CAUSES OF AIR POLLUTION

There are many different chemical substances that contribute to air pollution.  These chemicals come from a variety of sources. Among the many types of air pollutants are nitrogen oxides, carbon monoxides, and organic compounds that can evaporate and enter the atmosphere. Air pollutants have sources that are both natural and human.  Now, humans contribute substantially more to the air pollution problem. Forest fires, volcanic eruptions, wind erosion, pollen dispersal, evaporation of organic compounds, and natural radioactivity are all among the natural causes of air pollution. Usually, natural air pollution does not occur in abundance in particular locations.  The pollution is spread around throughout the world, and as a result, poses little threat to the health of people and ecosystems. Though some pollution comes from these natural sources, most pollution is the result of human activity.  The biggest causes are the operation of fossil fuel-burning power plants and automobiles that combust fuel.   Combined, these two sources are responsible for about 90% of all air pollution in the United States. Some cities suffer severely because of heavy industrial use of chemicals that cause air pollution.  Places like Mexico City and Sao Paulo have some of the most deadly pollution levels in the world.

CAUSES OF WATER POLLUTION

In developed countries, sewage often causes problems when people flush chemical and pharmaceutical substances down the toilet. When people are ill, sewage often carries harmful viruses and bacteria into the environment causing health problems.

SEWAGE AND WATER WASTE

  Sewage is the term used for wastewater that often contains faeces, urine and laundry waste.

There are billions of people on Earth, so treating sewage is a big priority.

Sewage disposal is a major problem in developing countries as many people in these areas don’t have access to sanitary conditions and clean water.

Untreated sewage water in such areas can contaminate the environment and cause diseases such as diarrhoea.

Sewage in developed countries is carried away from the home quickly and hygienically through sewage pipes.

Sewage is treated in water treatment plants and the waste is often disposed into the sea.

Sewage is mainly biodegradable and most of it is broken down in the environment.

EXAMPLES OF AIR POLLUTIONS

SOUND POLLUTIONS

1. Noise Pollution or Sound Pollution is when the exposure of people or animals to levels of sound that are annoying, stressful, or damaging to the ears.
2. Although loud and frightening sounds are part of nature, only in recent centuries has much of the world become urban, industrial, and chronically noisy. The machines used in factories make noise throughout the day, and this disturbs the peaceful atmosphere in the vicinity, as machines used without proper covering lead to sound pollution. 
3. Noise is one of the most pervasive pollution in America. Noise intensity is measured in decibel units. The decibel scale is logarithmic; each 10-decibel increase represents a tenfold increase in noise intensity.
4. Most noise pollution comes from machines, especially automobiles, trucks, and aircraft. Construction equipment, farm machines, and the din of machinery inside factories can be dangerously loud. 
5. Some home appliances, shop tools, lawnmowers, and leaf blowers can also be noisy, as are guns, firecrackers, and some toys.
6. Even music, when played at very high volume, particularly through personal headphones, is as damaging to the ears as a roaring chain saw.

WATER POLLUTIONS

Water Pollution

Water pollution occurs when a body of water is adversely affected due to the addition of large amounts of materials to the water. The sources of water pollution are categorized as being a point source or a non-source point of pollution. Point sources of pollution occur when the polluting substance is emitted directly into the waterway. A pipe spewing toxic chemicals directly into a river is an example. A non-point source occurs when there is runoff of pollutants into a waterway, for instance when fertilizer from a field is carried into a stream by surface runoff.  

Types of Water Pollution
Toxic Substance -- A toxic substance is a chemical pollutant that is not a naturally occurring substance in aquatic ecosystems. The greatest contributors to toxic pollution are herbicides, pesticides and industrial compounds. 

Organic Substance -- Organic pollution occurs when an excess of organic matter, such as manure or sewage, enters the water. When organic matter increases in a pond, the number of decomposers will increase. These decomposers grow rapidly and use a great deal of oxygen during their growth. This leads to a depletion of oxygen as the decomposition process occurs. A lack of oxygen can kill aquatic organisms. As the aquatic organisms die, they are broken down by decomposers which leads to further depletion of the oxygen levels. 

A type of organic pollution can occur when inorganic pollutants such as nitrogen and phosphates accumulate in aquatic ecosystems. High levels of these nutrients cause an overgrowth of plants and algae. As the plants and algae die, they become organic material in the water. The enormous decay of this plant matter, in turn, lowers the oxygen level. The process of rapid plant growth followed by increased activity by decomposers and a depletion of the oxygen level is called eutrophication.

Thermal Pollution -- Thermal pollution can occur when water is used as a coolant near a power or industrial plant and then is returned to the aquatic environment at a higher temperature than it was originally. Thermal pollution can lead to a decrease in the dissolved oxygen level in the water while also increasing the biological demand of aquatic organisms for oxygen. 

Ecological Pollution -- Ecological pollution takes place when chemical pollution, organic pollution or thermal pollution are caused by nature rather than by human activity. An example of ecological pollution would be an increased rate of siltation of a waterway after a landslide which would increase the amount of sediments in runoff water. Another example would be when a large animal, such as a deer, drowns in a flood and a large amount of organic material is added to the water as a result. Major geological events such as a volcano eruption might also be sources of ecological pollution. 

AIR POLLUTIONS

Air is the ocean we breathe. Air supplies us with oxygen which is essential for our bodies to live. Air is 99.9% nitrogen, oxygen, water vapor and inert gases. Human activities can release substances into the air, some of which can cause problems for humans, plants, and animals.

There are several main types of pollution and well-known effects of pollution which are commonly discussed. These include smog, acid rain, the greenhouse effect, and "holes" in the ozone layer. Each of these problems has serious implications for our health and well-being as well as for the whole environment.

One type of air pollution is the release of particles into the air from burning fuel for energy. Diesel smoke is a good example of this particulate matter . The particles are very small pieces of matter measuring about 2.5 microns or about .0001 inches. This type of pollution is sometimes referred to as "black carbon" pollution. The exhaust from burning fuels in automobiles, homes, and industries is a major source of pollution in the air. Some authorities believe that even the burning of wood and charcoal in fireplaces and barbeques can release significant quanitites of soot into the air.

Another type of pollution is the release of noxious gases, such as sulfur dioxide, carbon monoxide, nitrogen oxides, and chemical vapors. These can take part in further chemical reactions once they are in the atmosphere, forming smog and acid rain.

Pollution also needs to be considered inside our homes, offices, and schools. Some of these pollutants can be created by indoor activities such as smoking and cooking. In the United States, we spend about 80-90% of our time inside buildings, and so our exposure to harmful indoor pollutants can be serious. It is therefore important to consider both indoor andoutdoor air pollution.