pollution as a negative externality

First let’s define externality: Definition of 'Externality'
A consequence of an economic activity that is experienced by unrelated third parties. An externality can be either positive or negative.
(Ref: www.investopedia.com)

As an example of the above definition:
Pollution from a factory can affect the health of nearby residents – negative
The same factory can provide jobs to nearby residents – positive

Negative externality is two part: production and consumption. I will be using both these externalities in my following discussion on pollution.

Companies pollute on three different platforms: air, water and land.
Air pollution is caused by:
• Factories
• Power plants
• Vehicles
• Solvents
• Domestic/industrial chemicals
• Military
• Natural causes – volcano, wildfires
(ref: aboutairpollution.co.za)

Water pollution is caused by:
• Urbanization o Land disturbed from construction o Chemical pollution from mines, industries, etc o Inadequate sewage and treatment
• Deforestation
• Damming of rivers
• Destruction of wetlands
(ref: www.randwater.co.za)

Land pollution is caused by:
• Domestic, nuclear wastes and industrial wastes,
• deforestation
• human sewage
• mining and other factories
• increased mechanization
• Sewage discharged into rivers instead of being treated properly
• Sanitary/hazardous landfill seepage
• Cemeteries
• Scrap yards (waste oil and chemical drainage)
(ref: www.wikianswers.com)

You will note from the above that pollution is a hot topic and one of the most commonly used to define negative externality.
The above causes of pollution serve as a grim reminder of the visible and mostly invisible effect on the consumers. And it certainly is not calculated into the economy.

The costs and benefits of pollution can be calculated by economists but this will not reduce its impact, merely factor into the cost of production of goods.

What will impact on the economy is the demand for