Pollution

POLLUTIONEnvironmental Pollution

POLLUTIONIS WHEN SOMETHING IS ADDED TO THE

ENVIRONMENT THAT IS HARMFUL OR POISONOUS TO LIVING THINGS.

AN ECOLOGICAL VIEWPollution can be defined simply as the

accumulation of something where it is not wanted. This is a human-centered definition, based on human preferences and desires. The most basic reason for seeking to prohibit a particular place is that it has a harmful effect on people: it threatens their health or assaults their senses.

AN ECOLOGICAL VIEWEcology is the branch of science that is

concerned with the relationships of life-forms with each other and with their surroundings. The basic unit in ecology is ecosystem, a fairly self-contained system of plants and animals living in a particular kind of environment.

Example: A forest is an ecosystem; so is a lake.

WHAT IS A POLLUTANT?

POLLUTANT

Pollutant may be unwanted for a variety of reasons; in many cases, they can be desirable in one place and undesirable in another.

TWO BASIC FACTORS HAVE MADE POLLUTION AN ECOLOGICAL PROBLEM

Population and Technology –

There are more people on Earth than ever before, and many of them are using technology on unique scale. This combination of exploding population and galloping technology means that people are consuming tremendous amounts of energy and raw materials. Humans are also creating great quantities of waste, causing a worldwide ecological crisis.

WHAT NOW?An unsuccessful and certain aspect of

human history has been the destruction of the natural environment. No other living things have had such an impact on Earth. But by the same token, no other living things are capable of understanding their impact and acting in a forthright way to reserve it.

THE THREE TYPES OF POLLUTION:

1. Air Pollution2. Soil Pollution

3. Water Pollution

WATER POLLUTION

WATER POLLUTION

Water is the most precious natural resource on Earth, yet it is often the first resources to suffer from the effect of population growth and urban and industrial development. For centuries upon centuries, people have thought nothing of discarding their waste into the nearest body of water and letting the current or the tide carry it away.

SOURCES OF

WATER POLLUTION

SOURCES OF WATER POLLUTION

Today environmental scientists recognize two kinds of water pollution: point-source pollution, which is factory or sewage waste dumped directly into a waterway; and non point-source pollution, which is polluted runoff from such sources as agricultural fields, mines, landfills, streets, storm sewers, lawns, golf courses, and individual sewage systems

INDUSTRIAL POLLUTANTS(TOXIC CHEMICALS)

Among the most harmful of all human waste products are the chemical products and by-products of industrial processes. Chemical pollutants have been infiltrating the water supply for hundreds of years, but their volume, variety, and toxicity have been grown tremendously since the middle of the 20th century.


Acid Rain is an indirect form of chemical pollution that results from the interaction of the atmosphere with industrial pollutants such as oxides of sulfur and nitrogen formed in the combustion of fossil fuels, mainly by power plants. These pollutants change chemically and become acid aerosols that drift in the atmosphere for weeks, then combine with water and precipitate as dilute acid in rain and snow.


Toxic metals are unique because they neither created nor destroyed by industry and other human activities, but become a health risk when they are redistributed in ways that increase human exposure to them.


Hippocrates, the father of ancient Greek medicine, recognized that lead could be poisonous, but it has only been past few decades that efforts have been made to keep lead, mercury and other toxic metals out of water supplies. Lead is no longer used as an additive in gasoline or house paint, or as piping in water-supply systems. Use of mercury, once a common ingredient of many household products, is also carefully monitored.

CONTINUATION OF TOXIC METALS


Thermal pollution is a common waste product of many industries is heat. Electricity-generating plants, nuclear power plants, petroleum refineries, and many other manufacturing operations require enormous amounts of water to cool machinery that becomes very hot during normal operations. This water is usually drawn from a lake or river, then piped through the generating plant or factory, where it absorbs heat.


If it is discharged directly back into the lake or river at high temperatures, it can radically alter aquatic life. Plants and animals adapted to a specific temperature range and oxygen level may be unable to survive when the temperature increases a degree or too above the upper limit of that range. If even just one or two species disappear, the ecosystem may lack sufficient diversity to compensate for the loss.

CONTINUATION OF THERMAL POLLUTION

AIRPOLLUTION

AIR POLLUTION

Earth’s air, like its water and its soil, is often poisoned by the by-products of an expanding technological society. Air pollution is not a new problem. For as long as people have lived in close proximity to one another, they have polluted the air. What is new is the scope and severity of the problem.

CLASSIFYING:

AIR POLLUTION

CLASSIFYING: AIR POLLUTION

Many solid and liquid pollutants exist in the form of very small particles, or particulates, that are ligh enough to remain in the air for long periods of time. Solid particulates include dust, soot, and ash. Of increasing concern to health authorities are particles of metals, including lead and lead compounds, nickel and cadmium and beryllium. Liquid particles include mists and sprays.


The atmosphere contains a number of inorganic and organic gases that are pollutants. Inorganic gases include oxides of nitrogen, oxides of carbon, oxides of sulfur, and substances such as ammonia, chlorine, and hydrogen sulfide. Organic gases include hydrocarbons such as methane, benzene, acetylene, and ethylene; aldehydes and ketones; and compounds such as benzopyrene, alcohol and organic acids.


The most familiar air pollution is smoke, a mixture of particulates and gases released during the combustion of wood and other fuels. The term was fist used to describe a combination of smoke and fog, but now is applied to other types of visible air pollution.

The number and variety of air pollutants have increased steadily with the development of new chemicals. These chemicals, along with the waste products from industrial processes, enter the atmosphere in varying amounts.

SOURCES OF

AIR POLLUTION

SOURCES OF AIR POLLUTION

Most of the world’s major cities are afflicted with high levels of air pollution. This urban smog-produced by cars, incinerators, and power-generating plants-often drifts into many sub-urban and rural areas.

There is a chemical explanation for the color and toxicity of smog. Certain compounds that are present in automobile-exhaust emissions-gaseous hydrocarbons and oxides of nitrogen are invisible as they enter the atmosphere. Once in the air, however, they react under the influence of sunlight to form a dirty haze known as photochemical smog, a noxious form of pollution that in high levels brings tears to the eyes and makes people cough and choke as they breathe it.


Automobiles are a major source of urban air pollution in many other cities as well. Automobiles, buses, and trucks account for 60 percent of the air pollution, creating carbon monoxide (CO) levels in Mexico City far in excess of those in Los Angeles. Similarly, Sydney, Australia, long to believed to be among the last outposts of clean air, has a higher level of auto-mobile emissions in the atmosphere than does in any US city.


Trains, ships, and jet aircraft, also contribute substantial amounts of pollutants into the atmosphere. The long trail of black smoke left behind by a climbing jetliner is a pollutant similar, on a larger scale, to the exhaust cloud emitted by and automobile or truck. Some experts are especially alarmed by the large quantities of water and carbon dioxide that are added to the atmosphere by commercial aircraft flying at high altitudes.


Sadly, transportation is not the only source of serious air pollution. Industry and electricity-generating plants are major contributors as well. Other offenders include incineration of solid wastes, agricultural-burning, coal-waste fires, and forest fires.

EFFECTS OF

AIR POLLUTION

EFFECTS OF AIR POLLUTION

Human Health -

Air pollution has wide-ranging effects on most forms of life, and it poses serious and immediate physical dangers for human beings. It is difficult to assess the long term effects of air pollution on human health, although there is no doubt that emphysema, chronic bronchitis, bronchial asthma, and other respiratory are caused or aggravated by prolonged exposure to air pollution.


Effects on Plants -

Substances such as carbon monoxide, hydrocarbons, sulfur compounds, metals, acids and ozone are serious threats to most vegetation. Plants that absorb these pollutants may develop holes in their leaves, become discolored or wild, sometimes leading to death of the entire plant.


Effects on Buildings -

Air pollutants abrade, corrode, tarnish, soil, erode, crack, weaken, and discolor many human-made structures and materials. For example, sulfur dioxide pollution corrodes zinc, marble statues, and building stone, and accelerates the corrosion of steel by as much as for times. Ozone damages rubber and textiles, and discolors dyed materials. The settling of particulate matter necessitates frequent house painting and car washing.


Local Weather and Climate –

Wind and temperatures may also affect the quantity and extent of pollutants in the air. Strong air currents may disperse pollutants in both vertical and horizontal directions. Although this decreases pollutants in an industrial region, it may carry the undesirable particle to places far removed from the factories.


- Ozone Depletion- The atmosphere as a whole

SOILPOLLUTION

SOIL POLLUTION

Soil Pollution is the presence of toxic chemicals (pollutants or contaminants) in soil in high enough concentrations to be of risk to human health and/or ecosystem. Additionally, even when the levels of contaminants in soil are not of risk, soil pollution may occur simply due to the fact that the levels of the contaminants in soil exceed the levels that are naturally present in soil (in the case of contaminants which occur naturally in soil).

CAUSES OF

SOIL POLLUTION

SOIL POLLUTION

1. Antropogenic – through human activity including:

a. Accidental spills and leaks during storage, transport

or use of chemicals

(e.g.,leaks and spills of

gasoline and diesel at gas stations);

SOIL POLLUTION


b. Activities and Manufacturing Processes

that involve furnaces or other processes resulting in possible dispersion of contaminants in

environment; chemicals

SOIL POLLUTION


c. Mining activities involving crushing and

processing of raw materials

(such as mining activity);

SOIL POLLUTION


d. Construction activities

SOIL POLLUTION


e. Agricultural activities involving the spread of

herbicides/pesticides/insecticides and fertilizers;

SOIL POLLUTION


f. Transportaion Activities

SOIL POLLUTION


g. Dumping of chemicals (accidental or intended –

such as illegal dumping);

SOIL POLLUTION


h. Storage of wastes in landfills (which may leak to

groundwater or generate polluted vapors)

SOIL POLLUTION

2. Natural

a. Natural accumulation of compounds in soil

due to imbalances between atmospheric deposition and leaching

away with precipitation water (e.g., concentration and accumulation of

perchlorate in soils in arid

environments)

SOIL POLLUTION

2. Natural

b. Natural production in soil under certain environmental conditions

(e.g., natural formation of perchlorate in soil in the presence of a chlorine source,

metallic object and using the energy generated by a thunderstorm)

SOIL POLLUTION

2. Natural

c. Leaks from sewer lines into subsurface

(e.g., adding chlorine which could generate trihalometanes such as

chloroform).

SOIL POLLUTION

2. Natural

c. Leaks from sewer lines into subsurface

(e.g., adding chlorine which could generate trihalometanes such as

chloroform).

EFFECTS OF

SOIL POLLUTION

SOIL POLLUTION

1. Effect on Health of Humans:

Considering how soil is the reason we are able to sustain ourselves, the contamination of it has major consequences on our health. Crops and plants grown on polluted soil absorb much of the pollution and then pass these on to us. This could explain the sudden surge in small and terminal illnesses.

SOIL POLLUTION

2. Effect on Growth of Plants:

The ecological balance of any system gets affected due to the widespread contamination of the soil. Most plants are unable to adapt when the chemistry of the soil changes so radically in a short period of time. Fungi and bacteria found in the soil that bind it together begin to decline, which creates an additional problem of soil erosion.

SOIL POLLUTION

3. Decreased Soil Fertility:

The toxic chemicals present in the soil can decrease soil fertility and therefore decrease in the soil yield. The contaminated soil is then used to produce fruits and vegetables which lacks quality nutrients and may contain some poisonous substance to cause serious health problems in people consuming them.

SOIL POLLUTION

4. Toxic Dust:

The emission of toxic and foul gases from landfills pollutes the environment and causes serious effects on health of some people. The unpleasant smell causes inconvenience to other people.

SOIL POLLUTION

5. Changes in Soil Structure:

The death of many soil organisms in the soil can lead to alteration in soil structure. Apart from that, it could also force other predators to move to other places in search of food.

Date post:	14-Aug-2015
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Pollution

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