Causes of Pollution

By Irina Bright.

This article is part of our Environment section

See the complete list of all our Pollution Articles here.

We classify anthropogenic causes of pollution as the ones which originate from excessive levels of production (processing) and consumption of physical resources.


environment, sun, mountains Photo: Grant Ritchie

1. Introduction

2. Fundamental Pollution Drivers

3. Primary & Secondary Pollution Causes

4. Sources of Pollution

      Production Side
      Consumption Side

5. Pollution Agents




What exactly are causes of pollution? Let's try to define the concept of pollution first.

Here are just a couple of definitions:

Pollution is the introduction of contaminants into the environment that cause harm or discomfort to humans or other living organisms, or that damage the environment. (Ref. 1)

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. 2)

We can expand the second definition and conclude that pollution takes place because:

  • we process, consume and throw away a high volume of material resources at a very high rate, and
  • the nature's own rate of re-absorbing these resources back into its structure and effectively neutralizing them is much slower than our rates of production / consumption.

So it is not just the concepts of production & consumption but excessive production & consumption which are the major contributors to man-caused pollution.

To add to that, it is not only excessive production but also inefficient & dirty methods of production which become sources of environmental pollution.

And it is not only excessive consumption but also careless & thoughtless disposal of post-consumption waste resources which could otherwise be recycled.

Our analysis of causes of pollution focuses on:

  • fundamental drivers of pollution,
  • primary & secondary causes of pollution, and
  • sources of pollution.

Here is its schematic presentation:

drivers, causes, sources, pollution

We start the discussion with the fundamental drivers of pollution.

Fundamental Pollution Drivers

fundamental pollution causes, industrialization, population growth, globalization Fundamental Pollution Causes

The humanity had known pollution, to some extent or another, at least since the times the fire had been invented.

But it was only with the onset of the industrial revolution in the 19th century that people realized the seriousness of the pollution problem and its often devastating effects.

In the last 200 years or so there appeared several fundamental trends which became the major forces behind the surge in levels of air, water & land pollution throughout the globe.

Industrialization is the first fundamental cause of pollution. Among other things, industrialization set in motion the widespread use of fossil fuels (oil, gas & coal) which are now the main sources of pollution.

Population growth is the second fundamental pollution cause. With population numbers literally exploding around the world, the demand for food and other goods goes up. This demand is met by expanded production and use of natural resources, which in turn leads to higher levels of pollution.

pollution causes, shanghai traffic, population growth Shanghai Traffic
© Jakob Montrasio

Globalization is another major cause of pollution. Globalization has become an effective facilitator of environmental degradation. Developing countries usually have much looser laws on environmental protection. With this “benefit” as well as the population growth and easy availability of cheap labor, big industry prefers to move its facilities to such “pollution havens” rather than work in more regulated markets.

So we won’t be wrong if we consider industrialization, population growth and globalization the fundamental drivers of pollution, the very roots of the gigantic pollution tree.

(Ref. 3)

Primary and Secondary Causes of Pollution

Taking a step down from the fundamental drivers, we can now approach production & consumption as primary & secondary causes of pollution.

pollution causes Causes of Pollution

We refer to PRODUCTION as the primary cause of pollution because the whole cycle of extracting and processing natural resources and then selling processed goods starts from this point. And it obviously comes before consumption.

The diagram above is a basic presentation of major sectors which comprise numerous polluting sub-sectors.

The production side of the diagram includes manufacturing industries, power generation, road, rail & air transport and agriculture & timber production. In reality, it can be of course broken down into many other industries / sub-industries.

So how does the production side contribute to global pollution?

Let's consider the following example.

A car is a necessity for many people who use it in their everyday lives. In order to produce cars, a car manufacturer needs to:

  • Purchase raw materials such as metal, rubber, plastic, wood, paint etc. Raw materials are extracted from earth in large amounts often damaging the natural system of the area from which they were extracted, as well as surrounding areas, ex. rainforests.
  • Purchase energy / electricity which is usually generated from petroleum resources. Petroleum-based energy generation causes the emission of gases into the atmosphere and often contaminates water and land of the surrounding areas.
  • Use this energy to process raw materials into cars. Cars are manufactured leaving behind an environmentally destructive footprint as described above.

That is a very simplified explanation of how manufacturing contributes to environmental pollution.

We'll now have a look at consumption.

We refer to CONSUMPTION as the secondary cause of pollution because this stage comes after, and depends on, production.

The consumption side of the diagram includes individual consumers as well as residential, commercial & social sectors which utilize the goods offered by the production side.

And how does the consumption side contribute to global pollution?

Let's continue with the example of the car. Each car owner needs to:

wind mills, car pollution Clean Energy Alongside Car Pollution
Photo: Kevin Dooley
  • Fill it with gas / petrol every week to operate it. The burning of petrol causes the emission of dirty gases straight into the atmosphere. Such air pollution then travels globally affecting many different parts of the planet.
  • Wash it regularly with detergents - either manually or in a car wash. Car detergents are often made of harmful chemicals which, when used, are released directly into the environment, ex. via waste water.
  • Change tires on a regular basis. A significant percentage of each tire's composite material comes from petroleum derivatives and other chemicals. Old tires often end up unrecycled and thrown into landfills releasing harmful chemicals onto surrounding land areas and into the air and thus contributing to air & land pollution. Going back to the production side, the more often tires need to be changed, the more natural resources will need to be allocated yet again for their production and the more pollution will be released into the environment.
  • Owners of new cars are exposed to "in-car" pollution which is almost always ignored by the public. In-car pollution is caused by the offgassing of chemicals from freshly-produced car components. In this case, the health of new car owners suffers alongside the health of the wider environment.

That is another simplified explanation of how consumption becomes a significant cause of pollution.

So production and consumption are the basic causes of pollution.

If that is the case, then each industry / sector that "belongs" either to production or consumption becomes a source of pollution.

Let's look at pollution sources in more detail below.

Sources of Pollution

Production Side

When we think of pollution, the first thing that naturally comes to mind is manufacturing.

And that is no surprise. Images of enormous chimneys emitting heavy dirty fumes into the air are very powerful indeed, and are directly associated with pollution.

Manufacturing includes numerous industries which are in fact sources of all types of pollution - air, land and water.

We have grouped manufacturing industries into 5 large sectors, as you can see in the diagram below:

manufacturing, sources, pollution Manufacturing Sources of Pollution

So each of these sectors including their own sub-sectors is a source of pollution:

  • Raw materials extraction
  • Raw materials processing
  • Heavy industry (ex. equipment manufacturing and transport manufacturing)
  • Light industry (ex. textiles and pulp & paper)
  • Construction

This classification aims to give us an idea of the "pollution's points of origin" from the manufacturing perspective. It is in no way an exhaustive list of polluting industries.

Power generation is another huge source of pollution which is nowadays associated with smoky chimneys even more than manufacturing.

The classical example here is the burning of fossil fuels to generate power. Carbon dioxide and other harmful gases are emitted in the process and cause serious ecological damage for many years to come.

Nuclear power is far from being a clean source of energy, even though its lobbyists may claim so. The toxic radioactive waste produced as a result of its generation takes thousands of years to decompose and become harmless. So don't fall for the lie of looking at nuclear as a "green" source of energy just because it doesn't emit greenhouse gases into the atmosphere.

power generation, pollution

So here are some major sources of pollution from the power-generation sector:

  • Fossil fuel-based energy

    • Oil-based generation
    • Gas-based generation
    • Coal-based generation
  • Nuclear Energy

    • Uranium-based generation

Public transport & shipping are also significant contributors to global pollution levels. All of them use fossil fuels for operation. Rail transport is probably the cleanest of all the types, and air transport is assumed to be one of the least efficient ones.

public transport, pollution

Sources of pollution by types of transportation:

  • Road transport
  • Rail transport
  • Air transport
  • Sea shipping

The public often doesn't realize just how significant a source of pollution agriculture & timber production have become.

Livestock farming uses vast amounts of resources and produces a lot of waste. Harmful fertilizers are widely used to grow cereals and other plants - such chemicals affect negatively the wider environment as well as human health.

Timber production is a major cause of global deforestation which releases carbon dioxide into the atmosphere.

agriculture, pollution

Sources of pollution from the agricultural sector:

  • Livestock / cattle farming
  • Cereals & other plants growing
  • Timber production

Consumption Side

While production sectors are obvious examples of "pollution creation", consumption presents a more subtle side to this issue.

When we look at individual consumers, a lot of pollution comes from landfill disposal of post-consumption waste which could actually be recycled. At the same time, there are many consumer goods which cannot be recycled - and they end up on the landfill as well.

As for the wider residential sector, domestic gas heating systems and private transport are no doubt some of the major contributors to global pollution. On top of that, many residential items which can or cannot be recycled (ex., domestic furniture) are also sent to landfills.

individual consumers, pollution
residential sector, pollution

Sources of pollution by individual consumers and residential sector:

  • Food
  • Clothing
  • Other personal goods
  • Private housing
  • Private transport

We have a similar situation with the commercial & social sectors. Any waste generated from the use of premises as well as transportation all contribute to pollution levels in many different ways.

The social sector may include both governmental and non-governmental organizations.

commercial sector, pollution
social sector, pollution

Sources of pollution by commercial & social sectors:

  • Commercial premises
  • Commercial transport
  • Governmental & non-governmental bodies' premises
  • Transport for use by governmental & non-governmental bodies

Pollution Agents

We refer to pollution agents as the chemicals which are released into the environment as part of the waste products generated from production and consumption activities.

In other words, pollution agents are the "operators" which make pollution "happen".

They are also known as environmental pollutants, air pollutants and so on. Some of them are carbon dioxide, sulfur dioxide, nitrogen oxides.

Feel free to learn more about environmental pollutants by further exploring our website.

PS. Please note that there are also natural causes of pollution, ex. forest fires and volcano eruptions, but the focus of this article has only been on causes of pollution brought about by human activity.

Written by:     Irina Bright
Original publication date:     2011
Republication date:     2020


1. Pollution. (March 16, 2008). In Wikipedia, The Free Encyclopedia. Retrieved April 3, 2008 from

2. Santos, M. A. (1990). Managing Planet Earth: Perspectives on Population, Ecology, and the Law. Westport, CT: Bergin & Garvey, p. 44. Retrieved April 3, 2008 from

3. Ehrlich, P. R., Ehrlich, A. H., & Holdren, J. P. (1977). Ecoscience: Population, Resources, Environment. San Francisco: W. H. Freeman, p. 536. Retrieved November 22, 2008 from