Pollution is the introduction of
contaminant
Contamination is the presence of a constituent, impurity, or some other undesirable element that renders something unsuitable, unfit or harmful for the physical body, natural environment, wiktionary:Workplace, workplace, etc.
Types of contamina ...
s into the
natural environment
The natural environment or natural world encompasses all life, biotic and abiotic component, abiotic things occurring nature, naturally, meaning in this case not artificiality, artificial. The term is most often applied to Earth or some parts ...
that cause harm. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light).
Pollutant
A pollutant or novel entity is a substance or energy introduced into the environment that has undesired effect, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like oi ...
s, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants.
Although environmental pollution can be caused by natural events, the word pollution generally implies that the contaminants
have a human source, such as
manufacturing
Manufacturing is the creation or production of goods with the help of equipment, labor, machines, tools, and chemical or biological processing or formulation. It is the essence of the
secondary sector of the economy. The term may refer ...
,
extractive industries, poor
waste management
Waste management or waste disposal includes the processes and actions required to manage waste from its inception to its final disposal. This includes the collection, transport, treatment, and disposal of waste, together with monitor ...
, transportation or
agriculture
Agriculture encompasses crop and livestock production, aquaculture, and forestry for food and non-food products. Agriculture was a key factor in the rise of sedentary human civilization, whereby farming of domesticated species created ...
. Pollution is often classed as
point source
A point source is a single identifiable ''localized'' source of something. A point source has a negligible extent, distinguishing it from other source geometries. Sources are called point sources because, in mathematical modeling, these sources ...
(coming from a highly concentrated specific site, such as a
factory
A factory, manufacturing plant or production plant is an industrial facility, often a complex consisting of several buildings filled with machinery, where workers manufacture items or operate machines which process each item into another. Th ...
,
mine,
construction site
Construction are processes involved in delivering buildings, infrastructure, industrial facilities, and associated activities through to the end of their life. It typically starts with planning, financing, and design that continues until the a ...
), or
nonpoint source pollution
Nonpoint source (NPS) pollution refers to diffuse contamination (or pollution) of water or air that does not originate from a single discrete source. This type of pollution is often the cumulative effect of small amounts of contaminants gathered ...
(coming from a widespread distributed sources, such as
microplastics
Microplastics are "synthetic solid particles or polymeric matrices, with regular or irregular shape and with size ranging from 1 μm to 5 mm, of either primary or secondary manufacturing origin, which are insoluble in water." Microplastics a ...
or
agricultural runoff).
Many sources of pollution were unregulated parts of
industrialization
Industrialisation (British English, UK) American and British English spelling differences, or industrialization (American English, US) is the period of social and economic change that transforms a human group from an agrarian society into an i ...
during the 19th and 20th centuries until the emergence of environmental
regulation
Regulation is the management of complex systems according to a set of rules and trends. In systems theory, these types of rules exist in various fields of biology and society, but the term has slightly different meanings according to context. Fo ...
and pollution
policy
Policy is a deliberate system of guidelines to guide decisions and achieve rational outcomes. A policy is a statement of intent and is implemented as a procedure or protocol. Policies are generally adopted by a governance body within an or ...
in the later half of the 20th century. Sites where historically polluting industries released
persistent pollutants may have
legacy pollution
Legacy pollution or legacy pollutants are persistent materials in the environment that were created through a polluting industry or process that have polluting effects after the process has finished. Frequently these include persistent organic p ...
long after the source of the pollution is stopped. Major forms of pollution include
air pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
,
water pollution
Water pollution (or aquatic pollution) is the contamination of Body of water, water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and ...
,
litter
Litter consists of waste products that have been discarded incorrectly, without consent, at an unsuitable location. The waste is objects, often man-made, such as aluminum cans, paper cups, food wrappers, cardboard boxes or plastic bottles, but ...
,
noise pollution
Noise pollution, or sound pollution, is the propagation of noise or sound with potential harmful effects on humans and animals. The source of outdoor noise worldwide is mainly caused by machines, transport and propagation systems.Senate Publi ...
,
plastic pollution
Plastic pollution is the accumulation of plastic objects and particles (e.g. plastic bottles, bags and microbeads) in the Earth's environment that adversely affects humans, wildlife and their habitat. Plastics that act as pollutants are catego ...
,
soil contamination
Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activit ...
,
radioactive contamination
Radioactive contamination, also called radiological pollution, is the deposition of, or presence of Radioactive decay, radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is uni ...
,
thermal pollution
Thermal pollution, sometimes called "thermal enrichment", is the degradation of water quality by any process that changes ambient water temperature. Thermal pollution is the rise or drop in the temperature of a natural body of water caused by h ...
,
light pollution
Light pollution is the presence of any unwanted, inappropriate, or excessive artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting sources, during the ...
, and
visual pollution
The visual system is the physiological basis of visual perception (the ability to detect and process light). The system detects, transduces and interprets information concerning light within the visible range to construct an image and buil ...
.
Pollution has widespread consequences on human and
environmental health
Environmental health is the branch of public health concerned with all aspects of the natural environment, natural and built environment affecting human health. To effectively control factors that may affect health, the requirements for a hea ...
, having systematic impact on social and economic systems. In 2019, pollution killed approximately nine million people worldwide (about one in six deaths that year); about three-quarters of these deaths were caused by
air pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
.
A 2022 literature review found that levels of anthropogenic chemical pollution have exceeded
planetary boundaries
Planetary boundaries are a framework to describe limits to the impacts of human activities on the Earth system. Beyond these limits, the environment may not be able to continue to self-regulate. This would mean the Earth system would leave th ...
and now threaten entire ecosystems around the world.
Pollutants frequently have outsized impacts on vulnerable populations, such as children and the elderly, and marginalized communities, because polluting industries and toxic waste sites tend to be collocated with populations with less economic and political power. This outsized impact is a core reason for the formation of the
environmental justice movement
Environmental justice is a social movement that addresses injustice that occurs when poor or marginalized communities are harmed by hazardous waste, resource extraction, and other land uses from which they do not benefit. The movement has gene ...
,
[Schlosberg, David. (2007) ''Defining Environmental Justice: Theories, Movements, and Nature''. Oxford University Press.] and continues to be a core element of
environmental conflict
Environmental conflicts, socio-environmental conflict or ecological distribution conflicts (EDCs) are social conflicts caused by environmental degradation or by Environmental justice, unequal distribution of environmental resources. The Environm ...
s, particularly in the
Global South
Global North and Global South are terms that denote a method of grouping countries based on their defining characteristics with regard to socioeconomics and politics. According to UN Trade and Development (UNCTAD), the Global South broadly com ...
.
Because of the impacts of these chemicals, local and international countries' policy have increasingly sought to regulate pollutants, resulting in increasing air and water quality standards, alongside regulation of specific waste streams. Regional and national policy is typically supervised by
environmental agencies or ministries, while international efforts are coordinated by the
UN Environmental Program and other
treaty bodies. Pollution
mitigation
Mitigation is the reduction of something harmful that has occurred or the reduction of its harmful effects. It may refer to measures taken to reduce the harmful effects of hazards that remain ''in potentia'', or to manage harmful incidents that ...
is an important part of all of the
Sustainable Development Goals
The ''2030 Agenda for Sustainable Development'', adopted by all United Nations (UN) members in 2015, created 17 world Sustainable Development Goals (SDGs). The aim of these global goals is "peace and prosperity for people and the planet" – wh ...
.
Definitions and types
Various definitions of pollution exist, which may or may not recognize certain types, such as
noise pollution
Noise pollution, or sound pollution, is the propagation of noise or sound with potential harmful effects on humans and animals. The source of outdoor noise worldwide is mainly caused by machines, transport and propagation systems.Senate Publi ...
or
greenhouse gas
Greenhouse gases (GHGs) are the gases in the atmosphere that raise the surface temperature of planets such as the Earth. Unlike other gases, greenhouse gases absorb the radiations that a planet emits, resulting in the greenhouse effect. T ...
es. The United States
Environmental Protection Administration defines pollution as "Any substances in water, soil, or air that degrade the natural quality of the environment, offend the senses of sight, taste, or smell, or cause a health hazard. The usefulness of the natural resource is usually impaired by the presence of pollutants and contaminants." In contrast, the
United Nations
The United Nations (UN) is the Earth, global intergovernmental organization established by the signing of the Charter of the United Nations, UN Charter on 26 June 1945 with the stated purpose of maintaining international peace and internationa ...
considers pollution to be the "presence of substances and heat in environmental media (air, water, land) whose nature, location, or quantity produces undesirable environmental effects."
The major forms of pollution are listed below along with the particular
contaminants
Contamination is the presence of a constituent, impurity, or some other undesirable element that renders something unsuitable, unfit or harmful for the physical body, natural environment, workplace, etc.
Types of contamination
Within the scie ...
relevant to each of them:
*
Air pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
: the release of chemicals and
particulates
Particulate matter (PM) or particulates are microscopic particles of solid or liquid matter suspension (chemistry), suspended in the atmosphere of Earth, air. An ''aerosol'' is a mixture of particulates and air, as opposed to the particulate ...
into the atmosphere. Common gaseous pollutants include
carbon monoxide
Carbon monoxide (chemical formula CO) is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...
,
sulfur dioxide
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is r ...
,
chlorofluorocarbon
Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly Halogenation, halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F). They are produced as volatility (chemistry), volat ...
s (CFCs) and
nitrogen oxide
Nitrogen oxide may refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds:
Charge-neutral
*Nitric oxide (NO), nitrogen(II) oxide, or nitrogen monoxide
* Nitrogen dioxide (), nitrogen(IV) oxide
* Nitrogen trioxide (), o ...
s produced by
industry
Industry may refer to:
Economics
* Industry (economics), a generally categorized branch of economic activity
* Industry (manufacturing), a specific branch of economic activity, typically in factories with machinery
* The wider industrial sector ...
and motor vehicles. Photochemical
ozone
Ozone () (or trioxygen) is an Inorganic compound, inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , break ...
and
smog
Smog, or smoke fog, is a type of intense air pollution. The word "smog" was coined in the early 20th century, and is a portmanteau of the words ''smoke'' and ''fog'' to refer to smoky fog due to its opacity, and odour. The word was then inte ...
are created as nitrogen oxides and
hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually fain ...
s react to sunlight.
Particulate matter
Particulate matter (PM) or particulates are microscopic particles of solid or liquid matter suspended in the air. An ''aerosol'' is a mixture of particulates and air, as opposed to the particulate matter alone, though it is sometimes defin ...
, or fine dust is characterized by their
micrometre
The micrometre (English in the Commonwealth of Nations, Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a uni ...
size PM
10 to PM
2.5.
*
Electromagnetic pollution: the overabundance of
electromagnetic radiation
In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength ...
in their
non-ionizing form, such as radio and television transmissions, Wi-fi etc. Although there is no demonstrable effect on humans there can be interference with radio-astronomy and effects on safety systems of aircraft and cars.
*
Light pollution
Light pollution is the presence of any unwanted, inappropriate, or excessive artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting sources, during the ...
: includes light trespass,
over-illumination and
astronomical
Astronomy is a natural science that studies celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall evolution. Objects of interest include ...
interference.
*
Littering: the criminal throwing of inappropriate man-made objects, unremoved, onto public and private properties.
*
Noise pollution
Noise pollution, or sound pollution, is the propagation of noise or sound with potential harmful effects on humans and animals. The source of outdoor noise worldwide is mainly caused by machines, transport and propagation systems.Senate Publi ...
: which encompasses
roadway noise
Roadway noise is the collective sound energy emanating from motor vehicles. It consists chiefly of road surface, tire, engine/transmission, aerodynamic, and Brake, braking elements. Noise of rolling tires driving on pavement is found to be the ...
,
aircraft noise
Aircraft noise pollution refers to noise produced by aircraft in flight that has been associated with several negative stress-mediated health effects, from sleep disorders to cardiovascular disorders. Governments have enacted extensive control ...
,
industrial noise
Occupational noise is the amount of acoustic energy received by an employee's auditory system when they are working in the industry. Occupational noise, or industrial noise, is often a term used in occupational safety and health, as sustained expos ...
as well as high-intensity
sonar
Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects o ...
.
*
Plastic pollution
Plastic pollution is the accumulation of plastic objects and particles (e.g. plastic bottles, bags and microbeads) in the Earth's environment that adversely affects humans, wildlife and their habitat. Plastics that act as pollutants are catego ...
: involves the accumulation of plastic products and
microplastics
Microplastics are "synthetic solid particles or polymeric matrices, with regular or irregular shape and with size ranging from 1 μm to 5 mm, of either primary or secondary manufacturing origin, which are insoluble in water." Microplastics a ...
in the environment that adversely affects wildlife, wildlife habitat, or humans.
*
Soil contamination
Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic (human-made) chemicals or other alteration in the natural soil environment. It is typically caused by industrial activit ...
occurs when chemicals are released by spill or underground leakage. Among the most significant
soil contaminants are
hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually fain ...
s,
heavy metals
upright=1.2, Crystals of lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead
Heavy metals is a controversial and ambiguous term for metallic elements with relatively h ...
,
MTBE
Methyl ''tert''-butyl ether (MTBE), also known as ''tert''-butyl methyl ether, is an organic compound with a structural formula (CH3)3COCH3. MTBE is a volatile, flammable, and colorless liquid that is sparingly soluble in water. Primarily used as ...
,
herbicides
Herbicides (, ), also commonly known as weed killers, are substances used to control undesired plants, also known as weeds.EPA. February 201Pesticides Industry. Sales and Usage 2006 and 2007: Market Estimates. Summary in press releasMain page f ...
,
pesticides
Pesticides are substances that are used to pest control, control pest (organism), pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for a ...
and
chlorinated hydrocarbons.
*
Radioactive contamination
Radioactive contamination, also called radiological pollution, is the deposition of, or presence of Radioactive decay, radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is uni ...
, resulting from 20th century activities in
atomic physics
Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus. Atomic physics typically refers to the study of atomic structure and the interaction between atoms. It is primarily concerned wit ...
, such as nuclear power generation and nuclear weapons research, manufacture and deployment. (See
alpha emitters and
actinides in the environment.)
*
Thermal pollution
Thermal pollution, sometimes called "thermal enrichment", is the degradation of water quality by any process that changes ambient water temperature. Thermal pollution is the rise or drop in the temperature of a natural body of water caused by h ...
, is a
temperature
Temperature is a physical quantity that quantitatively expresses the attribute of hotness or coldness. Temperature is measurement, measured with a thermometer. It reflects the average kinetic energy of the vibrating and colliding atoms making ...
change in natural water bodies caused by human influence, such as use of water as coolant in a power plant.
*
Visual pollution
The visual system is the physiological basis of visual perception (the ability to detect and process light). The system detects, transduces and interprets information concerning light within the visible range to construct an image and buil ...
, which can refer to the presence of overhead
power lines, motorway
billboards
A billboard (also called a hoarding in the UK and many other parts of the world) is a large out-of-home advertising, outdoor advertising structure (a billing board), typically found in high-traffic areas such as alongside busy roads. Billboard ...
,
scarred landform
A landform is a land feature on the solid surface of the Earth or other planetary body. They may be natural or may be anthropogenic (caused or influenced by human activity). Landforms together make up a given terrain, and their arrangement ...
s (as from
strip mining
Surface mining, including strip mining, open-pit mining and mountaintop removal mining, is a broad category of mining in which soil and rock overlying the mineral deposit (the overburden) are removed, in contrast to underground mining, in which ...
), open storage of trash,
municipal solid waste
Municipal solid waste (MSW), commonly known as trash or garbage in the American English, United States and rubbish in British English, Britain, is a List of waste types, waste type consisting of everyday items that are discarded by the public. ...
or
space debris
Space debris (also known as space junk, space pollution, space waste, space trash, space garbage, or cosmic debris) are defunct human-made objects in spaceprincipally in Earth orbitwhich no longer serve a useful function. These include dere ...
.
* Water pollution, caused by the discharge of industrial wastewater from commercial and industrial waste (intentionally or through spills) into surface waters; discharges of untreated
sewage
Sewage (or domestic sewage, domestic wastewater, municipal wastewater) is a type of wastewater that is produced by a community of people. It is typically transported through a sewerage, sewer system. Sewage consists of wastewater discharged fro ...
and chemical contaminants, such as chlorine, from treated sewage; and releases of waste and contaminants into
surface runoff
Surface runoff (also known as overland flow or terrestrial runoff) is the unconfined flow of water over the ground surface, in contrast to ''channel runoff'' (or ''stream flow''). It occurs when excess rainwater, stormwater, meltwater, or other ...
flowing to surface waters (including urban runoff and agricultural runoff, which may contain chemical fertilizers and pesticides, as well as human feces from open defecation).
Natural causes
One of the most significant natural sources of pollution are
volcano
A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most oft ...
es, which during eruptions release large quantities of harmful gases into the atmosphere. Volcanic gases include carbon dioxide, which can be fatal in large concentrations and contributes to
climate change
Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...
, hydrogen halides which can cause
acid rain
Acid rain is rain or any other form of Precipitation (meteorology), precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). Most water, including drinking water, has a neutral pH that exists b ...
, sulfur dioxides, which are harmful to animals and damage the
ozone layer
The ozone layer or ozone shield is a region of Earth's stratosphere that absorption (electromagnetic radiation), absorbs most of the Sun's ultraviolet radiation. It contains a high concentration of ozone (O3) in relation to other parts of the a ...
, and
hydrogen sulfide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is toxic, corrosive, and flammable. Trace amounts in ambient atmosphere have a characteristic foul odor of rotten eggs. Swedish chemist ...
s, which are capable of killing humans at concentrations of less than 1 part per thousand. Volcanic emissions also include fine and ultrafine particles which may contain toxic chemicals and substances such as
arsenic
Arsenic is a chemical element; it has Symbol (chemistry), symbol As and atomic number 33. It is a metalloid and one of the pnictogens, and therefore shares many properties with its group 15 neighbors phosphorus and antimony. Arsenic is not ...
,
lead
Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...
, and
mercury.
Wildfire
A wildfire, forest fire, or a bushfire is an unplanned and uncontrolled fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire may be more specifically identified as a ...
s, which can be caused naturally by
lightning strike
A lightning strike or lightning bolt is a lightning event in which an electric discharge takes place between the atmosphere and the ground. Most originate in a cumulonimbus cloud and terminate on the ground, called cloud-to-ground (CG) lightning ...
s, are also a significant source of air pollution. Wildfire smoke contains significant quantities of both carbon dioxide and carbon monoxide, which can cause
suffocation. Large quantities of
fine particulates are found within wildfire smoke as well, which pose a health risk to animals.
Human generation
Motor vehicle emissions
Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline (petrol), diesel fuel, fuel oil, biodiesel blends, or coal. According to the type of engine, it is discharged into the atmosphere through ...
are one of the leading causes of air pollution.
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
,
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
,
Russia
Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...
,
India
India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...
,
Mexico
Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...
, and
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
are the world leaders in air pollution emissions. Principal stationary pollution sources include
chemical plant
A chemical plant is an industrial process plant that manufactures (or otherwise processes) chemicals, usually on a large scale. The general objective of a chemical plant is to create new material wealth via the chemical or biological transfor ...
s, coal-fired
power plants,
oil refineries
An oil refinery or petroleum refinery is an industrial process plant where petroleum (crude oil) is transformed and refined into products such as gasoline (petrol), diesel fuel, asphalt base, fuel oils, heating oil, kerosene, liquefied pet ...
,
petrochemical
Petrochemicals (sometimes abbreviated as petchems) are the chemical products obtained from petroleum by refining. Some chemical compounds made from petroleum are also obtained from other fossil fuels, such as coal or natural gas, or renewable s ...
plants,
nuclear waste
Radioactive waste is a type of hazardous waste that contains radioactive material. It is a result of many activities, including nuclear medicine, nuclear research, nuclear power generation, nuclear decommissioning, rare-earth mining, and nuclear ...
disposal activity, incinerators, large
livestock farms (dairy cows, pigs, poultry, etc.),
PVC factories, metals production factories, plastics factories, and other
heavy industry
Heavy industry is an industry that involves one or more characteristics such as large and heavy products; large and heavy equipment and facilities (such as heavy equipment, large machine tools, huge buildings and large-scale infrastructure); o ...
. Agricultural air pollution comes from contemporary practices which include clear felling and burning of natural vegetation as well as spraying of pesticides and herbicides.
About 400 million metric tons of
hazardous waste
Hazardous waste is waste that must be handled properly to avoid damaging human health or the environment. Waste can be hazardous because it is Toxicity, toxic, Chemical reaction, reacts violently with other chemicals, or is Corrosion, corrosive, ...
s are generated each year. The United States alone produces about 250 million metric tons. Americans constitute less than 5% of the
world's population, but produce roughly 25% of the world's
, and generate approximately 30% of
world's waste. In 2007,
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
overtook the United States as the world's biggest producer of , while still far behind based on per capita pollution (ranked 78th among the world's nations).

Chlorinated hydrocarbons (CFH), heavy metals (such as chromium, cadmium – found in rechargeable batteries, and lead – found in lead paint, aviation fuel, and even in certain countries, gasoline), MTBE, zinc, arsenic, and benzene are some of the most frequent soil contaminants. A series of press reports published in 2001, culminating in the publication of the book Fateful Harvest, revealed a widespread practise of recycling industrial leftovers into fertilizer, resulting in metal poisoning of the soil. Ordinary municipal
landfill
A landfill is a site for the disposal of waste materials. It is the oldest and most common form of waste disposal, although the systematic burial of waste with daily, intermediate and final covers only began in the 1940s. In the past, waste was ...
s 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
Polychlorinated dibenzodioxins (PCDDs), or simply dioxins, are a group of long-lived polyhalogenated organic compounds that are primarily anthropogenic, and contribute toxic, persistent organic pollution in the environment.
They are commonly ...
, commonly called ''dioxins'' for simplicity, such as
TCDD.
Pollution can also occur as a result of natural disasters. Hurricanes, for example, frequently result in sewage contamination and petrochemical spills from burst boats or automobiles. When coastal oil rigs or refineries are involved, larger-scale and environmental damage is not unusual. When accidents occur, some pollution sources, such as nuclear power stations or oil ships, can create extensive and potentially catastrophic emissions.
Plastic pollution is choking our oceans by making plastic gyres, entangling marine animals, poisoning our food and water supply, and ultimately inflicting havoc on the health and well-being of humans and wildlife globally. With the exception of a small amount that has been incinerating, virtually every piece of plastic that was ever made in the past still exists in one form or another. And since most of the plastics do not biodegrade in any meaningful sense, all that
plastic waste
Plastic pollution is the accumulation of plastic objects and particles (e.g. plastic bottles, bags and microbeads) in the Earth's environment that adversely affects humans, wildlife and their habitat. Plastics that act as pollutants are cate ...
could exist for hundreds or even thousands of years. If plastic production is not circumscribed, plastic pollution will be disastrous and will eventually outweigh fish in oceans.

Raised levels of
greenhouse gases
Greenhouse gases (GHGs) are the gases in the atmosphere that raise the surface temperature of planets such as the Earth. Unlike other gases, greenhouse gases absorb the radiations that a planet emits, resulting in the greenhouse effect. T ...
such as
carbon dioxide
Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...
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.
In February 2007, a report by the
Intergovernmental Panel on Climate Change
The Intergovernmental Panel on Climate Change (IPCC) is an intergovernmental body of the United Nations. Its job is to "provide governments at all levels with scientific information that they can use to develop climate policies". The World Met ...
(IPCC), representing the work of 2,500 scientists, economists, and policymakers from more than 120 countries, confirmed that humans have been the primary cause of global warming since 1950. Humans have ways to cut
greenhouse gas emissions
Greenhouse gas (GHG) emissions from human activities intensify the greenhouse effect. This contributes to climate change. Carbon dioxide (), from burning fossil fuels such as coal, petroleum, oil, and natural gas, is the main cause of climate chan ...
and avoid the consequences of global warming, a major climate report concluded. But to change the climate, the transition from
fossil fuels
A fossil fuel is a flammable carbon compound- or hydrocarbon-containing material formed naturally in the Earth's crust from the buried remains of prehistoric organisms (animals, plants or microplanktons), a process that occurs within geologica ...
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).
Effects
Human health

Pollution affects humans in every part of the world. An October 2017 study by the Lancet Commission on Pollution and Health found that global pollution, specifically toxic air, water, soil and workplaces, kills nine million people annually, which is triple the number of deaths caused by AIDS, tuberculosis and malaria combined, and 15 times higher than deaths caused by wars and other forms of human violence. The study concluded that "pollution is one of the great existential challenges of the
Anthropocene
''Anthropocene'' is a term that has been used to refer to the period of time during which human impact on the environment, humanity has become a planetary force of change. It appears in scientific and social discourse, especially with respect to ...
era. Pollution endangers the stability of the Earth's support systems and threatens the continuing survival of human societies."
Adverse
air quality
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
can kill many organisms, including humans. Ozone pollution can cause
respiratory disease
Respiratory diseases, or lung diseases, are pathological conditions affecting the organs and tissues that make gas exchange difficult in air-breathing animals. They include conditions of the respiratory tract including the trachea, bronchi, ...
,
cardiovascular disease
Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina, heart attack), heart failure, hypertensive heart disease, rheumati ...
,
throat
In vertebrate anatomy, the throat is the front part of the neck, internally positioned in front of the vertebrae. It contains the Human pharynx, pharynx and larynx. An important section of it is the epiglottis, separating the esophagus from the t ...
inflammation, chest pain, and
congestion. A 2010 analysis estimated that 1.2 million people died prematurely each year in
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
alone because of air pollution. China's high smog levels can damage the human body and cause various diseases. In 2019, air pollution caused 1.67 million deaths in India (17.8% of total deaths nationally). Studies have estimated that the number of people killed annually in the United States could be over 50,000. A study published in 2022 in ''
GeoHealth'' concluded that energy-related fossil fuel emissions in the United States cause 46,900–59,400 premature deaths each year and PM2.5-related illness and death costs the nation $537–$678 billion annually.
In the US, deaths caused by coal pollution were highest in 1999, but decreased sharply after 2007. The number dropped by about 95% by 2020, as coal plants have been closed or have
scrubbers installed.
In 2019,
water pollution
Water pollution (or aquatic pollution) is the contamination of Body of water, water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and ...
caused 1.4 million premature deaths.
Contamination of drinking water by untreated
sewage
Sewage (or domestic sewage, domestic wastewater, municipal wastewater) is a type of wastewater that is produced by a community of people. It is typically transported through a sewerage, sewer system. Sewage consists of wastewater discharged fro ...
in
developing countries
A developing country is a sovereign state with a less-developed Secondary sector of the economy, industrial base and a lower Human Development Index (HDI) relative to developed countries. However, this definition is not universally agreed upon. ...
is an issue, for example, over 732 million Indians (56% of the population) and over 92 million Ethiopians (92.9% of the population) do not have access to basic
sanitation
Sanitation refers to public health conditions related to clean drinking water and treatment and disposal of human excreta and sewage. Preventing human contact with feces is part of sanitation, as is hand washing with soap. Sanitation systems ...
. In 2013 over 10 million people in India fell ill with waterborne illnesses in 2013, and 1,535 people died, most of them children. , nearly 500 million Chinese lack access to safe drinking water.
Acute exposure to certain pollutants can have short and long term effects. Oil spills can cause
skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other animal coverings, such as the arthropod exoskeleton, have different ...
irritations and
rash
A rash is a change of the skin that affects its color, appearance, or texture.
A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cracke ...
es. Noise pollution induces
hearing loss
Hearing loss is a partial or total inability to hear. Hearing loss may be present at birth or acquired at any time afterwards. Hearing loss may occur in one or both ears. In children, hearing problems can affect the ability to acquire spo ...
,
high blood pressure
Hypertension, also known as high blood pressure, is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms itself. It is, however, a major ri ...
,
stress, and
sleep disturbance.
Mercury has been linked to
developmental deficits in children and
neurologic symptoms. Older people are significantly exposed to
diseases induced by air pollution. Those with heart or lung disorders are at additional risk. Children and infants are also at serious risk.
Lead
Lead () is a chemical element; it has Chemical symbol, symbol Pb (from Latin ) and atomic number 82. It is a Heavy metal (elements), heavy metal that is density, denser than most common materials. Lead is Mohs scale, soft and Ductility, malleabl ...
and other
heavy metals
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Heavy metals is a controversial and ambiguous term for metallic elements with relatively h ...
have been shown to cause neurological problems, intellectual disabilities and behavioural problems. Chemical and
radioactive
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ...
substances can
cause
Causality is an influence by which one event, process, state, or object (''a'' ''cause'') contributes to the production of another event, process, state, or object (an ''effect'') where the cause is at least partly responsible for the effect, ...
cancer
Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...
and
birth defect
A birth defect is an abnormal condition that is present at birth, regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can range from mild to severe. Birth de ...
s.
Socio economic impacts
The health impacts of pollution have both direct and lasting social consequences. A 2021 study found that exposure to pollution causes an increase in violent crime. A 2019 paper linked pollution to adverse school outcomes for children. A number of studies show that pollution has an adverse effect on the productivity of both indoor and outdoor workers.
Environment

Pollution has been found to be present widely in the natural
environment. A 2022 study published in ''
Environmental Science & Technology
''Environmental Science & Technology'' is a biweekly peer-reviewed scientific journal published since 1967 by the American Chemical Society. It covers research in environmental science and environmental technology, including environmental policy. ...
'' found that levels of anthropogenic chemical pollution have exceeded
planetary boundaries
Planetary boundaries are a framework to describe limits to the impacts of human activities on the Earth system. Beyond these limits, the environment may not be able to continue to self-regulate. This would mean the Earth system would leave th ...
and now threaten entire ecosystems around the world.
There are a number of effects of this:
*
Biomagnification
Biomagnification, also known as bioamplification or biological magnification, is the increase in concentration of a substance, e.g a pesticide, in the tissue (biology), tissues of organisms at successively higher levels in a food chain. This inc ...
describes situations where toxins (such as
heavy metals
upright=1.2, Crystals of lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead
Heavy metals is a controversial and ambiguous term for metallic elements with relatively h ...
) may pass through
trophic level
The trophic level of an organism is the position it occupies in a food web. Within a food web, a food chain is a succession of organisms that eat other organisms and may, in turn, be eaten themselves. The trophic level of an organism is the ...
s, becoming exponentially more concentrated in the process.

*
Carbon dioxide
Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...
emissions cause
ocean acidification
Ocean acidification is the ongoing decrease in the pH of the Earth's ocean. Between 1950 and 2020, the average pH of the ocean surface fell from approximately 8.15 to 8.05. Carbon dioxide emissions from human activities are the primary cause of ...
, the ongoing decrease in the pH of the Earth's oceans as becomes dissolved.
* The emission of
greenhouse gas
Greenhouse gases (GHGs) are the gases in the atmosphere that raise the surface temperature of planets such as the Earth. Unlike other gases, greenhouse gases absorb the radiations that a planet emits, resulting in the greenhouse effect. T ...
es leads to
global warming
Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes ...
which affects ecosystems in many ways.
*
Invasive species
An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...
can outcompete native species and reduce
biodiversity
Biodiversity is the variability of life, life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and Phylogenetics, phylogenetic diversity. Diversity is not distribut ...
. Invasive plants can contribute debris and biomolecules (
allelopathy
Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have ben ...
) that can alter soil and chemical compositions of an environment, often reducing native species
competitiveness
Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, individ ...
.
*
Nitrogen oxide
Nitrogen oxide may refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds:
Charge-neutral
*Nitric oxide (NO), nitrogen(II) oxide, or nitrogen monoxide
* Nitrogen dioxide (), nitrogen(IV) oxide
* Nitrogen trioxide (), o ...
s are removed from the air by rain and
fertilise land which can change the species composition of ecosystems.
*
Smog
Smog, or smoke fog, is a type of intense air pollution. The word "smog" was coined in the early 20th century, and is a portmanteau of the words ''smoke'' and ''fog'' to refer to smoky fog due to its opacity, and odour. The word was then inte ...
and haze can reduce the amount of sunlight received by plants to carry out
photosynthesis
Photosynthesis ( ) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabo ...
and leads to the production of
tropospheric ozone which damages plants.
* Soil can become infertile and unsuitable for plants. This will affect other
organism
An organism is any life, living thing that functions as an individual. Such a definition raises more problems than it solves, not least because the concept of an individual is also difficult. Many criteria, few of them widely accepted, have be ...
s in the
food web
A food web is the natural interconnection of food chains and a graphical representation of what-eats-what in an ecological community. Position in the food web, or trophic level, is used in ecology to broadly classify organisms as autotrophs or he ...
.
*
Sulfur dioxide
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is r ...
and
nitrogen oxide
Nitrogen oxide may refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds:
Charge-neutral
*Nitric oxide (NO), nitrogen(II) oxide, or nitrogen monoxide
* Nitrogen dioxide (), nitrogen(IV) oxide
* Nitrogen trioxide (), o ...
s can cause
acid rain
Acid rain is rain or any other form of Precipitation (meteorology), precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). Most water, including drinking water, has a neutral pH that exists b ...
which lowers the
pH value of soil.
* Organic pollution of watercourses can deplete
oxygen
Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...
levels and reduce species diversity.
Regulation and monitoring
Control

Pollution control is a term used in
environmental management
Environmental resource management or environmental management is the management of the interaction and impact of human societies on the environment. It is not, as the phrase might suggest, the management of the environment itself. Environment ...
. It refers to the control of
emissions and
effluents into air, water or soil. Without pollution control, the
waste
Waste are unwanted or unusable materials. Waste is any substance discarded after primary use, or is worthless, defective and of no use. A by-product, by contrast is a joint product of relatively minor Value (economics), economic value. A wast ...
products from
overconsumption
Overconsumption describes a situation where consumers overuse their available goods and services to where they can't, or don't want to, replenish or reuse them. In microeconomics, this is the point where the marginal cost of a consumer is greater ...
, 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
Waste minimisation is a set of processes and practices intended to reduce the amount of waste produced. By reducing or eliminating the generation of harmful and persistent wastes, waste minimisation supports efforts to promote a more sustain ...
are more desirable than pollution control. In the field of
land development
Land development is the alteration of landscape in any number of ways, such as:
* Changing landforms from a natural or semi-natural state for a purpose such as agriculture or House, housing
* subdivision (land), Subdividing real estate into Lot ( ...
,
low impact development is a similar technique for the prevention of
urban runoff
Urban runoff is surface runoff of rainwater, landscape irrigation, and car washing created by urbanization. Impervious surfaces (roads, parking lots and sidewalks) are constructed during land development. During rain, storms, and other Precipitati ...
.
Policy
Policy is a deliberate system of guidelines to guide decisions and achieve rational outcomes. A policy is a statement of intent and is implemented as a procedure or protocol. Policies are generally adopted by a governance body within an or ...
,
law
Law is a set of rules that are created and are enforceable by social or governmental institutions to regulate behavior, with its precise definition a matter of longstanding debate. It has been variously described as a science and as the ar ...
and monitoring/transparency/
life-cycle assessment
Life cycle assessment (LCA), also known as life cycle analysis, is a methodology for assessing the impacts associated with all the stages of the life cycle of a commercial product, process, or service. For instance, in the case of a manufact ...
-attached
economics
Economics () is a behavioral science that studies the Production (economics), production, distribution (economics), distribution, and Consumption (economics), consumption of goods and services.
Economics focuses on the behaviour and interac ...
could be developed and enforced to control pollution.
A review concluded that there is a lack of attention and action such as work on a
globally supported "formal
science
Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which stu ...
–
policy
Policy is a deliberate system of guidelines to guide decisions and achieve rational outcomes. A policy is a statement of intent and is implemented as a procedure or protocol. Policies are generally adopted by a governance body within an or ...
interface", e.g. to "
inform
Inform is a programming language and design system for interactive fiction originally created in 1993 by Graham Nelson. Inform can generate programs designed for the Z-machine, Z-code or Glulx virtual machines. Versions 1 through 5 were released ...
intervention, influence research, and guide funding".
In September 2023 a
Global Framework on Chemicals aiming to reduce pollution was agreed during an international conference in
Bonn
Bonn () is a federal city in the German state of North Rhine-Westphalia, located on the banks of the Rhine. With a population exceeding 300,000, it lies about south-southeast of Cologne, in the southernmost part of the Rhine-Ruhr region. This ...
, Germany. The framework includes 28 targets, for example, to "end the use of hazardous pesticides in agriculture where the risks have not been managed" by 2035.
Practices
*
Recycling
Recycling is the process of converting waste materials into new materials and objects. This concept often includes the recovery of energy from waste materials. The recyclability of a material depends on its ability to reacquire the propert ...
*
Reusing
*
Waste minimisation
Waste minimisation is a set of processes and practices intended to reduce the amount of waste produced. By reducing or eliminating the generation of harmful and persistent wastes, waste minimisation supports efforts to promote a more sustai ...
*
Mitigating
Mitigation is the reduction of something harmful that has occurred or the reduction of its harmful effects. It may refer to measures taken to reduce the harmful effects of hazards that remain ''in potentia'', or to manage harmful incidents that ...
* Pollution prevention
*
Compost
Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical, and biological properties. It is commonly prepared by Decomposition, decomposing plant and food waste, recycling organic materials, and man ...
Devices
*
Air pollution control
**
Green wall
A green wall is a vertical built structure intentionally covered by vegetation. Green walls include a vertically applied growth medium such as soil, substitute substrate, or hydroculture felt; as well as an integrated hydration and fertigation ...
**
Smog Tower
**
Thermal oxidizer
*
Bioremediation
Bioremediation broadly refers to any process wherein a biological system (typically bacteria, microalgae, fungi in mycoremediation, and plants in phytoremediation), living or dead, is employed for removing environmental pollutants from air, wate ...
*
Dust collection systems
**
Baghouses
**
Cyclones
In meteorology, a cyclone () is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere as viewed from above (opposite to an ant ...
**
Electrostatic precipitator
An electrostatic precipitator (ESP) is a filterless device that removes fine particles, such as dust and smoke, from a flowing gas using the force of an induced electrostatic charge minimally impeding the flow of gases through the unit.
In c ...
s
*
Scrubber
Scrubber systems (e.g. chemical scrubbers, gas scrubbers) are a diverse group of air pollution control devices that can be used to remove some particulates and/or gases from industrial exhaust streams. An early application of a carbon dioxide scr ...
s
**
Baffle spray scrubber
**
Cyclonic spray scrubber
**
Ejector venturi scrubber
**
Mechanically aided scrubber
**
Spray tower
**
Wet scrubber
The term wet scrubber describes a variety of devices that remove pollutants from a Industrial furnace, furnace flue gas or from other gas streams. In a wet scrubber, the polluted gas stream is brought into contact with the scrubbing liquid, by sp ...
*
Sewage treatment
Sewage treatment is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable to discharge to the surrounding environment or an intended reuse application, thereby preventing water p ...
**
Sedimentation
Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to th ...
(Primary treatment)
**
Activated sludge biotreaters (Secondary treatment; also used for industrial wastewater)
**
Aerated lagoons
**
Constructed wetlands
A constructed wetland is an artificial wetland to treat sewage, greywater, stormwater runoff or industrial wastewater. It may also be designed for land reclamation after mining, or as a mitigation step for natural areas lost to land developme ...
(also used for urban runoff)
*
Industrial wastewater treatment
Industrial wastewater treatment describes the processes used for Wastewater treatment, treating wastewater that is produced by industries as an undesirable by-product. After treatment, the treated industrial wastewater (or effluent) may be reus ...
**
API oil-water separators
**
Biofilter
Biofiltration is a pollution control technique using a bioreactor containing living material to capture and biologically degrade pollutants. Common uses include processing waste water, capturing harmful chemicals or silt from surface runoff, a ...
s
**
Dissolved air flotation (DAF)
**
Powdered activated carbon treatment
Powdered Activated Carbon Treatment (PACT) is a wastewater technology in which powdered activated carbon is added to an anaerobic or aerobic treatment system.Jafarinejad, S. “Activated sludge combined with powdered activated carbon (PACT proces ...
**
Ultrafiltration
Ultrafiltration (UF) is a variety of membrane filtration in which forces such as pressure or concentration gradients lead to a separation through a semipermeable membrane. Suspended solids and solutes of high molecular weight are retained in t ...
*
Vapor recovery systems
*
Phytoremediation
Phytoremediation technologies use living plants to clean up soil, air and water contaminated with hazardous contaminants. It is defined as "the use of green plants and the associated microorganisms, along with proper soil amendments and agronom ...
Cost
Pollution has a cost. Manufacturing activities that cause
air pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
impose health and clean-up costs on the whole of society. A manufacturing activity that causes air pollution is an example of a negative
externality
In economics, an externality is an Indirect costs, indirect cost (external cost) or indirect benefit (external benefit) to an uninvolved third party that arises as an effect of another party's (or parties') activity. Externalities can be conside ...
in production. A negative externality in production occurs "when a firm's production reduces the well-being of others who are not compensated by the firm."
For example, if a laundry firm exists near a polluting steel manufacturing firm, there will be increased costs for the laundry firm because of the dirt and smoke produced by the steel manufacturing firm. If external costs exist, such as those created by pollution, the manufacturer will choose to produce more of the product than would be produced if the manufacturer were required to pay all associated environmental costs. Because responsibility or consequence for self-directed action lies partly outside the self, an element of
externalization is involved. If there are external benefits, such as in
public safety
Public security or public safety is the prevention of and protection from events that could endanger the safety and security of the public from significant danger, injury, or property damage. It is often conducted by a state government to ensu ...
, less of the good may be produced than would be the case if the producer were to receive payment for the external benefits to others. Goods and services that involve negative externalities in production, such as those that produce pollution, tend to be overproduced and underpriced since the externality is not being priced into the market.
Pollution can also create costs for the firms producing the pollution. Sometimes firms choose, or are forced by regulation, to reduce the amount of pollution that they are producing. The associated costs of doing this are called abatement costs, or
marginal abatement cost
Abatement cost is the cost of reducing environmental negatives such as pollution. Marginal cost is an economic concept that measures the cost of an additional unit. The marginal abatement cost, in general, measures the cost of reducing one more ...
s if measured by each additional unit. In 2005 pollution abatement capital expenditures and operating costs in the US amounted to nearly $27 billion.
Dirtiest industries
The
Pure Earth, an international non-for-profit organization dedicated to eliminating life-threatening pollution in the developing world, issues an annual list of some of the world's most polluting industries. Below is the list for 2016:
*
Lead–acid battery
The lead–acid battery is a type of rechargeable battery first invented in 1859 by French physicist Gaston Planté. It was the first type of rechargeable battery to be invented. Compared to modern rechargeable batteries, lead–acid batteries ha ...
recycling
*
Mining
Mining is the Resource extraction, extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agriculture, agricultural processes, or feasib ...
and
extractive metallurgy
Extractive metallurgy is a branch of metallurgical engineering wherein process and methods of extraction of metals from their natural mineral deposits are studied. The field is a materials science, covering all aspects of the types of ore, was ...
*
Lead smelting
Plants for the production of lead are generally referred to as lead smelters. Primary lead production begins with sintering. Concentrated lead ore is fed into a sintering machine with iron, silica, limestone fluxes, coke, soda ash, pyrite, zinc ...
*
Tanning
*
Artisanal mining
Artisanal and small-scale mining (ASM) is a blanket term for a type of subsistence mining involving a miner who may or may not be officially employed by a List of mining companies, mining company but works independently, mining minerals using the ...
*
Landfill
A landfill is a site for the disposal of waste materials. It is the oldest and most common form of waste disposal, although the systematic burial of waste with daily, intermediate and final covers only began in the 1940s. In the past, waste was ...
s
*
Industrial park
An industrial park, also known as industrial estate or trading estate, is an area zoned and planned for the purpose of industrial development. An industrial park can be thought of as a more heavyweight version of a business park or office par ...
s
*
Chemical industry
The chemical industry comprises the companies and other organizations that develop and produce industrial, specialty and other chemicals. Central to the modern world economy, the chemical industry converts raw materials ( oil, natural gas, air, ...
*
Manufacturing
Manufacturing is the creation or production of goods with the help of equipment, labor, machines, tools, and chemical or biological processing or formulation. It is the essence of the
secondary sector of the economy. The term may refer ...
*
Dyeing
Dyeing is the application of dyes or pigments on textile materials such as fibers, yarns, and fabrics with the goal of achieving color with desired color fastness. Dyeing is normally done in a special solution containing dyes and particular ...
A 2018 report by the
Institute for Agriculture and Trade Policy and
GRAIN
A grain is a small, hard, dry fruit (caryopsis) – with or without an attached husk, hull layer – harvested for human or animal consumption. A grain crop is a grain-producing plant. The two main types of commercial grain crops are cereals and ...
says that the meat and dairy industries are poised to surpass the oil industry as the world's worst polluters.
Textile industry
Fossil fuel related industries
Outdoor air pollution attributable to fossil fuel use alone causes ~3.61 million deaths annually, making it one
of the top contributors to human death, beyond being a major driver of climate change whereby greenhouse gases are considered per se as a form of pollution .
Socially optimal level
Society derives some indirect
utility
In economics, utility is a measure of a certain person's satisfaction from a certain state of the world. Over time, the term has been used with at least two meanings.
* In a normative context, utility refers to a goal or objective that we wish ...
from pollution; otherwise, there would be no incentive to pollute. This utility may come from the consumption of goods and services that inherently create pollution (albeit the level can vary) or lower prices or lower required efforts (or inconvenience) to abandon or substitute these goods and services. Therefore, it is important that policymakers attempt to balance these indirect benefits with the costs of pollution in order to achieve an efficient outcome.

It is possible to use
environmental economics
Environmental economics is a sub-field of economics concerned with environmental issues. It has become a widely studied subject due to growing environmental concerns in the twenty-first century. Environmental economics "undertakes theoretical ...
to determine which level of pollution is deemed the social optimum. For economists, pollution is an "external cost and occurs only when one or more individuals suffer a loss of welfare". There is a socially optimal level of pollution at which
welfare
Welfare may refer to:
Philosophy
*Well-being (happiness, prosperity, or flourishing) of a person or group
* Utility in utilitarianism
* Value in value theory
Economics
* Utility, a general term for individual well-being in economics and decision ...
is maximized. This is because consumers derive utility from the good or service manufactured, which will outweigh the
social cost
Social cost in neoclassical economics is the sum of the private costs resulting from a transaction and the costs imposed on the consumers as a consequence of being exposed to the transaction for which they are not compensated or charged. In other w ...
of pollution until a certain point. At this point the damage of one extra unit of pollution to society, the
marginal cost
In economics, the marginal cost is the change in the total cost that arises when the quantity produced is increased, i.e. the cost of producing additional quantity. In some contexts, it refers to an increment of one unit of output, and in others it ...
of pollution, is exactly equal to the
marginal benefit
Marginal utility, in mainstream economics, describes the change in ''utility'' (pleasure or satisfaction resulting from the consumption) of one unit of a good or service. Marginal utility can be positive, negative, or zero. Negative marginal utilit ...
of consuming one more unit of the good or service.
Moreover, the feasibility of pollution reduction rates could also be a factor of calculating optimal levels. While a study puts the global mean loss of life expectancy (LLE; similar to
YPLL) from air pollution in 2015 at 2.9 years (substantially more than, for example, 0.3 years from all forms of direct violence), it also indicated that a significant fraction of the LLE is unavoidable in terms of current economical-technological feasibility such as aeolian dust and wildfire emission control.
In markets with pollution, or other negative externalities in production, the
free market
In economics, a free market is an economic market (economics), system in which the prices of goods and services are determined by supply and demand expressed by sellers and buyers. Such markets, as modeled, operate without the intervention of ...
equilibrium will not account for the costs of pollution on society. If the social costs of pollution are higher than the private costs incurred by the firm, then the true supply curve will be higher. The point at which the social marginal cost and market
demand
In economics, demand is the quantity of a goods, good that consumers are willing and able to purchase at various prices during a given time. In economics "demand" for a commodity is not the same thing as "desire" for it. It refers to both the desi ...
intersect gives the socially optimal level of pollution. At this point, the quantity will be lower and the price will be higher in comparison to the free market equilibrium.
Therefore, the free market outcome could be considered a
market failure
In neoclassical economics, market failure is a situation in which the allocation of goods and services by a free market is not Pareto efficient, often leading to a net loss of economic value.Paul Krugman and Robin Wells Krugman, Robin Wells (2006 ...
because it "does not maximize efficiency".
This model can be used as a basis to evaluate different methods of internalizing the externality, such as
tariff
A tariff or import tax is a duty (tax), duty imposed by a national Government, government, customs territory, or supranational union on imports of goods and is paid by the importer. Exceptionally, an export tax may be levied on exports of goods ...
s, a
Pigouvian tax
A Pigouvian tax (also spelled Pigovian tax) is a tax on any Market (economics), market activity that generates negative externalities (i.e., external costs incurred by third parties that are not included in the market price). It is a method that ...
(such as a
carbon tax
A carbon tax is a tax levied on the carbon emissions from producing goods and services. Carbon taxes are intended to make visible the hidden Social cost of carbon, social costs of carbon emissions. They are designed to reduce greenhouse gas emis ...
) and
cap and trade
Carbon emission trading (also called carbon market, emission trading scheme (ETS) or cap and trade) is a type of emissions trading scheme designed for carbon dioxide (CO2) and other greenhouse gases (GHGs). A form of carbon price, carbon pricing ...
systems.
History
Prior to 19th century
Air pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
has always accompanied civilizations. Pollution started from
prehistoric times
Prehistory, also called pre-literary history, is the period of human history between the first known use of stone tools by hominins million years ago and the beginning of recorded history with the invention of writing systems. The use o ...
, when humans created the first
fire
Fire is the rapid oxidation of a fuel in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products.
Flames, the most visible portion of the fire, are produced in the combustion re ...
s. According to a 1983 article in the journal ''Science,'' "
soot
Soot ( ) is a mass of impure carbon particles resulting from the incomplete combustion of hydrocarbons. Soot is considered a hazardous substance with carcinogenic properties. Most broadly, the term includes all the particulate matter produced b ...
" found on ceilings of prehistoric caves provides ample evidence of the high levels of pollution that was associated with inadequate ventilation of open fires."
Metal
forging
Forging is a manufacturing process involving the shaping of metal using localized compression (physics), compressive forces. The blows are delivered with a hammer (often a power hammer) or a die (manufacturing), die. Forging is often classif ...
appears to be a key turning point in the creation of significant air pollution levels outside the home. Core samples of
glaciers in Greenland indicate increases in pollution associated with Greek, Roman, and Chinese metal production.

The burning of coal and wood, and the presence of many horses in concentrated areas made the cities the primary sources of pollution.
King Edward I
Edward I (17/18 June 1239 – 7 July 1307), also known as Edward Longshanks and the Hammer of the Scots (Latin: Malleus Scotorum), was King of England from 1272 to 1307. Concurrently, he was Lord of Ireland, and from 1254 ...
of England banned the burning of
mineral coal by proclamation in
London
London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Wester ...
in 1306, after its smoke became a problem; the fuel was named
sea-coal at the time, getting its name from the fact that it was delivered form overseas (as opposed to
charcoal
Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, ca ...
, which was referred to as "coal").
19th century
The Industrial Revolution gave birth to environmental pollution as we know it today. London also recorded one of the earliest extreme cases of
water quality
Water quality refers to the chemical, physical, and biological characteristics of water based on the standards of its usage. It is most frequently used by reference to a set of standards against which compliance, generally achieved through tr ...
problems with the
Great Stink
The Great Stink was an event in Central London during July and August 1858 in which the hot weather exacerbated the smell of untreated human waste and industrial effluent that was present on the banks of the River Thames. The problem had been ...
on the
Thames
The River Thames ( ), known alternatively in parts as the River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the second-longest in the United Kingdom, after th ...
of 1858, which led to the construction of the
London sewerage system
The London sewer system is part of the water infrastructure serving London, England. The modern system was developed during the late 19th century, and as London has grown the system has been expanded. It is currently owned and operated by Thame ...
soon afterward. Pollution issues escalated as
population growth
Population growth is the increase in the number of people in a population or dispersed group. The World population, global population has grown from 1 billion in 1800 to 8.2 billion in 2025. Actual global human population growth amounts to aroun ...
far exceeded the ability of neighborhoods to handle their waste problem. Reformers began to demand sewer systems and clean water.
In 1870, the sanitary conditions in
Berlin
Berlin ( ; ) is the Capital of Germany, capital and largest city of Germany, by both area and List of cities in Germany by population, population. With 3.7 million inhabitants, it has the List of cities in the European Union by population withi ...
were among the worst in Europe.
August Bebel
Ferdinand August Bebel (; 22 February 1840 – 13 August 1913) was a German socialist activist and politician. He was one of the principal founders of the Social Democratic Party of Germany (SPD).
Bebel, a woodworker by trade, co-founded the Sa ...
recalled conditions before a modern
sewer system was built in the late 1870s:
20th and 21st century
The primitive conditions were intolerable for a world national capital, and the
Imperial German government brought in its scientists, engineers, and urban planners to solve the deficiencies and forge Berlin as the world's model city. A British expert in 1906 concluded that Berlin represented "the most complete application of science, order and method of public life," adding "it is a marvel of civic administration, the most modern and most perfectly organized city that there is."
The emergence of great factories and consumption of immense quantities of coal gave rise to unprecedented
air pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
, and the large volume of industrial chemical discharges added to the growing load of untreated human waste.
Chicago
Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...
and
Cincinnati
Cincinnati ( ; colloquially nicknamed Cincy) is a city in Hamilton County, Ohio, United States, and its county seat. Settled in 1788, the city is located on the northern side of the confluence of the Licking River (Kentucky), Licking and Ohio Ri ...
were the first two American cities to enact laws ensuring cleaner air in 1881. Pollution became a significant issue in the United States in the early twentieth century, as
progressive reformers took issue with air pollution caused by coal burning, water pollution caused by bad sanitation, and street pollution caused by the three million horses who worked in American cities in 1900, generating large quantities of urine and
manure
Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nut ...
. As historian Martin Melosi notes, the generation that first saw automobiles replacing horses saw cars as "miracles of cleanliness". By the 1940s, automobile-caused
smog
Smog, or smoke fog, is a type of intense air pollution. The word "smog" was coined in the early 20th century, and is a portmanteau of the words ''smoke'' and ''fog'' to refer to smoky fog due to its opacity, and odour. The word was then inte ...
was a significant issue in
Los Angeles
Los Angeles, often referred to by its initials L.A., is the List of municipalities in California, most populous city in the U.S. state of California, and the commercial, Financial District, Los Angeles, financial, and Culture of Los Angeles, ...
.
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
The United States Department of the Interior (DOI) is an executive department of the U.S. federal government responsible for the management and conservation of most federal lands and natural resources. It also administers programs relatin ...
. The cities of Los Angeles experienced extreme smog events and
Donora, Pennsylvania, in the late 1940s, serving as another public reminder.
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. Awareness of atmospheric pollution spread widely after World War II, with fears triggered by reports of
radioactive fallout from atomic warfare and testing. Then a non-nuclear event – the Great Smog of 1952 in London – killed at least 4000 people. This prompted some of the first major modern environmental legislation: the
Clean Air Act of 1956.
Pollution began to draw significant 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
The Clean Water Act (CWA) is the primary federal law in the United States governing water pollution. Its objective is to restore and maintain the chemical, physical, and biological integrity of the nation's waters; recognizing the primary respo ...
, and the
National Environmental Policy Act
The National Environmental Policy Act (NEPA) is a United States environmental law designed to promote the enhancement of the environment. It created new laws requiring U.S. federal government agencies to evaluate the environmental impacts of ...
.

Severe incidents of pollution helped increase consciousness.
PCB dumping in the
Hudson River
The Hudson River, historically the North River, is a river that flows from north to south largely through eastern New York (state), New York state. It originates in the Adirondack Mountains at Henderson Lake (New York), Henderson Lake in the ...
resulted in a ban by the
EPA on consumption of its fish in 1974. National news stories in the late 1970s – especially the long-term
dioxin contamination at
Love Canal
Love Canal was a neighborhood in Niagara Falls, New York, United States, infamous as the location of a landfill that became the site of an environmental disaster discovered in 1977. Decades of dumping toxic chemicals killed residents and harm ...
starting in 1947 and uncontrolled
dumping in
Valley of the Drums – led to the
Superfund
Superfund is a United States federal environmental remediation program established by the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). The program is administered by the United States Environmental Pro ...
legislation of 1980. The pollution of industrial land gave rise to the name
brownfield
Brownfield is previously-developed land that has been abandoned or underused, and which may carry pollution, or a risk of pollution, from industrial use. The specific definition of brownfield land varies and is decided by policy makers and l ...
, a term now common in
city planning
Urban planning (also called city planning in some contexts) is the process of developing and designing land use and the built environment, including air, water, and the infrastructure passing into and out of urban areas, such as transportatio ...
.
The development of nuclear science introduced
radioactive contamination
Radioactive contamination, also called radiological pollution, is the deposition of, or presence of Radioactive decay, radioactive substances on surfaces or within solids, liquids, or gases (including the human body), where their presence is uni ...
, which can remain lethally radioactive for hundreds of thousands of years.
Lake Karachay – named by the
Worldwatch Institute
The Worldwatch Institute was a globally focused environmental research organization based in Washington, D.C., founded by Lester R. Brown. Worldwatch was named as one of the top ten sustainable development research organizations by Globescan S ...
as the "most polluted spot" on earth – served as a disposal site for the
Soviet Union
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
throughout the 1950s and 1960s.
Chelyabinsk
Chelyabinsk; , is the administrative center and largest types of inhabited localities in Russia, city of Chelyabinsk Oblast, Russia. It is the List of cities and towns in Russia by population, seventh-largest city in Russia, with a population ...
, Russia, is considered the "Most polluted place on the planet".
[Lenssen, "Nuclear Waste: The Problem that Won't Go Away", Worldwatch Institute, Washington, D.C., 1991: 15.]
Nuclear weapons
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either nuclear fission, fission (fission or atomic bomb) or a combination of fission and nuclear fusion, fusion reactions (thermonuclear weap ...
continued to be tested in the
Cold War
The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...
, especially in the earlier stages of their development. The toll on the worst-affected populations and the growth since then in understanding the critical threat to human health posed by
radioactivity
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ...
has also been a prohibitive complication associated with
nuclear power
Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by ...
. Though extreme care is practiced in that industry, the potential for disaster suggested by incidents such as those at
Three Mile Island,
Chernobyl
Chernobyl, officially called Chornobyl, is a partially abandoned city in Vyshhorod Raion, Kyiv Oblast, Ukraine. It is located within the Chernobyl Exclusion Zone, to the north of Kyiv and to the southwest of Gomel in neighbouring Belarus. ...
, and
Fukushima pose a lingering specter of public mistrust. Worldwide publicity has been intense on those disasters. Widespread support for
test ban treaties has ended almost all nuclear testing in the atmosphere.
International catastrophes such as the wreck of the
Amoco Cadiz
''Amoco Cadiz'' was an oil tanker owned by Amoco, Amoco Transport Corp and transporting crude oil for Royal Dutch Shell, Shell Oil. Operating under the Liberian flag, she ran aground on 16 March 1978 on Portsall, Portsall Rocks, from the coast ...
oil tanker off the coast of
Brittany
Brittany ( ) is a peninsula, historical country and cultural area in the north-west of modern France, covering the western part of what was known as Armorica in Roman Gaul. It became an Kingdom of Brittany, independent kingdom and then a Duch ...
in 1978 and the
Bhopal disaster
On 3 December 1984, over 500,000 people in the vicinity of the Union Carbide India Limited pesticide plant in Bhopal, Madhya Pradesh, India were exposed to the highly toxic gas methyl isocyanate, in what is considered the world's worst ind ...
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
Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes ...
. Most recently, the term
persistent organic pollutant
Persistent organic pollutants (POPs) are organic compounds that are resistant to degradation through chemical, biological, and photolytic processes. They are toxic and adversely affect human health and the environment around the world. Because ...
(POP) has come to describe a group of chemicals such as
PBDEs and
PFCs, among others. Though their effects remain poorly 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
Bioaccumulation is the gradual accumulation of substances, such as pesticides or other chemicals, in an organism. Bioaccumulation occurs when an organism absorbs a substance faster than it can be lost or eliminated by catabolism and excretion. T ...
after only a relatively brief period of widespread use.

The
Great Pacific Garbage Patch is a concentration of plastics in the
North Pacific Gyre. It and other garbage patches contain debris that can transport invasive species and that can entangle and be ingested by wildlife. Organizations such as
5 Gyres and the Algalita Marine Research Foundation have researched the Great Pacific Garbage Patch and found
microplastics
Microplastics are "synthetic solid particles or polymeric matrices, with regular or irregular shape and with size ranging from 1 μm to 5 mm, of either primary or secondary manufacturing origin, which are insoluble in water." Microplastics a ...
in the water.
Pollution introduced by light at night is becoming a global problem, more severe in urban centres, but contaminating also large territories, far away from towns.
Growing evidence of local and global pollution and an increasingly informed public over time have given rise to
environmentalism
Environmentalism is a broad philosophy, ideology, and social movement about supporting life, habitats, and surroundings. While environmentalism focuses more on the environmental and nature-related aspects of green ideology and politics, ecolog ...
and the
environmental movement
The environmental movement (sometimes referred to as the ecology movement) is a social movement that aims to protect the natural world from harmful environmental practices in order to create sustainable living. In its recognition of humanity a ...
, which generally seek to limit human impact on the environment.
See also
* Biological contamination
* Brain health and pollution
* Chemical hazards, Chemical contamination
* Environmental health
* Environmental racism
* Hazardous Substances Data Bank
* Human overpopulation, Overpopulation
* Neuroplastic effects of pollution
* Pollutant release and transfer register
* Polluter pays principle
* Pollution haven hypothesis
* Regulation of greenhouse gases under the Clean Air Act
* ''Max Liboiron, Pollution is Colonialism''
* Sacrifice zone
References
External links
OEHHA proposition 65 listNational Toxicology Program– from US National Institutes of Health. Reports and studies on how pollutants affect people
TOXNET– NIH databases and reports on toxicology
– Geographic Information System (GIS) that uses maps of the United States to help users visually explore data from the United States Environmental Protection Agency (EPA) Toxics Release Inventory and Superfund Basic Research Programs
EPA.gov– manages Superfund sites and the pollutants in them (CERCLA). Ma
the EPA SuperfundToxic Release Inventory– tracks how much waste US companies release into the water and air. Gives permits for releasing specific quantities of these pollutants each year.
– Top 20 pollutants, how they affect people, what US industries use them and the products in which they are found
Documentary Film by Sławomir Grünberg, Slawomir Grünberg (1996)
Nieman Reports , Tracking Toxics When the Data Are Polluted
{{Authority control
Pollution,
Environmental toxicology
Articles containing video clips