Hello again everybody,how are you?I hope all of you are healthy and excited to read my blog..(I hope so)haha,what we want to learn in this time..do you know about pollution??I know some of you know about pollution..Let me add your information about pollution..Just read and I hope you understand..
Pollution is the introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the
ecosystem i.e. physical systems or living organisms .
[1] Pollution can take the form of
chemical substances, or
energy, such as noise, heat, or light. Pollutants, the elements of pollution, can be foreign substances or energies, or naturally occurring; when naturally occurring, they are considered contaminants when they exceed natural levels. Pollution is often classed as
point source or
nonpoint source pollution. The
Blacksmith Institute issues annually a list of the world's worst polluted places. In the 2007 issues the ten top nominees are located in
Azerbaijan,
China,
India,
Peru,
Russia,
Ukraine and
Zambia.
Contents[
show]
1 Ancient cultures2 Official acknowledgement3 Modern awareness4 Forms of pollution5 Pollutants6 Sources and causes7 Effects7.1 Human health7.2 Environment8 Regulation and monitoring9 Pollution control9.1 Pollution control devices10 Perspectives11 Greenhouse gases and global warming12 See also13 References14 External linksAncient cultures
The forging of metals appears to be a key turning point in the creation of significant air pollution levels. Core samples of glaciers in Greenland indicate increases in air pollution associated with Greek, Roman and Chinese metal production
[2].
Official acknowledgement
The earliest known writings concerned with pollution were
Arabic medical treatises written between the 9th and 13th centuries, by physicians such as
al-Kindi (Alkindus),
Qusta ibn Luqa (Costa ben Luca),
Muhammad ibn Zakarīya Rāzi (Rhazes),
Ibn Al-Jazzar,
al-Tamimi,
al-Masihi,
Ibn Sina (Avicenna),
Ali ibn Ridwan, Ibn Jumay,
Isaac Israeli ben Solomon,
Abd-el-latif, Ibn al-Quff, and
Ibn al-Nafis. Their works covered a number of subjects related to pollution such as
air contamination,
water contamination,
soil contamination,
solid waste mishandling, and
environmental assessments of certain localities.
[3]King Edward I of
England banned the burning of
sea-coal by proclamation in
London in 1272, after its smoke had become a problem.
[4][5] But the fuel was so common in England that this earliest of names for it was acquired because it could be carted away from some shores by the wheelbarrow. Air pollution would continue to be a problem in England, especially later during the industrial revolution, and extending into the recent past with the
Great Smog of 1952. This same city also recorded one of the earlier extreme cases of water quality problems with the
Great Stink on the
Thames of 1858, which led to construction of the
London sewerage system soon afterward.
It was the
industrial revolution that gave birth to environmental pollution as we know it today. The emergence of great factories and consumption of immense quantities of
coal and other
fossil fuels gave rise to unprecedented
air pollution and the large volume of industrial
chemical discharges added to the growing load of untreated human waste.
Chicago and
Cincinnati were the first two American cities to enact laws ensuring cleaner air in 1881. Other cities followed around the country until early in the 20th century, when the short lived Office of Air Pollution was created under the Department of the Interior. Extreme smog events were experienced by the cities of
Los Angeles and
Donora, Pennsylvania in the late 1940s, serving as another public reminder.
[6]Modern awareness
Early Soviet poster, before the modern awareness: "The smoke of chimneys is the breath of Soviet Russia"
Pollution became a popular issue after WW2, when the aftermath of atomic warfare and testing made evident the perils of radioactive fallout. Then a conventional catastrophic event The
Great Smog of 1952 in London killed at least 8000 people. This massive event prompted some of the first major modern environmental legislation, The
Clean Air Act of 1956.
Pollution began to draw major public attention in the United States between the mid-1950s and early 1970s, when Congress passed the
Noise Control Act, the
Clean Air Act, the
Clean Water Act and the
National Environmental Policy Act.
Bad bouts of local pollution helped increase consciousness.
PCB dumping in the
Hudson River resulted in a ban by the
EPA on consumption of its fish in 1974. Long-term
dioxin contamination at
Love Canal starting in 1947 became a national news story in 1978 and led to the
Superfund legislation of 1980. Legal proceedings in the 1990s helped bring to light
Chromium-6 releases in
California--the champions of whose victims became famous. The pollution of industrial land gave rise to the name
brownfield, a term now common in
city planning.
DDT was banned in most of the developed world after the publication of Rachel Carson's
Silent Spring.
The development of nuclear science introduced
radioactive contamination, which can remain lethally radioactive for hundreds of thousands of years.
Lake Karachay, named by the
Worldwatch Institute as the "most polluted spot" on earth, served as a disposal site for the Soviet Union thoroughout the 1950s and 1960s. Second place may go to the to the area of Chelyabinsk U.S.S.R. (see reference below) as the "Most polluted place on the planet".
Nuclear weapons continued to be tested in the
Cold War, sometimes near inhabited areas, especially in the earlier stages of their development. The toll on the worst-affected populations and the growth since then in understanding about the critical threat to human health posed by
radioactivity has also been a prohibitive complication associated with
nuclear power. Though extreme care is practiced in that industry, the potential for disaster suggested by incidents such as those at
Three Mile Island and
Chernobyl pose a lingering specter of public mistrust. One legacy of
nuclear testing before
most forms were banned has been significantly raised levels of
background radiation.
International catastrophes such as the wreck of the
Amoco Cadiz oil tanker off the coast of
Brittany in 1978 and the
Bhopal disaster in 1984 have demonstrated the universality of such events and the scale on which efforts to address them needed to engage. The borderless nature of atmosphere and oceans inevitably resulted in the implication of pollution on a planetary level with the issue of global warming. Most recently the term
persistent organic pollutant (POP) has come to describe a group of chemicals such as
PBDEs and
PFCs among others. Though their effects remain somewhat less well understood owing to a lack of experimental data, they have been detected in various ecological habitats far removed from industrial activity such as the Arctic, demonstrating diffusion and bioaccumulation after only a relatively brief period of widespread use.
Growing evidence of local and global pollution and an increasingly informed public over time have given rise to
environmentalism and the
environmental movement, which generally seek to limit human impact on the environment.
Forms of pollution
The major forms of pollution are listed below along with the particular pollutants relevant to each of them:
Air pollution, the release of chemicals and particulates into the atmosphere. Common gaseous air pollutants include
carbon monoxide,
sulfur dioxide,
chlorofluorocarbons (CFCs) and
nitrogen oxides produced by
industry and motor vehicles. Photochemical
ozone and
smog are created as nitrogen oxides and
hydrocarbons react to sunlight.
Particulate matter, or fine dust is characterized by their
micrometre size PM10 to PM2.5.
Water pollution, by the release of waste products and contaminants into surface
runoff into river drainage systems, leaching into
groundwater, liquid spills,
wastewater discharges,
eutrophication and littering.
Soil contamination occurs when chemicals are released by spill or underground leakage. Among the most significant
soil contaminants are
hydrocarbons,
heavy metals,
MTBE[7],
herbicides,
pesticides and
chlorinated hydrocarbons.
LitteringRadioactive contamination, resulting from 20th century activities in
atomic physics, such as nuclear power generation and nuclear weapons research, manufacture and deployment. (See
alpha emitters and
actinides in the environment.)
Noise pollution, which encompasses
roadway noise,
aircraft noise,
industrial noise as well as high-intensity
sonar.
Light pollution, includes light trespass,
over-illumination and
astronomical interference.
Visual pollution, which can refer to the presence of overhead
power lines, motorway
billboards, scarred
landforms (as from
strip mining), open storage of trash or
municipal solid waste.
Thermal pollution, is a
temperature change in natural water bodies caused by human influence, such as use of water as coolant in a power plant.
Pollutants
Main article:
PollutantA pollutant is a waste material that pollutes air, water or soil. Three factors determine the severity of a pollutant: its chemical nature, the concentration and the persistence
Sources and causes
Air pollution comes from both natural and man made sources. Though globally man made pollutants from combustion, construction, mining, agriculture and warfare are increasingly significant in the air pollution equation.
[8]Motor vehicle emissions are one of the leading causes of air pollution.
[9][10][11] China,
United States,
Russia,
Mexico, and
Japan are the world leaders in air pollution emissions. Principal stationary pollution sources include
chemical plants, coal-fired
power plants,
oil refineries,
[12] petrochemical plants,
nuclear waste disposal activity, incinerators, large livestock farms (dairy cows, pigs, poultry, etc.),
PVC factories, metals production factories, plastics factories, and other heavy industry. Agricultural air pollution comes from contemporary practices which include clear felling and burning of natural vegetation as well as spraying of pesticides and herbicides
[13]About 400 million metric tons of
hazardous wastes are generated each year.
[14] The
United States alone produces about 250 million metric tons.
[15] Americans constitute less than 5% of the
world's population, but produce roughly 25% of the world’s
CO2,
[16] and generate approximately 30% of
world’s waste.
[17][18] In 2007,
China has overtaken the United States as the world's biggest producer of CO2.
[19]In February 2007, a report by the Intergovernmental Panel on Climate Change (IPCC), representing the work of 2,500 scientists from more than 130 countries, said that humans have been the primary cause of global warming since 1950. Humans have ways to cut greenhouse gas emissions and avoid the consequences of global warming, a major climate report concluded. But in order to change the climate, the transition from fossil fuels like coal and oil needs to occur within decades, according to the final report this year from the UN's Intergovernmental Panel on Climate Change (IPCC)
[20].
Some of the more common
soil contaminants are
chlorinated hydrocarbons (CFH),
heavy metals (such as
chromium,
cadmium--found in rechargeable
batteries, and
lead--found in lead
paint,
aviation fuel and still in some countries,
gasoline),
MTBE,
zinc,
arsenic and
benzene. In 2001 a series of press reports culminating in a book called
Fateful Harvest unveiled a widespread practice of recycling industrial byproducts into fertilizer, resulting in the contamination of the soil with various metals. Ordinary municipal
landfills are the source of many chemical substances entering the soil environment (and often groundwater), emanating from the wide variety of refuse accepted, especially substances illegally discarded there, or from pre-1970 landfills that may have been subject to little control in the U.S. or EU. There have also been some unusual releases of
polychlorinated dibenzodioxins, commonly called dioxins for simplicity, such as
TCDD.
[21]Pollution can also be the consequence of a natural disaster. For example,
hurricanes often involve water contamination from sewage, and
petrochemical spills from ruptured
boats or
automobiles. Larger scale and environmental damage is not uncommon when coastal
oil rigs or
refineries are involved. Some sources of pollution, such as
nuclear power plants or
oil tankers, can produce widespread and potentially hazardous releases when accidents occur.
In the case of
noise pollution the dominant source class is the
motor vehicle, producing about ninety percent of all unwanted noise worldwide.
Effects
Human health
Overview of main health effects on humans from some common types of pollution.
[22] [23] [24]Adverse
air quality can kill many organisms including humans. Ozone pollution can cause
respiratory disease,
cardiovascular disease,
throat inflammation, chest pain, and congestion. Water pollution causes approximately 14,000 deaths per day, mostly due to contamination of
drinking water by untreated
sewage in
developing countries. An estimated 700 million
Indians have no access to a proper toilet, and 1,000 Indian children die of diarrhoeal sickness every day.
[25] Nearly 500 million Chinese lack access to safe drinking water.
[26] 656,000 people die prematurely each year in
China because of air pollution. In
India, air pollution is believed to cause 527,700 fatalities a year.
[27] Studies have estimated that the number of people killed annually in the US could be over 50,000.
[28]Oil spills can cause
skin irritations and rashes. Noise pollution induces
hearing loss,
high blood pressure,
stress, and
sleep disturbance.
Mercury has been linked to
developmental deficits in children and
neurologic symptoms. Older people are majorly exposed to diseases induced by air pollution. Those with heart or lung disorders are under additional risk. Children and infants are also at serious risk.
Lead and other
heavy metals have been shown to cause neurological problems. Chemical and
radioactive substances can
cause cancer and
as well as birth defects.
Environment
Pollution has been found to be present widely in the
environment. There are a number of effects of this:
Sulphur dioxide and
nitrogen oxides can cause
acid rain which lowers the
pH value of soil.
Nitrogen oxides are removed from the air by rain and
fertilise land which can change the species composition of ecosystems.
Soil can become infertile and unsuitable for plants. This will affect other
organisms in the
food web.
Smog and haze can reduce the amount of sunlight received by plants to carry out
photosynthesis and leads to the production of
tropospheric ozone which damages plants.
Invasive species can out compete native species and reduce
biodiversity. Invasive plants can contribute debris and biomolecules (
allelopathy) that can alter soil and chemical compositions of an environment, often reducing native species
competitiveness.
Biomagnification describes situations where toxins (such as
heavy metals) may pass through trophic levels, becoming exponentially more concentrated in the process.
Carbon dioxide emissions cause
ocean acidification, the ongoing decrease in the pH of the Earth's oceans as CO2 becomes dissolved.
The emission of
greenhouse gases leads to
global warming which affects ecosystems in many ways.
Regulation and monitoring
Main article:
Regulation and monitoring of pollutionTo protect the environment from the adverse effects of pollution, many nations worldwide have enacted legislation to regulate various types of pollution as well as to mitigate the adverse effects of pollution.
Pollution control
Pollution control is a term used in
environmental management. It means the control of
emissions and
effluents into air, water or soil. Without pollution control, the waste products from consumption, heating, agriculture, mining, manufacturing, transportation and other human activities, whether they accumulate or disperse, will degrade the
environment. In the hierarchy of controls,
pollution prevention and
waste minimization are more desirable than pollution control.
Pollution control devices
Dust collection systemsCyclonesElectrostatic precipitatorsBaghousesScrubbersBaffle spray scrubberCyclonic spray scrubberEjector venturi scrubberMechanically aided scrubberSpray towerWet scrubberSewage treatmentAPI oil-water separators[29][12]Sedimentation (water treatment)Dissolved air flotation (DAF)
Activated sludge biotreatersBiofiltersPowdered activated carbon treatmentVapor recovery systemsPerspectives
The earliest precursor of pollution generated by life forms would have been a natural function of their existence. The attendant consequences on viability and population levels fell within the sphere of
natural selection. These would have included the demise of a population locally or ultimately, species extinction. Processes that were untenable would have resulted in a new balance brought about by changes and adaptations. At the extremes, for any form of life, consideration of pollution is superseded by that of survival.
For humankind, the factor of technology is a distinguishing and critical consideration, both as an enabler and an additional source of byproducts. Short of survival, human concerns include the range from quality of life to health hazards. Since science holds experimental demonstration to be definitive, modern treatment of toxicity or environmental harm involves defining a level at which an effect is observable. Common examples of fields where practical measurement is crucial include
automobile emissions control, industrial exposure (eg
Occupational Safety and Health Administration (OSHA)
PELs),
toxicology (eg
LD50), and
medicine (eg
medication and
radiation doses).
"The solution to pollution is dilution", is a dictum which summarizes a traditional approach to pollution management whereby sufficiently diluted pollution is not harmful.
[30][31] It is well-suited to some other modern, locally-scoped applications such as laboratory safety procedure and
hazardous material release emergency management. But it assumes that the dilutant is in virtually unlimited supply for the application or that resulting dilutions are acceptable in all cases.
Such simple treatment for environmental pollution on a wider scale might have had greater merit in earlier centuries when physical survival was often the highest imperative, human population and densities were lower, technologies were simpler and their byproducts more benign. But these are often no longer the case. Furthermore, advances have enabled measurement of concentrations not possible before. The use of statistical methods in evaluating outcomes has given currency to the principle of probable harm in cases where assessment is warranted but resorting to deterministic models is impractical or unfeasible. In addition, consideration of the environment beyond direct impact on human beings has gained prominence.
Yet in the absence of a superseding principle, this older approach predominates practices throughout the world. It is the basis by which to gauge concentrations of effluent for legal release, exceeding which penalties are assessed or restrictions applied. The regressive cases are those where a controlled level of release is too high or, if enforceable, is neglected. Migration from pollution dilution to elimination in many cases is confronted by challenging economical and technological barriers.
Greenhouse gases and global warming
Main article:
Global warmingHistorical and projected CO2 emissions by country.Source: Energy Information Administration.
[32][33]Carbon dioxide, while vital for
photosynthesis, is sometimes referred to as pollution, because raised levels of the gas in the atmosphere are affecting the Earth's climate. Disruption of the environment can also highlight the connection between areas of pollution that would normally be classified separately, such as those of water and air. Recent studies have investigated the potential for long-term rising levels of atmospheric carbon dioxide to cause slight but critical
increases in the acidity of ocean waters, and the possible effects of this on marine ecosystems.
