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Pollution

2007 Schools Wikipedia Selection. Related subjects: Environment

   Water pollution
   Enlarge
   Water pollution

   Pollution is the release of environmental contaminants. The U.S.,
   Russia, Mexico, China and Japan are the world leaders in air pollution
   emissions; however, Canada is the number two country on a per capita
   basis. The major forms of pollution include:
     * air pollution, the release of chemicals and particulates into the
       atmosphere. Common examples include carbon monoxide, sulfur
       dioxide, chlorofluorocarbons (CFCs), and nitrogen oxides produced
       by industry and motor vehicles. Ozone and smog are created as
       nitrogen oxides and hydrocarbons react to sunlight.
     * water pollution via surface runoff and leaching to groundwater.
     * Soil contamination occurs when chemicals are released by spill or
       underground storage tank leakage. Among the most significant soil
       contaminants are hydrocarbons, heavy metals, MTBE, herbicides,
       pesticides and chlorinated hydrocarbons.
     * radioactive contamination, added in the wake of 20th-century
       discoveries in atomic physics. (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 junk or municipal solid waste.

Effects on human health

   Pollutants can cause disease, including cancer, lupus, immune diseases,
   allergies, and asthma. Higher levels of background radiation have led
   to an increased incidence of cancer and mortality associated with it
   worldwide. Some illnesses are named for the places where specific
   pollutants were first formally implicated. One example is Minamata
   disease, which is caused by organic mercury compounds.

   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. Oil spills
   can cause skin irritations and rashes. Noise pollution induces hearing
   loss, high blood pressure, stress and sleep disturbance.

Regulation and monitoring

United States

   The United States Environmental Protection Agency (EPA) established
   threshold standards for air pollutants to protect human health on
   January 1, 1970. One of the ratings chemicals are given is
   carcinogenicity. In addition to the classification "unknown",
   designated levels range from non-carcinogen, to likely and known
   carcinogen. But some scientists have said that the concentrations which
   most of these levels indicate are far too high and the exposure of
   people should be less. In 1999, the United States EPA replaced the
   Pollution Standards Index (PSI) with the Air Quality Index (AQI) to
   incorporate new PM2.5 and Ozone standards.

   Passage of the Clean Water Act amendments of 1977 required strict
   permitting for any contaminant discharge to navigable waters, and also
   required use of best management practices for a wide range of other
   water discharges including thermal pollution.

   Passage of the Noise Control Act established mechanisms of setting
   emission standards for virtually every source of noise including motor
   vehicles, aircraft, certain types of HVAC equipment and major
   appliances. It also put local government on notice as to their
   responsibilities in land use planning to address noise mitigation. This
   noise regulation framework comprised a broad data base detailing the
   extent of noise health effects.

   The U.S. has a maximum fine of US$25,000 for dumping toxic waste.
   However, many large manufacturers decline to dispute violations, as
   they can easily afford this small fine. The state of California Cal/EPA
   Office of Environmental Health Hazard Assessment (OEHHA) has maintained
   an independent list of substances with product labeling requirements as
   part of Proposition 65 since 1986.

Europe

   We can notice pollution on this french building, in Bordeaux
   Enlarge
   We can notice pollution on this french building, in Bordeaux

   Generally the European countries lagged significantly behind the United
   States in meaningful environmental regulation, including air quality
   standards, water quality standards, soil contamination cleanup, indoor
   air quality and noise regulations. Despite this, European pollution
   output is far lower than that of the USA. In the year 2000, UK Air
   Quality Regulations were established and they were further amended in
   2002. There has also been British harmonization with EU regulations.

   The EU is presently entertaining use of the carcinogen MTBE as a
   widespread gasoline additive, a chemical which has been in the process
   of phaseout in the U.S. for over a decade.

The United Kingdom

   In the United Kingdom, it took until the 1840s to bring onto the
   statute books legislation to control water pollution. It was extended
   to all rivers and coastal water by 1961. However, currently the clean
   up of historic contamination is controlled under a specific statutory
   scheme found in Part IIA of the Environmental Protection Act 1990 (Part
   IIA), as inserted by the Environment Act 1995, and other ‘rules’ found
   in regulations and statutory guidance. The Act came into force in
   England in April 2000.

Pollution of controlled waters

   The second part of the statutory definition of contaminated land covers
   where polluting material is entering or likely to enter controlled
   waters. The statutory guidance provides that the likelihood of the
   entry of the contaminant is to be assessed on the balance of
   probabilities. The definition of contaminated land within Part IIA (in
   relation to pollution of controlled waters), in that the contamination
   will need to be deemed to be significant.

   There is currently no guidance available on what may, or may not, be
   significant pollution of controlled waters except that one that is
   based upon risk is considered to be appropriate. This approach has
   already been taking place throughout the industry and widely accepted
   by the regulators as a means of assessing the significance of
   groundwater contamination. As such pollutant linkages with respect to
   ground and surface water targets/receptors are considered in a similar
   manner to that for significant harm.

Soil contamination

   Two sources of published generic guidance are currently commonly used
   in the UK:
     * The Contaminated Land Exposure Assessment (CLEA) Guidelines
     * The Dutch Standards.

   Guidance by the Inter Departmental Committee for the Redevelopment of
   Contaminated Land (ICRCL) has been formally withdrawn by the Department
   for Environment, Food and Rural Affairs (DEFRA), for use as a
   prescriptive document to determine the potential need for remediation
   or further assessment. Therefore, no further reference is made to these
   former guideline values.

   Other generic guidance that may be referred to (to put the
   concentration of a particular contaminant in context), include the
   United States EPA Region 9 Preliminary Remediation Goals (US PRGs), the
   US EPA Region 3 Risk Based Concentrations (US EPA RBCs) and National
   Environment Protection Council of Australia Guideline on Investigation
   Levels in Soil and Groundwater.

   The CLEA model published by DEFRA and the Environment Agency (EA) in
   March 2002 sets a framework for the appropriate assessment of risks to
   human health from contaminated land, as required by Part IIA of the
   Environmental Protection Act 1990. As part of this framework, generic
   Soil Guideline Values (SGVs) have currently been derived for ten
   contaminants to be used as “intervention values”. These values should
   not be considered as remedial targets but values above which further
   detailed assessment should be considered.

   Three sets of CLEA SGVs have been produced for three different land
   uses, namely:
     * residential (with and without plant uptake)
     * allotments
     * commercial/industrial

   It is intended that the SGVs replace the former ICRCL values. It should
   be noted that the CLEA SGVs relate to assessing chronic (long term)
   risks to human health and do not apply to the protection of ground
   workers during construction, or other potential receptors such as
   groundwater, buildings, plants or other ecosystems. The CLEA SGVs are
   not directly applicable to a site completely covered in hardstanding,
   as there is no direct exposure route to contaminated soils.

   To date, the first ten of fifty-five contaminant SGVs have been
   published, for the following: arsenic, cadmium, chromium, lead,
   inorganic mercury, nickel, selenium ethyl benzene, phenol and toluene.
   Draft SGVs for benzene, naphthalene and xylene have been produced but
   their publication is on hold. Toxicological data (Tox) has been
   published for each of these contaminants as well as for benzo[a]pyrene,
   benzene, dioxins, furans and dioxin-like PCBs, naphthalene, vinyl
   chloride, 1,1,2,2 tetrachloroethane and 1,1,1,2 tetrachloroethane,
   1,1,1 trichloroethane, tetrachloroethene, carbon tetrachloride,
   1,2-dichloroethane, trichloroethene and xylene. The SGVs for ethyl
   benzene, phenol and toluene are dependent on the soil organic matter
   (SOM) content (which can be calculated from the total organic carbon
   (TOC) content). As an initial screen the SGVs for 1% SOM are considered
   to be appropriate.

Groundwater

   The Water Supply Regulations (WSR) 1989 value, the UK Freshwater
   Environmental Quality Standards (FEQS), Dutch Intervention Values
   (DIV), World Health Organisation (WHO) Guidelines for Drinking Water
   Quality 2004 and USEPA Drinking Water Advisory are used in the UK as
   initial conservative screening values to assess whether groundwater
   contamination requires further assessment in terms of the wider
   groundwater/surface water environment. Where further assessment is
   considered necessary, this is undertaken qualitatively or
   quantitatively (if considered necessary or appropriate)on a Site
   specific basis using the Environment Agency (EA) Spreadsheets
   associated with R & D Paper 20, “Methodology for the Derivation of
   Remedial Targets for Soil and Groundwater to Protect Water Resources,
   Version 2.2” or similar.

China

   China's rapid industrialization has substantially increased pollution.
   China has some relevant regulations: the 1979 Environmental Protection
   Law, which was largely modelled on U.S. legislation. But the
   environment continues to deteriorate. Twelve years after the law, only
   one Chinese city was making an effort to clean up its water discharges.
   This indicates that China is about 30 years behind the U.S. schedule of
   environmental regulation and 10 to 20 years behind Europe.

International

   The Kyoto Protocol is an amendment to the United Nations Framework
   Convention on Climate Change (UNFCCC), an international treaty on
   global warming. It also reaffirms sections of the UNFCCC. Countries
   which ratify this protocol commit to reduce their emissions of carbon
   dioxide and five other greenhouse gases, or engage in emissions trading
   if they maintain or increase emissions of these gases. A total of 141
   countries have ratified the agreement. Notable exceptions include the
   United States and Australia, who have signed but not ratified the
   agreement. The stated reason for the United States not ratifying is the
   exemption of large emitters of greenhouse gases who are also developing
   countries, like China and India.

History

Prehistory

   Humankind has had some effect upon the natural environment since the
   paleolithic era during which the ability to generate fire was acquired.
   In the iron age, the use of tooling led to the practice of metal
   grinding on a small scale and resulted in minor accumulations of
   discarded material probably easily dispersed without too much impact.
   Human wastes would have polluted rivers or water sources to some
   degree. However, these effects could be expected predominantly to be
   dwarfed by the natural world.

Ancient cultures

   The first advanced civilizations of China, Egypt, Persia, Greece and
   Rome increased the use of water for primitive industrial processes,
   increasingly forged metal and created fires of wood and peat for more
   elaborate purposes (for example, bathing, heating). Still, at this time
   the scale of higher activity did not disrupt ecosystems or greatly
   alter air or water quality.

Middle Ages

   The dark ages and early Middle Ages were a great boon for the
   environment, in that industrial activity fell, and population levels
   did not grow rapidly. Toward the end of the Middle Ages populations
   grew and concentrated more within cities, creating pockets of readily
   evident contamination. In certain places air pollution levels were
   recognizable as health issues, and water pollution in population
   centers was a serious medium for disease transmission from untreated
   human waste.

   Since travel and widespread information were less common, there did not
   exist a more general context than that of local consequences in which
   to consider pollution. Foul air would have been considered a nuissance
   and wood, or eventually, coal burning produced smoke, which in
   sufficient concentrations could be a health hazard in proximity to
   living quarters. Septic contamination or poisoning of a clean drinking
   water source was very easily fatal to those who depended on it,
   especially if such a resource was rare. Superstitions predominated and
   the extent of such concerns would probably have been little more than a
   sense of moderation and an avoidance of obvious extremes.

First recognition

   But gradually increasing populations and the proliferation of basic
   industrial processes saw the emergence of a civilization that began to
   have a much greater collective impact on its surroundings. It was to be
   expected that the beginnings of environmental awareness would occur in
   the more developed cultures, particularly in the densest urban centers.
   The first medium warranting official policy measures in the emerging
   western world would be the most basic: the air we breathe.

   King Edward I of England banned the burning of sea-coal by proclamation
   in London in 1272, after its smoke had become a problem. 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 there,
   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.

Modern awareness

   Early Soviet poster, before the modern awareness: "The smoke of
   chimneys is the breath of Soviet Russia"
   Enlarge
   Early Soviet poster, before the modern awareness: "The smoke of
   chimneys is the breath of Soviet Russia"

   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, such as Erin Brockovich, 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 " 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. 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 industrial
   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 the 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, have been detected in various
   ecological habitats far removed from industrial activity such as the
   arctic, demonstrating 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.

Perspectives

   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 mankind, 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
   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. 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.

Controversy

   Industry and concerned citizens have battled for decades over the
   significance of various forms of pollution. Salient parameters of these
   disputes are whether:
     * a given pollutant affects all people or simply a genetically
       vulnerable set.
     * an effect is only specific to certain species.
     * whether the effect is simple, or whether it causes linked secondary
       and tertiary effects, especially on biodiversity
     * an effect will only be apparent in the future and is presently
       negligible.
     * the threshold for harm is present.
     * the pollutant is of direct harm or is a precursor.
     * employment or economic prosperity will suffer if the pollutant is
       abated.

   Blooms of algae and the resultant eutrophication of lakes and coastal
   ocean is considered pollution when it is caused by nutrients from
   industrial, agricultural, or residential runoff in either point source
   or nonpoint source form (see the article on eutrophication for more
   information).

   Heavy metals such as lead and mercury have a role in geochemical cycles
   and they occur naturally. These metals may also be mined and, depending
   on their processing, may be released disruptively in large
   concentrations into an environment they had previously been absent
   from. Just as the effect of anthropogenic release of these metals into
   the environment may be considered 'polluting', similar environmental
   impacts could also occur in some areas due to either autochthonous or
   historically 'natural' geochemical activity.
   Historical and projected CO2 emissions by country (1990-2025). Source:
   Energy Information Administration.
   Enlarge
   Historical and projected CO2 emissions by country (1990-2025).
   Source: Energy Information Administration.

   Carbon dioxide, while vital for photosynthesis, is sometimes referred
   to as pollution, because raised levels of the gas in the atmosphere
   affect the Earth's climate. See global warming for an extensive
   discussion of this topic. 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.

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