pollution pollution pollution is the introduction of contaminants into the natural environment that cause adverse change. pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. litter on the coast of guyana part of a series onpollutionair pollution from a factory air acid rain air quality index atmospheric dispersion modeling chlorofluorocarbon exhaust gas haze indoor air internal combustion engine global dimming global distillation ozone depletion particulates persistent organic pollutant smog aerosol soot volatile organic compound biological biological hazard genetic introduced species (invasive species) digital information electromagnetic light ecological overillumination radio spectrum natural ozone radium and radon in the environment volcanic ash wildfire noise transportation land water air rail sustainable transport urban sonar marine mammals and sonar industrial military abstract noise control radiation actinides bioremediation depleted uranium nuclear fission nuclear fallout plutonium poisoning radioactivity uranium electromagnetic radiation and health radioactive waste soil agricultural herbicides manure waste pesticides land degradation bioremediation defecation electrical resistance heating soil guideline values phytoremediation solid waste biodegradable waste brown waste electronic waste battery recycling food waste green waste hazardous waste biomedical waste chemical waste construction waste lead poisoning mercury poisoning toxic waste international waste industrial waste lead smelting litter mining coal mining gold mining surface mining deep sea mining mining waste uranium mining municipal solid waste garbage nanomaterials plastic microplastics packaging waste post-consumer waste waste management landfill thermal treatment space satellite thermal urban heat island visual air travel advertising clutter overhead power lines traffic signs vandalism war chemical warfare herbicidal warfare (agent orange) nuclear holocaust (nuclear fallout - nuclear famine - nuclear winter) scorched earth unexploded ordnance war and environmental law water agricultural wastewater diseases eutrophication firewater freshwater groundwater hypoxia industrial wastewater marine debris monitoring nonpoint source see misc section nutrient ocean acidification oil spill pharmaceuticals freshwater salinization septic tanks sewage septic tanks pit latrine shipping stagnation sulfur water surface runoff turbidity urban runoff water quality misc point source area source legacy pollution lists diseases law by country most polluted cities least polluted cities by pm2.5 treaties categories by country environment portal ecology portal although environmental pollution can be caused by natural events, the word pollution generally implies that the contaminants have an anthropogenic source – that is, a source created by human activities, such as manufacturing, extractive industries, poor waste management, transportation or agriculture. pollution is often classed as point source (coming from a highly concentrated specific site, such as a factory or mine) or nonpoint source pollution (coming from a widespread distributed sources, such as microplastics or agricultural runoff). many sources of pollution were unregulated parts of industrialization during the 19th and 20th centuries until the emergence of environmental regulation and pollution policy in the later half of the 20th century. sites where historically polluting industries released persistent pollutants may have legacy pollution long after the source of the pollution is stopped. major forms of pollution include air pollution, light pollution, litter, noise pollution, plastic pollution, soil contamination, radioactive contamination, thermal pollution, visual pollution, and water pollution. pollution has widespread consequence on human and environmental health, having systematic impact on social and economic systems. in 2015, pollution killed nine million people worldwide (one in six deaths). air pollution accounted for 3⁄4 of these earlier deaths. a 2022 literature survey found that levels of anthropogenic chemical pollution have exceeded planetary boundaries 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, and continues to be a core element of environmental conflicts, particularly in the global south. because of the impacts of these chemicals, local, country and international 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 is an important part of all of the sustainable development goals. definitions and types various definitions of pollution exist, which may or may not recognize certain types, such as noise pollution or greenhouse gases. 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 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."smog in the center of moscow, russia in august 2010 the major forms of pollution are listed below along with the particular contaminants relevant to each of them: air pollution: the release of chemicals and particulates into the atmosphere. common gaseous pollutants include carbon monoxide, sulfur dioxide, chlorofluorocarbons (cfcs) and nitrogen oxides produced by industry and motor vehicles. photochemical ozone and smog are created as nitrogen oxides and hydrocarbons react to sunlight. particulate matter, or fine dust is characterized by their micrometre size pm10 to pm2.5. electromagnetic pollution: the overabundance of electromagnetic radiation 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: includes light trespass, over-illumination and astronomical interference. littering: the criminal throwing of inappropriate man-made objects, unremoved, onto public and private properties. noise pollution: which encompasses roadway noise, aircraft noise, industrial noise as well as high-intensity sonar. plastic pollution: involves the accumulation of plastic products and microplastics in the environment that adversely affects wildlife, wildlife habitat, or humans. soil contamination occurs when chemicals are released by spill or underground leakage. among the most significant soil contaminants are hydrocarbons, heavy metals, mtbe, herbicides, pesticides and chlorinated hydrocarbons. radioactive contamination, resulting from 20th century activities in atomic physics, such as nuclear power generation and nuclear weapons research, manufacture and deployment. (see alpha emitters and actinides in the environment.) thermal pollution, is a temperature change in natural water bodies caused by human influence, such as use of water as coolant in a power plant. visual pollution, which can refer to the presence of overhead power lines, motorway billboards, scarred landforms (as from strip mining), open storage of trash, municipal solid waste or space debris. 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 and chemical contaminants, such as chlorine, from treated sewage; and releases of waste and contaminants into surface runoff 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). pollutants the lachine canal in montreal, quebec, canada blue drain and yellow fish symbol used by the uk environment agency to raise awareness of the ecological impacts of contaminating surface drainage this section is an excerpt from pollutant. surface runoff, also called nonpoint source pollution, from a farm field in iowa, the united states during a rainstorm. topsoil, as well as farm fertilizers and other potential pollutants, runoff unprotected farm fields when heavy rains occur. a pollutant or novel entity is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource. these can be both naturally forming (i.e. minerals or extracted compounds like oil) or anthropogenic in origin (i.e. manufactured materials or byproducts from biodegradation). pollutants result in environmental pollution or become public health concerns when they reach a concentration high enough to have significant negative impacts. a pollutant may cause long- or short-term damage by changing the growth rate of plant or animal species, or by interfering with human amenities, comfort, health, or property values. some pollutants are biodegradable and therefore will not persist in the environment in the long term. however, the degradation products of some pollutants are themselves polluting such as the products dde and ddd produced from the degradation of ddt. pollution has widespread negative impacts on the environment. when analyzed from a planetary boundaries perspective, human society has released novel entities that well exceed safe levels. natural causes one of the most significant natural sources of pollution are volcanoes, 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, hydrogen halides which can cause acid rain, sulfur dioxides, which are harmful to animals and damage the ozone layer, and hydrogen sulfides, 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, lead, and mercury. wildfires, which can be caused naturally by lightning strikes, 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 are one of the leading causes of air pollution. china, united states, russia, india mexico, and japan are the world leaders in air pollution emissions. principal stationary pollution sources include chemical plants, coal-fired power plants, oil refineries, petrochemical plants, nuclear waste disposal activity, incinerators, large livestock farms (dairy cows, pigs, poultry, etc.), pvc factories, metals production factories, plastics factories, and other heavy industry. agricultural air pollution comes from contemporary practices which include clear felling and burning of natural vegetation as well as spraying of pesticides and herbicides. about 400 million metric tons of hazardous wastes 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 co2, and generate approximately 30% of world's waste. in 2007, china overtook the united states as the world's biggest producer of co2, while still far behind based on per capita pollution (ranked 78th among the world's nations). an industrial area, with a power plant, south of yangzhou's downtown, china 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 landfills are the source of many chemical substances entering the soil environment (and often groundwater), emanating from the wide variety of refuse accepted, especially substances illegally discarded there, or from pre-1970 landfills that may have been subject to little control in the u.s. or eu. there have also been some unusual releases of polychlorinated dibenzodioxins, commonly called dioxins for simplicity, such as tcdd. 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. the motor vehicle is the most common cause of noise pollution, accounting for over 90% of all undesirable noise globally. plastic pollution it’s 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