt to decompose the pollutants; in one of the worst cases – that of radioactive pollutants – it may take as long as thousands of years for the decomposition of such pollutants to be completed.

Pollution occurs, on the one hand, because the natural environment does not know how to decompose the unnaturally generated elements (i.e., anthropogenic pollutants), and, on the other, there is a lack of knowledge on the part of humans on how to decompose these pollutants artificially.

Why does pollution matter?

It matters first and foremost because it has negative impacts on crucial environmental services such as the provision of clean air and clean water (and many others) without which life on Earth as we know it would not exist.

Introduction to Environmental Pollution

Although pollution had been known to exist for a very long time (at least since people started using fire thousands of years ago), it had seen the growth of truly global proportions only since the onset of the industrial revolution during the 19th century.

environmental pollution england 19th century
Environmental Pollution England, 19th Century Courtesy: Wikimedia.org

The industrial revolution brought with it technological progress such as the discovery of oil and its virtually universal use throughout different industries.

Technological progress facilitated by super efficiency of capitalist business practices (a division of labor – cheaper production costs – overproduction – overconsumption – overpollution) had probably become one of the main causes of serious deterioration of natural resources.

At the same time, of course, development of natural sciences led to a better understanding of negative effects produced by pollution on the environment.

Environmental pollution is a problem both in developed and developing countries. Factors such as population growth and urbanization invariably place greater demands on the planet and stretch the use of natural resources to the maximum.

It has been argued that the carrying capacity of Earth is significantly smaller than the demands placed on it by large numbers of human populations. And overuse of natural resources often results in nature’s degradation.

It’s interesting to note that natural resources had been stored virtually untouched in the Earth for millions of years.

Also Check Out →  Causes of Pollution

But since the start of the industrial revolution vast amounts of these resources had been exploited within a period of just a couple of hundred of years at unimaginable rates, with all the waste from this exploitation going straight into the environment (air, water, land) and seriously damaging its natural processes.

Environmental Pollutants:
What Are They & How Do They Decompose?

Environmental pollutants are constituent parts of the pollution process. They are the actual “executing agents” of environmental pollution.

They come in gaseous, solid or liquid form.

It is interesting to note that, as of 1990, there were around 65,000 different chemicals in the marketplace, i.e. potential environmental pollutants that were to be released into air, water and land on a regular basis. (Ref. 8)

We assume that, as of 2011 – 2012, this number may be significantly higher.

Renowned author Miguel A. Santos identifies at least three general characteristics of environmental pollutants (Ref. 9):

beach pollution, malaysia
Beach pollution in Malaysia which travels from China © epSos.de
  • Pollutants don’t recognize boundaries, i.e. they are transboundary;
  • Many of them can’t be degraded by living organisms and therefore stay in the ecosphere for many years; and
  • They destroy biota and habitat.

These points emphasize that pollutants present a serious long-term global problem that affects more or less every country and, therefore, can only be solved by a coordinated set of actions and unwavering commitment of nations to international environmental agreements.

In order to develop and implement an effective international policy for pollutants’ management, it is important, among other factors, to understand their decomposition mechanisms.

We know that decomposition of pollutants can occur either biologically or physicochemically. (Ref. 10)

Biological Decomposition of Environmental Pollutants

Santos divides environmental pollutants into biodegradable and non-biodegradable ones, and describes them as follows. (Ref. 11)

Biodegradable Pollutants

pomelo peel, biodegradable pollutant
Fruit peel is biodegradable © Fotoos Van Robin

Biodegradable pollutants are the ones that can be broken down and processed by living organisms, including organic waste products, phosphates, and inorganic salts.

For example, if a pollutant is organic, it can be used by a living organism to obtain energy and other material from carbohydrates, proteins etc.

Therefore, biodegradable pollutants are only “temporary nuisances” that can be neutralised and converted into harmless compounds.

However, it is important to remember that they can become serious pollutants if released in large amounts in small areas, thus exceeding the natural capacity of the environment to “assimilate” them.

Non-Biodegradable Pollutants

plastic glasses, non biodegradable pollutant
Plastic may look beautiful but it is not biodegradable © Nolte Lourens

Non-biodegradable pollutants are the ones that cannot be decomposed by living organisms and therefore persist in the ecosphere for extremely long periods of time.

They include plastics, metal, glass, some pesticides and herbicides, and radioactive isotopes.

In addition to that, fat soluble (but not water soluble) non-biodegradable pollutants, ex. mercury and some hydrocarbons, are not excreted with urine but are accumulated in the fat of living organisms and cannot be metabolised.

Non-Biological Decomposition of Environmental Pollutants (Ref. 12)

Non-biological decomposition of non-biodegradable pollutants requires a combination of many factors, such as wind, water, and climate to work together to achieve neutralization of pollutants.

Some of the most dangerous pollutants such as radioactive isotopes can decompose by themselves but it will take them thousands of years.

Removal of Air Pollutants from the Atmosphere (Ref. 13)

Air pollutants, as opposed to solid and liquid pollutants found on land and in water, may be removed from the atmosphere through wet deposition or dry deposition.

In case of wet deposition, pollutants make way into clouds or other precipitation and then get deposited onto the surface of the Earth by way of rain. In case of dry deposition, pollutants are deposited directly onto the planet’s surface and vegetation, such as plants and trees of tropical rainforests.

We may assume that once air pollution has been deposited onto the planet’s surface, the normal rules of biological and non-biological decomposition for other types of pollutants will apply.

Types of Environmental Pollution

Generally speaking, there are many types of environmental  pollution but the most important ones are:

  • Air pollution
  • Water pollution
  • Soil pollution (contamination)

Some of the most notable air pollutants are sulfur dioxide, nitrogen dioxide, carbon monoxide, ozone, volatile organic compounds (VOCs) and airborne particles, with radioactive pollutants probably among the most destructive ones (specifically when produced by nuclear explosions).

Our Air Pollutants article provides a clear overview of the sources and effects of these air pollutants.

Water pollutants include insecticides and herbicides, food processing waste, pollutants from livestock operations, volatile organic compounds (VOCs), heavy metals, chemical waste, and others.

Some soil pollutants are: hydrocarbons, solvents, and heavy metals.

So where does environmental pollution come from?

Sources of Environmental Pollution

Fossil Fuel Sources of Environmental Pollution

fossil fuel pollution
Oil Pollution © Rachel Scopes

In modern industrialized societies, fossil fuels (oil, gas, coal) transcended virtually all imaginable barriers and firmly established themselves in our everyday lives.

Also Check Out →  Air Pollutants: Sources and Effects

Not only do we use fossil fuels for our obvious everyday needs (such as filling a car), as well as in the power-generating industry, they (specifically oil) are also present in such products as all sorts of plastics, solvents, detergents, asphalt, lubricating oils, a wide range of chemicals for industrial use, etc. (Ref. 14)

Combustion of fossil fuels produces extremely high levels of air pollution and is widely recognized as one of the most important “target” areas for reduction and control of environmental pollution.

Fossil fuels also contribute to soil contamination and water pollution. For example, when oil is transported from the point of its production to further destinations by pipelines, an oil leak from the pipeline may occur and pollute soil and subsequently groundwater. When the oil is transported by tankers by the ocean, an oil spill may occur and pollute ocean water.

Of course, there are other natural resources whose exploitation is a cause of serious pollution; for example, the use of uranium for nuclear power generation produces extremely dangerous waste that would take thousands of years to neutralize.

But there is no reasonable doubt that fossil fuels are among the most serious sources of environmental pollution.

Power-generating plants and transport are probably the biggest sources of fossil fuel pollution.

Common sources of fossil fuel pollution are: (Ref. 15)


  • Power-generating plants
  • Petroleum refineries
  • Petrochemical plants
  • Production and distribution of fossil fuels
  • Other manufacturing facilities


  • Road transport (motor vehicles)
  • Shipping industry
  • Aircraft

Fossil fuel combustion is also a major source of carbon dioxide (CO2) emissions and perhaps the most important cause of climate change. Learn more about the causes and effects of global warming here.

Other (Non-Fossil Fuel) Sources of Environmental Pollution

agricultural pollution
© Constantin Opris

Among other pollution sources, agriculture (livestock farming) is worth mentioning as the largest generator of ammonia emissions resulting in air pollution.

Chemicals such as pesticides and fertilizers are also widely used in agriculture, which may lead to water pollution and soil contamination as well.

Trading activities may be another source of environmental pollution.

For example, it’s been recently noted that packaging of products sold in supermarkets and other retail outlets is far too excessive and generates large quantities of solid waste that ends up either in landfills or municipal incinerators leading to soil contamination and air pollution.

Residential sector is another significant source of pollution-generating solid municipal waste that may end up in landfills or incinerators leading to soil contamination and air pollution.

Our unique analysis of Causes of Pollution will give you an excellent perspective on the fundamental pollution drivers such as globalization, industrialization and population growth.

You will also learn about why we refer to production and consumption as primary & secondary causes of environmental pollution; plus get a schematic presentation of pollution sources – i.e., actual economic sectors such as manufacturing, power generation, residential sector and so on.

Since air pollution is one of the largest areas of environmental pollution studies, our discussion on Air Pollution Causes explains how each major pollutant contributes specifically to air pollution.

Environmental Pollution Effects

Environmental pollution effects can be truly damaging.

Please read our detailed analysis of all types of Pollution Effects here, where we discuss the effects of air pollution, water pollution, and soil pollution.

Some of the effects of air pollution include asthma, reduced energy levels, irritation of eyes, disruption of the immune system, malfunction of the central nervous system, cancer.

For a further in-depth analysis of Air Pollution Effects, please see here.

Water pollution can cause skin rashes & allergies, all sorts of water-borne infections, vomiting & stomach aches, malfunction of the central nervous system and so on.

Soil pollution is, in a way, connected to water pollution and may cause cancer, headaches, fatigue, skin rashes and so on.

Environmental Pollution – Conclusion

Environmental pollution is causing a lot of distress not only to humans but also animals, driving many animal species to endangerment and even extinction.

hollywood pollution
Pollution is Not Glamorous © Caleb Coppola

The transboundary nature of environmental pollution makes it even more difficult to manage it – you cannot build brick walls along the borders of your country or put customs cabins at every point of entry to regulate its flows into your country.

Everything on our planet is interconnected, and while nature supplies us with valuable environmental services without which we cannot exist, we all depend on each other’s actions and the way we treat natural resources.

It’s widely recognized that we are hugely overspending our current budget of natural resources – at the existing rates of its exploitation, there is no way for the environment to recover in good time and continue “performing” well in the future.

Perhaps we should adopt a holistic view of nature – it is not an entity that exists separately from us; nature is us, we are an inalienable part of it, and we should care for it in the most appropriate manner. Only then can we possibly solve the problem of environmental pollution.