States, air pollution problems were settled by litigation among the parties involved rather than by legislation. Definition of air pollution effects fine particulate matter pm2. It occurs in or near areas with a high traffic density and in the presence of specific climatic conditions no wind or weak winds, high temperatures, etc. An introduction to air pollution definitions, classifications, and. Air pollution occurs when harmful or excessive quantities of substances are introduced into earths atmosphere. These gases and particles known as pollutants tend to come from manmade.
Though, the output must be summarized and written in simpleformat english for easy understanding. Smoke pollution definition and meaning collins english. For example, photochemical smog is a typical form of pollution of all the main urban and industrial areas of the world. This definition implicitly acknowledges that some substances that are considered to be air pollutants are present naturally. Today, indoor air pollution caused by burning of traditional solid fuels such as woodfuel, agricultural residues, and dried animal dung in unvented cookstoves in rural areas of developing countries is not much different. Definitions and classifications used in the study of air pollution are. In the section of air pollution introduction, scientific definition, the explanation and description on causes and affects are the expected outcomes. The lar gest cause of air po llution in europe is ro ad transportation w ith o ver 5. Photochemical smog definition, air pollution containing ozone and other reactive chemical compounds formed by the action of sunlight on nitrogen oxides and hydrocarbons, especially those in automobile exhaust. At least two distinct types of smog are recognized.
Because we have given more than 30 ppt in one place. Start the pledge with we, the citizens of singapore, pledge to reduce pollution by 31. When a lowlevel inversion is coupled with stagnant winds and heavy local emissions of air contaminants, the conditions are right for an air pollution episode. Ground level ozone smog, commonly referred to as smog, is formed by a chemical reaction between volatile organic compounds vocs and nitrogen oxides nox in the presence of sunlight. Epa definition of pollution prevention memorandum pdf 4 pp, 27 k. The term smog was defined more than three decades ago to describe a. Air pollution consists of harmful or poisonous substances in outdoor or indoor air. Jul 21, 2019 smog is a visible form of air pollution that often appears as a thick haze. Smog is a term that refers to a combination of smoke and fog, but in modern times, smog refers mostly to groundlevel ozone o 3. Air pollution meaning in the cambridge english dictionary. Photochemical smog sulfur dioxide, nitrogen oxides, ozone and peroxyacl nitrates pans, give rise to photo chemical smog, irritates eyes and lungs. Epa information photochemical smog what it means for us.
The infamous london smog is an example of extreme air pollution. Smog is a kind of air pollution, originally named for the mixture of smoke and fog in the air. More than 7 million americans live in communities with unhealthy levels of air pollution. Photochemical smog happens when nitrogen oxides and volatile organic compounds react together in the presence of sunlight as a catalyst and form ozone at lower levels. Smog contains soot particulates like smoke, sulphur dioxide, nitrogen dioxide and other components. Chinese smog clean air for sale in china was the title of one of many recent news articles describing a doubledigit growth in the sale of air purifiers in china. Regions that experience higher levels of photochemical smog also observe higher corrosion rates in metallic structures that are situated outdoors. These are the problems more likely to be encountered by the primary health care provider. The word smog was coined in the early 20th century, and is a contraction portmanteau of the words smoke and fog to refer to smoky fog. Our information on local and state air pollution legislation in the u. In fact, breathing smoggy air can be hazardous because. Smog definition is a fog made heavier and darker by smoke and chemical fumes.
Shanghais smog is a mixture of pollution from coal, the primary source of energy for most homes and. It is considered to be a criteria pollutant in the tropospherethe lowermost layer of the atmospherebut not in the upper atmosphere, where it occurs naturally and serves to block harmful ultraviolet rays. Smog, soot, and other air pollution from transportation. Pdf pdear editor, recently many cities of pakistan have been struck by the havoc of smog. Consequences of air pollution co 2 is a good transmitter of sunlight, but it also partially restricts infrared radiation going back from the earth into space, which produces the socalled greenhouse effect that prevents a drastic cooling of the earth during the night increasing the amount of co 2 in the atmosphere. The term smog was first used around 1950 to describe the combination of smoke and fog in london. Air pollution is a global issue, it is a growing challenge since the time of industrialization and according to who ambient both urban and rural areas was estimated to cause 3. It is the contamination of air by harmful gases, dust and smoke which affects the plants, animals, and humans drastically. From smog hanging over cities to smoke inside the home, air pollution poses a major threat to health and climate. The vehicle retirement program and the welfare to work project are two new projects that have proven to be useful in the control of smog pollution in california. Air pollution in large industrial cities or urban regions is called smog.
The presence of a substance in the environment that because of its chemical composition or quantity prevents the. Primary and secondary pollutants a primary pollutant is an. Vocs are organic compounds that easily become vapors or gases, such as engine exhaust. Air pollution is a problem that greatly affects those living in large, urban centers and the third world. Smog is grimy, dirty, smelly and foul, it is more dangerous than smoke. Pdf air pollution sources, pollutants and mitigation. According to the california air resources board arb, part of the california environmental protection agency, many pollutants build up rapidly indoors, resulting in higher levels than usually found outside, especially in newer homes where tighter construction prevents. Indoor air pollution is when pollutants contaminate air indoors and is a very dangerous problem, claiming more than 2 million lives each year. History of air pollution legislation in the united states. Interactive qualifying project air pollution in asia.
Londontype smog occurs in the regions where 1 emission of the sulfurcontaining compounds is high due to burning of coal to generate heat and energy. The main sources of pollution affecting air quality in the adelaide metropolitan area are motor. Table i comes mainly from publications of the bureau of mines of the u. It can also damage other living organisms such as plants and animals by affecting the air quality and oxygen content of the air. Health effects of pollutants involved in photochemical smog. Air pollution definition, causes, effects and control. Air pollution in the united states has been well studied in the last 30 years.
Two common types of air pollutants that can reach unhealthy levels and affect lung health. Air pollution is harmful to people even if they do not have lung disease, but it is particularly dangerous for people living with asthma, copd, and other respiratory ailments. Photochemical smog refers to a type of air pollution that is generated when the suns ultraviolet rays react with nitrogen oxides in the earths atmosphere. It may cause diseases, allergies and even death to humans. Wood smoke in some new hampshire valley communities and locations near some high emitting residential sources increases exposure to particle pollution. During these hundred years, problem resolution was originally by private litigation to abate air pollution as a common law nuisance, either as a private nuisance, a public nuisance, or a trespass. Air pollution, facts and information national geographic. Also introduced are a brief history of air pollution. For the definition, it must be written thorough and detailed. The material contained in the chapter is divided into two sections. Air pollution is the presence of one or more disadvantageous content in such quantity and for such duration, as it is catastrophic, or tend to be catastrophic, to human health and welfare, animal or plant life.
Smogcausing pollutants are created by combustion, in particular from the burning of. Definition of outdoor air pollution ncbi bookshelf. The vehicle retirement program was designed by the bureau of automotive repair bar and offers california vehicle owners the opportunity to retire vehicles that fail a biennial smog. Indoor air pollution may arise from the use of open fires, unsafe fuels or combustion of biomass fuels, coal and kerosene. The major historical air pollution episodes all occurred during stagnant inversions in regions that had significant sources of combustion. Definition of outdoor air pollution outdoor air pollution. Air pollution refers to any physical, chemical or biological change in the air. The increase in the global concentrations of greenhouse gases co 2. Secondary pollutants, such as ozone, are formed when primary pollutants undergo chemical reactions in the atmosphere. Primary pollutants are emitted directly from a source, such as emissions of sulfur dioxide from coal combustion.
It is the contaminants of air by the discharge of detrimental substances. Air pollution can lead to disease and death in humans. Henry habicht then deputy administrator, m ay 28, 1992, explaining the agencys understanding and approach to pollution prevention. Although the term is derived from the words smoke and fog, it is often used to describe the pall of automotive or industrial origin that lies over many cities, and its composition is variable.
What you need to know about ozone and your health ozone, when it occurs at ground level, presents a serious air quality problem in many parts of the united states. When pollutants from the automobiles, factories etc. Although there are a number of important natural sources of air pollution including forest fires and volcanic eruptions, the term is usually. When inhaled even at very low levels ozone can cause a number of respiratory health effects. In other words, all manmade anthropogenic emissions into the air can be called air pollution, because they alter the chemical composition of the natural atmosphere. The tallest towers of shanghai, china, rise above the haze. An increase or decrease in the composition of these gases is harmful to. Frederick encyclopedia of life support systems eolss and surrounding areas. Pdf causes, consequences and control of air pollution. Photochemical smog an overview sciencedirect topics. The rain has a way of cleaning the dust and smog out of the air making things appear especially vivid and clear. In this case, the only pollutant emitted is co2, a greenhouse gas more on that later. Indoor air pollution refers to toxic contaminants that we encounter in our daily lives in our homes, schools and workplaces 1.
That day, the air took on a dusty, gray color and an acrid smell, and the city was covered in a layer of thick industrial smog. The definitions of chemical terms are largely in accordance. Fogs can be viewed as clouds that are in contact with. Most air pollution is from combustion internal combustion engines ice in transportation is one significant source source of smog pollutants ideally. Look toward the horizon during daylight hours, and you can see how much smog is in the air. Etiology can be difficult to establish because many signs and symptoms are nonspecific, making differential diagnosis a. Understanding air pollution respiratory health association. The primary object of this chapter is to introduce meteorological fundamentals related to the transport of air pollutants in the atmosphere. Sources of air pollution include gases such as ammonia, carbon monoxide, sulfur dioxide, nitrous oxides, methane and chlorofluorocarbons, particulates both organic and inorganic, and biological molecules. Smog formation in general relies on both primary and secondary pollutants. You may need a pdf reader to view some of the files on this page. Gas stoves or badly installed woodburning units with poor ventilation and maintenance can increase the indoor levels of carbon monoxide.
Air pollution is a mix of particles and gases that can reach harmful concentrations both outside and indoors. Originally the term smog meant a combination of smoke and fog, but it has recently. Today, it refers to a mixture of pollutants made up mostly of ground level ozone. He was president of the air pollution control association in 19751976. Haze is the reflection of sunlight off air pollution, while smog is what happens when pollution causes lowlying ozone. This is because the air becomes dirty contaminated or unclean. Atmospheric pollution, or air pollution, is the introduction of harmful particulates, biological molecules or chemical molecules into the earths atmosphere. Definitions and classifications used in the study of air pollution are introduced.
The nitrogen oxides come from vehicle exhausts, and volatile organic compounds come. Air pollution is used as a marker of sustainable development, as sources of air pollution also produce climatemodifying pollutants e. Smog is formed when pollutants like nitrogen oxide, carbon. Indoor air pollution has occurred since prehistoric times when people moved to live indoors and fire was brought into closed shelters for cooking and space heating 1. One could claim that air pollution started when humans began burning fuels. A key component of photochemical smog, ozone is formed by a complex reaction between nitrogen dioxide and hydrocarbons in the presence of sunlight. Pdf air pollution occurs when gases, dust particles, fumes or smoke or odour are introduced into the atmosphere in a way that makes it harmful to. The great smog of london in 1952 was one o f the wo rst air pollution events in history with over 8,000 deaths. Those affected by poor air quality can develop serious breathing and health problems such as asthma, chronic bronchitis, and even emphysema. Cars and trucks are major contributors to smog which is a serious health problem in central and eastern canada.
Air pollution emitted from transportation contributes to smog, and to poor air quality, which has negative impacts on the health and welfare of u. High concentrations of nitrogen oxides will often give the air a brownish tint. Classic smog results from large amounts of coal burning in an area and is caused by a mixture of. There is a certain percentage of gases present in the atmosphere. Policies to address air pollution also generate a range of benefits to human health, not only through air quality ted to household and ambient air pollution. Students develop an understanding of visible air pollutants with an incomplete combustion demonstration, a smog in a jar demonstration, building simple particulate matter collectors, and exploration of engineering roles related to air pollution. Many scientists believe that by reducing emissions from factories and vehicles, air quality can be. Smog in delhi is an ongoing severe air pollution event in new delhi and adjoining areas in the national capital territory of india.
The word was then intended to refer to what was sometimes known as pea soup fog, a familiar and serious problem in london from the 19th. Formatin and effects of smog encyclopedia of life support. Air pollution occurs when certain gases and particles build up in the atmosphere to such levels that they can cause harm to our health, causing breathing and respiratory problems, and even resulting in premature death, as well as damaging the environment around us. Chronic exposure of leaves and needles to air pollutants can also break down the waxy coating that helps prevent excessive water loss and damage from diseases, pests, drought and frost. The presence in the air of any air pollutant that reduces air quality enough to threaten the health and welfare or people, plants, and animals, to adversely affect materials and structures, andor to interfere with the enjoyment of life and property. Smoke and smog particle pollution and ozone nh des nh. What are the causes of air pollution pollutant description and main uk sources potential effects on healthenvironment particulate matter pmpm 10 and pm 2. Its effects can range from higher disease risks to rising temperatures. Health, earth science, experiential learning, geography, human geography. Consequences of air pollution co 2 is a good transmitter of sunlight, but it also partially restricts infrared radiation going back from the earth into space, which produces the socalled greenhouse effect that prevents a drastic cooling of the earth during the night.
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