Intro to Pollution

Pollution: Refers to both artificial and natural materials that are created, consumed, and discarded in an unsustainable manner.

Pollutant: Harmful elements which cause pollution. They are the elements, molecules and particles involved in pollution - life can be harmed when exposed to these materials, and the effects of them on humans and plants are well known.

Environmental pollution may destabilize development process and competitiveness of developing nations whose economies depends on natural resources.

Fundamental Causes of Pollution

• Industrialization is the first fundamental cause of pollution. Among other things, industrialization set in motion the widespread use of fossil fuels (oil, gas and coal) which are now the main sources of pollution. Industrial pollution contribute majorly in emitting waste gases like carbon monoxide, Sulphur oxides, and nitrogen oxides which are the waste products of industry and end up in the air as well as dumping of industrial waste into water, endangering human life.

• Urbanization is the second fundamental cause of pollution. With population numbers 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 level of pollution.

• Globalization is another cause of pollution. Globalization has become an effective facilitator of environmental degradation.

Introduction of Pollutants to Environment

Pollutants can be introduced into the environment in many ways, both naturally and by humans. Pollutants are of mainly two types, primary and secondary.

Primary Pollutants: They are emitted directly into the environment.

Secondary Pollutants: They are formed from primary pollutants and external factors.

Types of Pollutants

• Nitrogen oxides (NOx)

• Sulfur Oxides (SOx)

• Particulate matter (PM)

• Ground level ozone

• Volatile organic compounds (VOCs)

• Mercury (Hg)

• Peroxyacyl nitrates (PANs)

Air Pollution

Air pollution: It is the introduction of harmful chemicals into the atmosphere. The exhaust from vehicles for instance, is polluting the air with toxic chemicals such as carbon monoxide and formaldehyde.

Smog

Smog: It is air pollution which reduces visibility. Ex: Shanghai smog, The great smog of London (1952).

Higher levels of smog are associated with a wide range of diseases such as chronic obstructive pulmonary disorder, heart disease, stroke and lung cancer.

Soil Pollution

Xenobiotic

Xenobiotics: They are defined as chemicals to which an organism is exposed that are extrinsic to the normal metabolism of that organism.

Ex: poly aromatic hydrocarbons (PAHs), persistent organic pollutants (POPs)

Recalcitrants

Recalcitrants: They are pollutants that persist in the environment, they are capable of long range transportation, bioaccumulation, in human and animals, and biomagnifications in food chain.

Long range transport: It refers to the transport by the wind of air pollutants or their precursors from the areas where they were emitted to other locations at downwind distances of 100 km or more.

Landfills

Landfills are well-engineered facilities designed to receive specific kinds of waste, including municipal solid waste, construction and demolition debris and hazardous waste.

Water Pollution

Water pollution happens when toxic substances enter water bodies such as lakes, rivers, oceans and so on, getting dissolved in them, lying suspended in the water or depositing on the bed. This degrades the quality of water.

Industrial Runoff

Stormwater and industrial runoff is a leading cause for water pollution. Industrial runoff typically contains high concentrations of pollutants such as heavy metals and petroleum hydrocarbons.

Oil Spill

Oil Spill: It refers to any uncontrolled release of crude oil, gasoline, fuels, or other oil by-products into the environment.

The Deepwater Horizon oil spill was an industrial disaster that began on April 20, 2010, in the Gulf of Mexico on the BP-operated Macondo Prospect, considered to be the largest marine oil spill in the history of the petroleum industry

Pollution Control

Pollution Control: It is the process of reducing or eliminating the release of pollutants into the environment.

It is regulated by various environmental agencies which establish pollutant discharge limits for air, water, and land. Recycling, for instance, is becoming more common. In recycling, trash is processed so its useful materials can be used again.

Air Pollution Control

Air pollution Control strategies can be divided into two categories:

• The control of particulate emissions

• The control of gaseous emissions

Water Pollution Control

Water pollution control methods can be subdivided into physical, chemical, and biological treatment systems. Most treatment systems use combinations of any of these three technologies. Additionally, water conservation is a beneficial means to reduce the volume of wastewater generated.

Soil Pollution Control

Solid pollution control methods which are typically used include landfilling, composting , and incineration