With millions and millions of cars belching and spewing their toxic, gaseous fumes into the air everyday, and with countless refineries and manufacturing plants just adding to the problem, it is why LA has the most smog in the world.
Smog is a type of air pollution; the word "smog" was made in the early 20th century as a portmanteau of the words smoke and fog to refer to smoky fog. 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 century to the mid 20th century. This kind of smog is caused by the burning of large amounts of coal within a city; this smog contains soot particulates from smoke, sulfur dioxide and other components. Modern smog, as found for example in Los Angeles, is a type of air pollution derived from vehicular emission from internal combustion engines and industrial fumes that react in the atmosphere with sunlight to form secondary pollutants that also combine with the primary emissions to form photochemical smog. The atmospheric pollution levels of Los Angeles, Mexico City and other cities are increased by inversion that traps pollution close to the ground.
Coinage of the term "smog" is generally attributed to Dr. Henry Antoine Des Voeux in his 1905 paper, "Fog and Smoke" for a meeting of the Public Health Congress. The July 26, 1905 edition of the London newspaper Daily Graphic quoted Des Voeux, "He said it required no science to see that there was something produced in great cities which was not found in the country, and that was smoky fog, or what was known as 'smog.'" The following day the newspaper stated that "Dr. Des Voeux did a public service in coining a new word for the London fog." "Smog" also appears in a January 19, 1893, Los Angeles Times article and is attributed to "a witty English writer."
Photochemical smog was first described in the 1950s. It is the chemical reaction of sunlight, nitrogen oxides and volatile organic compounds in the atmosphere, which leaves airborne particles and ground-level ozone. This noxious mixture of air pollutants can include the following:
All of these chemicals are usually highly reactive and oxidizing. Photochemical smog is therefore considered to be a problem of modern industrialization. It is present in all modern cities, but it is more common in cities with sunny, warm, dry climates and a large number of motor vehicles. Because it travels with the wind, it can affect sparsely populated areas as well.
Smog is a serious problem in many cities and continues to harm human health. Ground-level ozone, sulfur dioxide, nitrogen dioxide and carbon monoxide are especially harmful for senior citizens, children, and people with heart and lung conditions such as emphysema, bronchitis, and asthma. It can inflame breathing passages, decrease the lungs' working capacity, cause shortness of breath, pain when inhaling deeply, wheezing, and coughing. It can cause eye and nose irritation and it dries out the protective membranes of the nose and throat and interferes with the body's ability to fight infection, increasing susceptibility to illness. Hospital admissions and respiratory deaths often increase during periods when ozone levels are high.
The U.S. EPA has developed an Air Quality Index to help explain air pollution levels to the general public. 8 hour average ozone concentrations of 85 to 104 ppbv are described as "Unhealthy for Sensitive Groups", 105 ppbv to 124 ppbv as "unhealthy" and 125 ppb to 404 ppb as "very unhealthy". The "very unhealthy" range for some other pollutants are: 355 μg m−3 - 424 μg m−3 for PM10; 15.5 ppm - 30.4ppm for CO and 0.65 ppm - 1.24 ppm for NO2.
The Ontario Medical Association announced that smog is responsible for an estimated 9,500 premature deaths in the province each year.
A 20-year American Cancer Society study found that cumulative exposure also increases the likelihood of premature death from a respiratory disease, implying the 8-hour standard may be insufficient.
According to an online 2013 MSN Healthy Living news story article by Robert Preidt, a study (featuring 806 women who had babies with birth defects between 1997 and 2006, and 849 women who had healthy babies) by lead author Amy Padula, a postdoctoral scholar in pediatrics at the Stanford University School of Medicine, smog in the San Joaquin Valley area of California was linked to two types of neural tube defects: spina bifida (a condition involving, among other manifestations, certain malformations of the spinal column), and anencephaly (the underdevelopment or absence of part or all of the brain, which if not fatal usually results in profound impairment).
Smog can form in almost any climate where industries or cities release large amounts of air pollution, such as smoke or gases. However, it is worse during periods of warmer, sunnier weather when the upper air is warm enough to inhibit vertical circulation. It is especially prevalent in geologic basins encircled by hills or mountains. It often stays for an extended period of time over densely populated cities or urban areas, and can build up to dangerous levels.
In 1306, concerns over air pollution were sufficient for Edward I to (briefly) ban coal fires in London. In 1661, John Evelyn's Fumifugium suggested burning fragrant wood instead of mineral coal, which he believed would reduce coughing. The Ballad of Gresham College the same year describes how the smoke "does our lungs and spirits choke, Our hanging spoil, and rust our iron."
Severe episodes of smog continued in the 19th and 20th centuries, mainly in the winter, and were nicknamed "pea-soupers". The Great Smog of 1952 darkened the streets of London and killed approximately 4,000 people in the short time of 4 days (a further 8,000 died from its effects in the following weeks and months). Initially a flu epidemic was blamed for the loss of life.
In 1956 the Clean Air Act started legally enforcing smokeless zones in the capital. There were areas where no soft coal was allowed to be burned in homes or in businesses, only coke, which produces no smoke. Because of the smokeless zones, reduced levels of sooty particulates made the intense and persistent London smog a thing of the past.
It was after this that the great clean-up of London began. One by one, historical buildings which, during the previous two centuries had gradually completely blackened externally, had their stone facades cleaned and restored to their original appearance. Victorian buildings whose appearance changed dramatically after cleaning included the British Museum of Natural History. A more recent example was the Palace of Westminster, which was cleaned in the 1980s. Smog caused by traffic pollution, however, does still occur in modern London.
Due to its location in a highland "bowl", cold air sinks down onto the urban area of Mexico City, trapping industrial and vehicle pollution underneath, and turning it into the most infamously smog-plagued city of Latin America. Within one generation, the city has changed from being known for some of the cleanest air of the world into one with some of the worst pollution, with pollutants like nitrogen dioxide being double or even triple international standards.
Similar to Mexico City, the air pollution of Santiago valley, located between the Andes and the Chilean Coast Range, turn it into the most infamously smog-plagued city of South America. Other aggravates of the situation reside in its high latitude (31 degrees South) and dry weather during most of the year.
In December 2005, schools and public offices had to close in Tehran, Iran and 1600 people were taken to hospital, in a severe smog blamed largely on unfiltered car exhaust.
Smog was brought to the attention of the general US public in 1933 with the publication of the book "Stop That Smoke", by Henry Obermeyer, a New York public utility official, in which he pointed out the effect on human life and even the destruction of 3,000 acres (12 km2) of a farmer's spinach crop. Since then, the United States Environmental Protection Agency has designated over 300 U.S. counties to be non-attainment areas for one or more pollutants tracked as part of the National Ambient Air Quality Standards. These areas are largely clustered around large metropolitan areas, with the largest contiguous non-attainment zones in California and the Northeast. Various U.S. and Canadian government agencies collaborate to produce real-time air quality maps and forecasts.
Because of their locations in low basins surrounded by mountains, Los Angeles and the San Joaquin Valley are notorious for their smog. The millions of vehicles in these regions combined with the additional effects of the San Francisco Bay and Los Angeles/Long Beach port complexes frequently contribute to further air pollution. While strict regulations by numerous California government agencies overseeing this problem have decreased the number of Stage 1 smog alerts from several hundred annually to just a few, these geologically predisposed entrapment zones collect pollution levels from cars, trucks and fixed sources which still exceeds health standards and is a pressing issue for the more than 25 million people who live there.
In the late 1990s, massive immigration to Ulaanbaatar from the countryside began. An estimated 150,000 households, mainly living in traditional Mongolian gers on the outskirts of Ulaanbaatar, burn wood and coal (some poor families burn even car tires and trash) to heat themselves during the harsh winter, which lasts from October to April, since these outskirts are not connected to the city's central heating system. A temporary solution to decrease smog was proposed in the form of stoves with improved efficiency, although with no visible results. Coal-fired ger stoves release high levels of ash and other particulate matter (PM). When inhaled, these particles can settle in the lungs and respiratory tract and cause health problems. At two to 10 times above Mongolian and international air quality standards, Ulaanbaatar's PM rates are among the worst in the world, according to a December 2009 World Bank report. The Asian Development Bank (ADB) estimates that health costs related to this air pollution account for as much as 4 percent of Mongolia's GDP.
Smog is a regular problem in Southeast Asia caused by land and forest fires in Indonesia, especially Sumatra and Kalimantan, although the term haze is preferred in describing the problem. Farmers and plantation owners are usually responsible for the fires, which they use to clear tracts of land for further plantings. Those fires mainly affect Brunei, Indonesia, Philippines, Malaysia, Singapore and Thailand, and occasionally Guam and Saipan. The economic losses of the fires in 1997 have been estimated at more than US$9 billion. This includes damages in agriculture production, destruction of forest lands, health, transportation, tourism, and other economic endeavours. Not included are social, environmental, and psychological problems and long-term health effects. The second-latest bout of haze to occur in Malaysia, Singapore and the Malacca Straits is in October 2006, and was caused by smoke from fires in Indonesia being blown across the Straits of Malacca by south-westerly winds. A similar haze has occurred in June 2013, with the PSI setting a new record in Singapore on June 21 at 12pm with a reading of 401, which is in the "Hazardous" range.
The Association of Southeast Asian Nations (ASEAN) reacted. In 2002, the Agreement on Transboundary Haze Pollution between all ASEAN nations. ASEAN formed a Regional Haze Action Plan (RHAP) and established a co-ordination and support unit (CSU). RHAP, with the help of Canada, established a monitoring and warning system for forest/vegetation fires and implemented a Fire Danger Rating System (FDRS). The Malaysian Meteorological Service (MMS) has issued a daily rating since September 2003. The Indonesians have been ineffective at enforcing legal policies on errant farmers.
An erupting volcano can also emit high levels of sulphur dioxide along with a large quantity of particulate matter; two key components to the creation of smog. However, the smog created as a result of a volcanic eruption is often known as vog to distinguish it as a natural occurrence.
The radiocarbon content of some plant life has been linked to the distribution of smog in some areas. For example; presence of Creosote bush in the Los Angeles area has been shown to have an effect on smog distribution that is more than fossil fuel combustion alone.
The severity of smog is often measured using automated optical instruments such as Nephelometers, as haze is associated with visibility and traffic control in ports. Haze however can also be an indication of poor air quality though this is often better reflected using accurate purpose built air indexes such as the American Air Quality Index, the Malaysian API (Air Pollution Index) and the Singaporean Pollutant Standards Index.
In hazy conditions, it is likely that the index will report the suspended particulate level. The disclosure of the responsible pollutant is mandated in some jurisdictions.
The Malaysian API does not have a capped value; hence its most hazardous readings can go above 500. Above 500, a state of emergency is declared in the affected area. Usually, this means that non-essential government services are suspended, and all ports in the affected area are closed. There may also be prohibitions on private sector commercial and industrial activities in the affected area excluding the food sector. So far, state of emergency rulings due to hazardous API levels were applied to the Malaysian towns of Port Klang, Kuala Selangor and the state of Sarawak during the 2005 Malaysian haze and the 1997 Southeast Asian haze.
−205.02 °C, 68 K, -337 °F
−191.5 °C, 82 K, -313 °F
(CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air. It is toxic to humans and animals when encountered in higher concentrations, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere it is spatially variable, short lived, having a role in the formation of ground-level ozone.
Carbon monoxide consists of one carbon atom and one oxygen atom, connected by a triple bond that consists of two covalent bonds as well as one dative covalent bond. It is the simplest oxocarbon, and isoelectronic with the cyanide ion and molecular nitrogen. In coordination complexes the carbon monoxide ligand is called carbonyl.
Carbon monoxide is produced from the partial oxidation of carbon-containing compounds; it forms when there is not enough oxygen to produce carbon dioxide (CO2
), such as when operating a stove or an internal combustion engine in an enclosed space. In the presence of oxygen, including atmospheric concentrations, carbon monoxide burns with a blue flame, producing carbon dioxide. Coal gas, which was widely used before the 1960s for domestic lighting, cooking, and heating, had carbon monoxide as a significant fuel constituent. Some processes in modern technology, such as iron smelting, still produce carbon monoxide as a byproduct.
Worldwide, the largest source of carbon monoxide is natural in origin, due to photochemical reactions in the troposphere that generate about 5 x 1012 kilograms per year. Other natural sources of CO include volcanoes, forest fires, and other forms of combustion.
In biology, carbon monoxide is naturally produced by the action of heme oxygenase 1 and 2 on the heme from hemoglobin breakdown. This process produces a certain amount of carboxyhemoglobin in normal persons, even if they do not breathe any carbon monoxide. Following the first report that carbon monoxide is a normal neurotransmitter in 1993, as well as one of three gases that naturally modulate inflammatory responses in the body (the other two being nitric oxide and hydrogen sulfide), carbon monoxide has received a great deal of clinical attention as a biological regulator. In many tissues, all three gases are known to act as anti-inflammatories, vasodilators, and promoters of neovascular growth. Clinical trials of small amounts of carbon monoxide as a drug are ongoing.
Aristotle (384–322 BC) first recorded that burning coals emanated toxic fumes. An ancient method of execution was to shut the criminal in a bathing room with smouldering coals. What was not known was the mechanism of death. Galen (129–199 AD) speculated that there was a change in the composition of the air that caused harm when inhaled. In 1776, the French chemist de Lassone produced CO by heating zinc oxide with coke, but mistakenly concluded that the gaseous product was hydrogen, as it burned with a blue flame. The gas was identified as a compound containing carbon and oxygen by the Scottish chemist William Cumberland Cruikshank in the year 1800. Its toxic properties on dogs were thoroughly investigated by Claude Bernard around 1846.
During World War II, a gas mixture including carbon monoxide was used to keep motor vehicles running in parts of the world where gasoline and diesel fuel were scarce. External (with a few exceptions) charcoal or wood gas generators were fitted, and the mixture of atmospheric nitrogen, carbon monoxide, and small amounts of other gases produced by gasification was piped to a gas mixer. The gas mixture produced by this process is known as wood gas. Carbon monoxide was also used on a small scale during the Holocaust at some Nazi extermination camps, the most notable by gas vans in Chelmno, and in the Action T4 "euthanasia" program.
Carbon monoxide has a molar mass of 28.0, which makes it slightly lighter than air, whose average molar mass is 28.8. According to the ideal gas law, CO is therefore less dense than air. Neither gas is "ideal", however, so neither exactly has the densities predicted by the ideal gas law.
The bond length between the carbon atom and the oxygen atom is 112.8 pm. This bond length is consistent with a triple bond, as in molecular nitrogen (N2
), which has a similar bond length and nearly the same molecular mass. Carbon–oxygen double bonds are significantly longer, 120.8 pm in formaldehyde, for example. The boiling point (82 K) and melting point (68 K) are very similar to those of N2
(77 K and 63 K, respectively). The bond dissociation energy of 1072 kJ/mol is stronger than that of N2
(942 kJ/mol) and represents the strongest chemical bond known.
The ground electronic state of carbon monoxide is a singlet state since there are no unpaired electrons.
Carbon and oxygen together have a total of 10 valence electrons in carbon monoxide. To satisfy the octet rule for the carbon, the two atoms form a triple bond, with six shared electrons in three bonding molecular orbitals, rather than the usual double bond found in organic carbonyl compounds. Since four of the shared electrons come from the oxygen atom and only two from carbon, one bonding orbital is occupied by two electrons from oxygen, forming a dative or dipolar bond. This causes a C ← O polarization of the molecule, with a small negative charge on carbon and a small positive charge on oxygen. The other two bonding orbitals are each occupied by one electron from carbon and one from oxygen, forming (polar) covalent bonds with a reverse C → O polarization, since oxygen is more electronegative than carbon. In the free carbon monoxide, a net negative charge δ- remains at the carbon end and the molecule has a small dipole moment of 0.122 D.
The molecule is therefore asymmetric: oxygen has more electron density than carbon, and is also slightly positively charged compared to carbon being negative. By contrast, the isoelectronic dinitrogen molecule has no dipole moment.
If carbon monoxide acts as a ligand, the polarity of the dipole may reverse with a net negative charge on the oxygen end, depending on the structure of the coordination complex. See also the section "Coordination chemistry"
Theoretical and experimental studies show that, despite the greater electronegativity of oxygen, the dipole moment points from the more-negative carbon end to the more-positive oxygen end. The three bonds are in fact polar covalent bonds that are strongly polarized. The calculated polarization toward the oxygen atom is 71% for the σ-bond and 77% for both π-bonds.
The oxidation state of carbon in carbon monoxide is +2 in each of these structures. It is calculated by counting all the bonding electrons as belonging to the more electronegative oxygen. Only the two non-bonding electrons on carbon are assigned to carbon. In this count, carbon then has only two valence electrons in the molecule compared to four in the free atom.
Carbon monoxide poisoning is the most common type of fatal air poisoning in many countries. Carbon monoxide is colourless, odorless, and tasteless, but highly toxic. It combines with hemoglobin to produce carboxyhemoglobin, which usurps the space in hemoglobin that normally carries oxygen, but is ineffective for delivering oxygen to bodily tissues. Concentrations as low as 667 ppm may cause up to 50% of the body's hemoglobin to convert to carboxyhemoglobin. A level of 50% carboxyhemoglobin may result in seizure, coma, and fatality. In the United States, the OSHA limits long-term workplace exposure levels above 50 ppm. Within short time scales, carbon monoxide absorption is cumulative, since the half-life is about 5 h in fresh air (see main article).
The most common symptoms of carbon monoxide poisoning may resemble other types of poisonings and infections, including symptoms such as headache, nausea, vomiting, dizziness, fatigue, and a feeling of weakness. Affected families often believe they are victims of food poisoning. Infants may be irritable and feed poorly. Neurological signs include confusion, disorientation, visual disturbance, syncope and seizures.
Some descriptions of carbon monoxide poisoning include retinal hemorrhages, and an abnormal cherry-red blood hue. In most clinical diagnoses these signs are seldom noticed. One difficulty with the usefulness of this cherry-red effect is that it corrects, or masks, what would otherwise be an unhealthy appearance, since the chief effect of removing deoxygenated hemoglobin is to make an asphyxiated person appear more normal, or a dead person appear more lifelike, similar to the effect of red colorants in embalming fluid. The "false" or unphysiologic red-coloring effect in anoxic CO-poisoned tissue is related to the meat-coloring commercial use of carbon monoxide, discussed below.
Carbon monoxide also binds to other molecules such as myoglobin and mitochondrial cytochrome oxidase. Exposures to carbon monoxide may cause significant damage to the heart and central nervous system, especially to the globus pallidus, often with long-term sequelae. Carbon monoxide may have severe adverse effects on the fetus of a pregnant woman.
Carbon monoxide is produced naturally by the human body as a signaling molecule. Thus, carbon monoxide may have a physiological role in the body, such as a neurotransmitter or a blood vessel relaxant. Because of carbon monoxide's role in the body, abnormalities in its metabolism have been linked to a variety of diseases, including neurodegenerations, hypertension, heart failure, and inflammation.
Carbon monoxide is a nutrient for methanogenic bacteria, a building-block for acetylcoenzyme A. This is the theme for the emerging field of bioorganometallic chemistry. Extremophile micro-organisms can, thus, metabolise carbon monoxide in such locations as the thermal vents of volcanoes.
In bacteria, carbon monoxide is produced via the reduction of carbon dioxide by the enzyme carbon monoxide dehydrogenase, an Fe-Ni-S-containing protein.
CooA is a carbon monoxide sensor protein. The scope of its biological role is still unknown; it may be part of a signaling pathway in bacteria and archaea. Its occurrence in mammals is not established.
Carbon monoxide occurs in various natural and artificial environments. Typical concentrations in parts per million are as follows:
Carbon monoxide is present in small amounts in the atmosphere, chiefly as a product of volcanic activity but also from natural and man-made fires (such as forest and bushfires, burning of crop residues, and sugarcane fire-cleaning). The burning of fossil fuels also contributes to carbon monoxide production. Carbon monoxide occurs dissolved in molten volcanic rock at high pressures in the Earth's mantle. Because natural sources of carbon monoxide are so variable from year to year, it is extremely difficult to accurately measure natural emissions of the gas.
Carbon monoxide has an indirect radiative forcing effect by elevating concentrations of methane and tropospheric ozone through chemical reactions with other atmospheric constituents (e.g., the hydroxyl radical, OH.
) that would otherwise destroy them. Through natural processes in the atmosphere, it is eventually oxidized to carbon dioxide. Carbon monoxide concentrations are both short-lived in the atmosphere and spatially variable.
In the atmosphere of Venus carbon monoxide occurs as a result of the photodissociation of carbon dioxide by electromagnetic radiation of wavelengths shorter than 169 nm.
Carbon monoxide is a temporary atmospheric pollutant in some urban areas, chiefly from the exhaust of internal combustion engines (including vehicles, portable and back-up generators, lawn mowers, power washers, etc.), but also from incomplete combustion of various other fuels (including wood, coal, charcoal, oil, paraffin, propane, natural gas, and trash).
Carbon monoxide is, along with aldehydes, part of the series of cycles of chemical reactions that form photochemical smog. It reacts with hydroxyl radical (•OH) to produce a radical intermediate •HOCO, which transfers rapidly its radical hydrogen to O2
to form peroxy radical (HO2
•) and carbon dioxide (CO2
). Peroxy radical subsequently reacts with nitrogen oxide (NO) to form nitrogen dioxide (NO2
) and hydroxyl radical. NO2
gives O(3P) via photolysis, thereby forming O3
following reaction with O2
. Since hydroxyl radical is formed during the formation of NO2
, the balance of the sequence of chemical reactions starting with carbon monoxide and leading to the formation of ozone is:
(where hν refers to the photon of light absorbed by the NO2
molecule in the sequence)
Although the creation of NO2
is the critical step leading to low level ozone formation, it also increases this ozone in another, somewhat mutually exclusive way, by reducing the quantity of NO that is available to react with ozone.
In closed environments, the concentration of carbon monoxide can easily rise to lethal levels. On average, 170 people in the United States die every year from carbon monoxide produced by non-automotive consumer products. However, according to the Florida Department of Health, "every year more than 500 Americans die from accidental exposure to carbon monoxide and thousands more across the U.S. require emergency medical care for non-fatal carbon monoxide poisoning" These products include malfunctioning fuel-burning appliances such as furnaces, ranges, water heaters, and gas and kerosene room heaters; engine-powered equipment such as portable generators; fireplaces; and charcoal that is burned in homes and other enclosed areas. The American Association of Poison Control Centers (AAPCC) reported 15,769 cases of carbon monoxide poisoning resulting in 39 deaths in 2007. In 2005, the CPSC reported 94 generator-related carbon monoxide poisoning deaths. Forty-seven of these deaths were known to have occurred during power outages due to severe weather, including Hurricane Katrina. Still others die from carbon monoxide produced by non-consumer products, such as cars left running in attached garages. The Centers for Disease Control and Prevention estimates that several thousand people go to hospital emergency rooms every year to be treated for carbon monoxide poisoning.
Carbon monoxide is absorbed through breathing and enters the blood stream through gas exchange in the lungs. Normal circulating levels in the blood are 0% to 3%, and are higher in smokers. Carbon monoxide levels cannot be assessed through a physical exam. Laboratory testing requires a blood sample (arterial or venous) and laboratory analysis on a CO-Oximeter. Additionally, a noninvasive carboxyhemoglobin (SpCO) test method from Pulse CO-Oximetry exists and has been validated compared to invasive methods.
Outside of Earth, carbon monoxide is the second-most common molecule in the interstellar medium, after molecular hydrogen. Because of its asymmetry, the carbon monoxide molecule produces far brighter spectral lines than the hydrogen molecule, making CO much easier to detect. Interstellar CO was first detected with radio telescopes in 1970. It is now the most commonly used tracer of molecular gas in general in the interstellar medium of galaxies, as molecular hydrogen can only be detected using ultraviolet light, which requires space telescopes. Carbon monoxide observations provide much of the information about the molecular clouds in which most stars form.
Many methods have been developed for carbon monoxide's production.
A major industrial source of CO is producer gas, a mixture containing mostly carbon monoxide and nitrogen, formed by combustion of carbon in air at high temperature when there is an excess of carbon. In an oven, air is passed through a bed of coke. The initially produced CO2
equilibrates with the remaining hot carbon to give CO. The reaction of CO2
with carbon to give CO is described as the Boudouard reaction. Above 800 °C, CO is the predominant product:
Another source is "water gas", a mixture of hydrogen and carbon monoxide produced via the endothermic reaction of steam and carbon:
Other similar "synthesis gases" can be obtained from natural gas and other fuels.
Carbon monoxide is also a byproduct of the reduction of metal oxide ores with carbon, shown in a simplified form as follows:
Since CO is a gas, the reduction process can be driven by heating, exploiting the positive (favorable) entropy of reaction. The Ellingham diagram shows that CO formation is favored over CO2
in high temperatures.
Carbon monoxide is conveniently produced in the laboratory by the dehydration of formic acid, for example with sulfuric acid. Another method is heating an intimate mixture of powdered zinc metal and calcium carbonate, which releases CO and leaves behind zinc oxide and calcium oxide:
Most metals form coordination complexes containing covalently attached carbon monoxide. Only metals in lower oxidation states will complex with carbon monoxide ligands. This is because there must be sufficient electron density to facilitate back-donation from the metal dxz
-orbital, to the π*molecular orbital from CO. The lone pair on the carbon atom in CO, also donates electron density to the dx²−y²
on the metal to form a sigma bond. This electron donation is also exhibited with the cis effect, or the labilization of CO ligands in the cis position. In nickel carbonyl, Ni(CO)4
forms by the direct combination of carbon monoxide and nickel metal at room temperature. For this reason, nickel in any tubing or part must not come into prolonged contact with carbon monoxide (corrosion). Nickel carbonyl decomposes readily back to Ni and CO upon contact with hot surfaces, and this method is used for the industrial purification of nickel in the Mond process.
In nickel carbonyl and other carbonyls, the electron pair on the carbon interacts with the metal; the carbon monoxide donates the electron pair to the metal. In these situations, carbon monoxide is called the carbonyl
ligand. One of the most important metal carbonyls is iron pentacarbonyl, Fe(CO)5
Many metal-CO complexes are prepared by decarbonylation of organic solvents, not from CO. For instance, iridium trichloride and triphenylphosphine react in boiling 2-methoxyethanol or DMF to afford 2
Metal carbonyls in coordination chemistry are usually studied using infrared spectroscopy.
In the presence of strong acids and water, carbon monoxide reacts with alkenes to form carboxylic acids in a process known as the Koch–Haaf reaction. In the Gattermann-Koch reaction, arenes are converted to benzaldehyde derivatives in the presence of 3
AlCl and HCl. Organolithium compounds (e.g. butyl lithium) react with carbon monoxide, but these reactions have little scientific use.
Although CO reacts with carbocations and carbanions, it is relatively nonreactive toward organic compounds without the intervention of metal catalysts.
With main group reagents, CO undergoes several noteworthy reactions. Chlorination of CO is the industrial route to the important compound phosgene. With borane CO forms an adduct, H3
BCO, which is isoelectronic with the acylium cation [H3
CCO]+. CO reacts with sodium to give products resulting from C-C coupling such as sodium acetylenediolate 2·. It reacts with molten potassium to give a mixture of an organometallic compound, potassium acetylenediolate 2·, potassium benzenehexolate 6 , and potassium rhodizonate 2·.
The compounds cyclohexanehexone or triquinoyl (C6
) and cyclopentanepentone or leuconic acid (C5
), which so far have been obtained only in trace amounts, can be regarded as polymers of carbon monoxide.
At pressures of over 5 gigapascals, carbon monoxide converts into a solid polymer of carbon and oxygen. This is metastable at atmospheric pressure but is a powerful explosive.
Carbon monoxide is an industrial gas that has many applications in bulk chemicals manufacturing. Large quantities of aldehydes are produced by the hydroformylation reaction of alkenes, carbon monoxide, and H2
. Hydroformylation is coupled to the Shell Higher Olefin Process to give precursors to detergents.
Phosgene, useful for preparing isocyanates, polycarbonates, and polyurethanes, is produced by passing purified carbon monoxide and chlorine gas through a bed of porous activated carbon, which serves as a catalyst. World production of this compound was estimated to be 2.74 million tonnes in 1989.
Methanol is produced by the hydrogenation of carbon monoxide. In a related reaction, the hydrogenation of carbon monoxide is coupled to C-C bond formation, as in the Fischer-Tropsch process where carbon monoxide is hydrogenated to liquid hydrocarbon fuels. This technology allows coal or biomass to be converted to diesel.
In the Monsanto process, carbon monoxide and methanol react in the presence of a homogeneous rhodium catalyst and hydroiodic acid to give acetic acid. This process is responsible for most of the industrial production of acetic acid.
An industrial scale use for pure carbon monoxide is purifying nickel in the Mond process.
Carbon monoxide is used in modified atmosphere packaging systems in the US, mainly with fresh meat products such as beef, pork, and fish to keep them looking fresh. The carbon monoxide combines with myoglobin to form carboxymyoglobin, a bright-cherry-red pigment. Carboxymyoglobin is more stable than the oxygenated form of myoglobin, oxymyoglobin, which can become oxidized to the brown pigment metmyoglobin. This stable red color can persist much longer than in normally packaged meat. Typical levels of carbon monoxide used in the facilities that use this process are between 0.4% to 0.5%.
The technology was first given "generally recognized as safe" (GRAS) status by the U.S. Food and Drug Administration (FDA) in 2002 for use as a secondary packaging system, and does not require labeling. In 2004 the FDA approved CO as primary packaging method, declaring that CO does not mask spoilage odor. Despite this ruling, the process remains controversial for fears that it masks spoilage. In 2007 a bill was introduced to the United States House of Representatives to label modified atmosphere carbon monoxide packaging as a color additive, but the bill died in subcommittee. The process is banned in many other countries, including Japan, Singapore, and the European Union.
In biology, carbon monoxide is naturally produced by the action of heme oxygenase 1 and 2 on the heme from hemoglobin breakdown. This process produces a certain amount of carboxyhemoglobin in normal persons, even if they do not breathe any carbon monoxide.
Following the first report that carbon monoxide is a normal neurotransmitter in 1993, as well as one of three gases that naturally modulate inflammatory responses in the body (the other two being nitric oxide and hydrogen sulfide), carbon monoxide has received a great deal of clinical attention as a biological regulator. In many tissues, all three gases are known to act as anti-inflammatories, vasodilators, and encouragers of neovascular growth. However, the issues are complex, as neovascular growth is not always beneficial, since it plays a role in tumor growth, and also the damage from wet
macular degeneration, a disease for which smoking (a major source of carbon monoxide in the blood, several times more than natural production) increases the risk from 4 to 6 times.
There is a theory that, in some nerve cell synapses, when long-term memories are being laid down, the receiving cell makes carbon monoxide, which back-transmits to the transmitting cell, telling it to transmit more readily in future. Some such nerve cells have been shown to contain guanylate cyclase, an enzyme that is activated by carbon monoxide.
Studies involving carbon monoxide have been conducted in many laboratories throughout the world for its anti-inflammatory and cytoprotective properties. These properties have potential to be used to prevent the development of a series of pathological conditions including ischemia reperfusion injury, transplant rejection, atherosclerosis, severe sepsis, severe malaria, or autoimmunity. Clinical tests involving humans have been performed, however the results have not yet been released.
Carbon monoxide has also been used as a lasing medium in high-powered infrared lasers.
anat (h/r/t/c/b/l/s/a)/phys (r)/devp/prot/nttr/nttm/ntrp
noco/auto/cong/tumr, sysi/epon, injr
proc, drug (N1B)
Air pollution is the introduction into the atmosphere of chemicals, particulates, or biological materials that cause discomfort, disease, or death to humans, damage other living organisms such as food crops, or damage the natural environment or built environment.
The atmosphere is a complex dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems.
Indoor air pollution (see Airlog) and urban air quality are listed as two of the World’s Worst Toxic Pollution Problems in the 2008 Blacksmith Institute World's Worst Polluted Places report.
A substance in the air that can be adverse to humans and the environment is known as an air pollutant. Pollutants can be in the form of solid particles, liquid droplets, or gases. In addition, they may be natural or man-made. Pollutants can be classified as primary or secondary. Usually, primary pollutants are directly produced from a process, such as ash from a volcanic eruption, the carbon monoxide gas from a motor vehicle exhaust or sulphur dioxide released from factories. Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact. An important example of a secondary pollutant is ground level ozone — one of the many secondary pollutants that make up photochemical smog. Some pollutants may be both primary and secondary: that is, they are both emitted directly and formed from other primary pollutants.
Major primary pollutants produced by human activity include:
Secondary pollutants include:
Minor air pollutants include:
Persistent organic pollutants (POPs) are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes. Because of this, they have been observed to persist in the environment, to be capable of long-range transport, bioaccumulate in human and animal tissue, biomagnify in food chains, and to have potential significant impacts on human health and the environment.
Sources of air pollution refers to the various locations, activities or factors which are responsible for the releasing of pollutants into the atmosphere. These sources can be classified into two major categories which are:
Anthropogenic sources (man-made sources) mostly related to burning different kinds of fuel
Air pollutant emission factors are representative values that people attempt to relate the quantity of a pollutant released to the ambient air with an activity associated with the release of that pollutant. These factors are usually expressed as the weight of pollutant divided by a unit weight, volume, distance, or duration of the activity emitting the pollutant (e.g., kilograms of particulate emitted per tonne of coal burned). Such factors facilitate estimation of emissions from various sources of air pollution. In most cases, these factors are simply averages of all available data of acceptable quality, and are generally assumed to be representative of long-term averages.
There are 12 compounds in the list of POPs. Dioxins and furans are two of them and are intentionally created by combustion of organics, like open burning of plastics. The POPs are also endocrine disruptor and can mutate the human genes.
The United States Environmental Protection Agency has published a compilation of air pollutant emission factors for a multitude of industrial sources. The United Kingdom, Australia, Canada and many other countries have published similar compilations, as well as the European Environment Agency.
A lack of ventilation indoors concentrates air pollution where people often spend the majority of their time. Radon (Rn) gas, a carcinogen, is exuded from the Earth in certain locations and trapped inside houses. Building materials including carpeting and plywood emit formaldehyde (H2CO) gas. Paint and solvents give off volatile organic compounds (VOCs) as they dry. Lead paint can degenerate into dust and be inhaled. Intentional air pollution is introduced with the use of air fresheners, incense, and other scented items. Controlled wood fires in stoves and fireplaces can add significant amounts of smoke particulates into the air, inside and out. Indoor pollution fatalities may be caused by using pesticides and other chemical sprays indoors without proper ventilation.
Carbon monoxide (CO) poisoning and fatalities are often caused by faulty vents and chimneys, or by the burning of charcoal indoors. Chronic carbon monoxide poisoning can result even from poorly adjusted pilot lights. Traps are built into all domestic plumbing to keep sewer gas and hydrogen sulfide, out of interiors. Clothing emits tetrachloroethylene, or other dry cleaning fluids, for days after dry cleaning.
Though its use has now been banned in many countries, the extensive use of asbestos in industrial and domestic environments in the past has left a potentially very dangerous material in many localities. Asbestosis is a chronic inflammatory medical condition affecting the tissue of the lungs. It occurs after long-term, heavy exposure to asbestos from asbestos-containing materials in structures. Sufferers have severe dyspnea (shortness of breath) and are at an increased risk regarding several different types of lung cancer. As clear explanations are not always stressed in non-technical literature, care should be taken to distinguish between several forms of relevant diseases. According to the World Health Organisation (WHO), these may defined as; asbestosis, lung cancer, and Peritoneal Mesothelioma (generally a very rare form of cancer, when more widespread it is almost always associated with prolonged exposure to asbestos).
Biological sources of air pollution are also found indoors, as gases and airborne particulates. Pets produce dander, people produce dust from minute skin flakes and decomposed hair, dust mites in bedding, carpeting and furniture produce enzymes and micrometre-sized fecal droppings, inhabitants emit methane, mold forms in walls and generates mycotoxins and spores, air conditioning systems can incubate Legionnaires' disease and mold, and houseplants, soil and surrounding gardens can produce pollen, dust, and mold. Indoors, the lack of air circulation allows these airborne pollutants to accumulate more than they would otherwise occur in nature.
Air pollution is a significant risk factor for multiple health conditions including respiratory infections, heart disease, and lung cancer, according to the WHO. The health effects caused by air pollution may include difficulty in breathing, wheezing, coughing, asthma and aggravation of existing respiratory and cardiac conditions. These effects can result in increased medication use, increased doctor or emergency room visits, more hospital admissions and premature death. The human health effects of poor air quality are far reaching, but principally affect the body's respiratory system and the cardiovascular system. Individual reactions to air pollutants depend on the type of pollutant a person is exposed to, the degree of exposure, the individual's health status and genetics.][
The most common sources of air pollution include particulates, ozone, nitrogen dioxide, and sulfur dioxide. Both indoor and outdoor air pollution have caused approximately 3.3 million deaths worldwide. Children aged less than five years that live in developing countries are the most vulnerable population in terms of total deaths attributable to indoor and outdoor air pollution.
The World Health Organization states that 2.4 million people die each year from causes directly attributable to air pollution, with 1.5 million of these deaths attributable to indoor air pollution. "Epidemiological studies suggest that more than 500,000 Americans die each year from cardiopulmonary disease linked to breathing fine particle air pollution. . ." A study by the University of Birmingham has shown a strong correlation between pneumonia related deaths and air pollution from motor vehicles. Worldwide more deaths per year are linked to air pollution than to automobile accidents. A 2005 study by the European Commission calculated that air pollution reduces life expectancy by an average of almost nine months across the European Union. Causes of deaths include aggravated asthma, emphysema, lung and heart diseases, and respiratory allergies. The US EPA estimates that a proposed set of changes in diesel engine technology (Tier 2) could result in 12,000 fewer premature mortalities, 15,000 fewer heart attacks, 6,000 fewer emergency room visits by children with asthma, and 8,900 fewer respiratory-related hospital admissions each year in the United States.][
The US EPA estimates allowing a ground-level ozone concentration of 65 parts per billion, would avert 1,700 to 5,100 premature deaths nationwide in 2020 compared with the current 75-ppb standard. The agency projects the stricter standard would also prevent an additional 26,000 cases of aggravated asthma, and more than a million cases of missed work or school.
The worst short term civilian pollution crisis in India was the 1984 Bhopal Disaster. Leaked industrial vapours from the Union Carbide factory, belonging to Union Carbide, Inc., U.S.A., killed more than 25,000 people outright and injured anywhere from 150,000 to 600,000. The United Kingdom suffered its worst air pollution event when the December 4 Great Smog of 1952 formed over London. In six days more than 4,000 died, and 8,000 more died within the following months.][ An accidental leak of anthrax spores from a biological warfare laboratory in the former USSR in 1979 near Sverdlovsk is believed to have been the cause of hundreds of civilian deaths.][ The worst single incident of air pollution to occur in the US occurred in Donora, Pennsylvania in late October, 1948, when 20 people died and over 7,000 were injured.
A new economic study of the health impacts and associated costs of air pollution in the Los Angeles Basin and San Joaquin Valley of Southern California shows that more than 3800 people die prematurely (approximately 14 years earlier than normal) each year because air pollution levels violate federal standards. The number of annual premature deaths is considerably higher than the fatalities related to auto collisions in the same area, which average fewer than 2,000 per year.
Diesel exhaust (DE) is a major contributor to combustion derived particulate matter air pollution. In several human experimental studies, using a well validated exposure chamber setup, DE has been linked to acute vascular dysfunction and increased thrombus formation. This serves as a plausible mechanistic link between the previously described association between particulates air pollution and increased cardiovascular morbidity and mortality.
A 2007 review of evidence found ambient air pollution exposure is a risk factor correlating with increased total mortality from cardiovascular events (range: 12% to 14% per a 10 microg/m3 increase). PMID 19235364.
Air pollution is also emerging as a risk factor for stroke, particularly in developing countries where pollutant levels are highest. A 2007 study found that in women air pollution is associated not with hemorrhagic but with ischemic stroke. Air pollution was also found to be associated with increased incidence and mortality from coronary stroke in a cohort study in 2011. Associations are believed to be causal and effects may be mediated by vasoconstriction, low-grade inflammation or autonomic nervous system imbalance or other mechanisms.
A study from around the years of 1999 to 2000, by the University of Washington, showed that patients near and around particulates air pollution had an increased risk of pulmonary exacerbations and decrease in lung function. Patients were examined before the study for amounts of specific pollutants like Pseudomonas aeruginosa or Burkholderia cenocepacia as well as their socioeconomic standing. Participants involved in the study were located in the United States in close proximity to an Environmental Protection Agency.][ During the time of the study 117 deaths were associated with air pollution. Many patients in the study lived in or near large metropolitan areas in order to be close to medical help. These same patients had higher level of pollutants found in their system because of more emissions in larger cities. As cystic fibrosis patients already suffer from decreased lung function, everyday pollutants such as smoke, emissions from automobiles, tobacco smoke and improper use of indoor heating devices could further compromise lung function.
Chronic obstructive pulmonary disease (COPD) includes diseases such as chronic bronchitis and emphysema.
Researches have demonstrated increased risk of developing asthma and COPD from increased exposure to traffic-related air pollution. Additionally, air pollution has been associated with increased hosptializations and mortality from asthma and COPD.
A study conducted in 1960-1961 in the wake of the Great Smog of 1952 compared 293 London residents with 477 residents of Gloucester, Peterborough, and Norwich, three towns with low reported death rates from chronic bronchitis. All subjects were male postal truck drivers aged 40 to 59. Compared to the subjects from the outlying towns, the London subjects exhibited more severe respiratory symptoms (including cough, phlegm, and dyspnea), reduced lung function (1FEV and peak flow rate), and increased sputum production and purulence. The differences were more pronounced for subjects aged 50 to 59. The study controlled for age and smoking habits, so concluded that air pollution was the most likely cause of the observed differences.
It is believed that much like cystic fibrosis, by living in a more urban environment serious health hazards become more apparent. Studies have shown that in urban areas patients suffer mucus hypersecretion, lower levels of lung function, and more self diagnosis of chronic bronchitis and emphysema.
A review of evidence regarding whether ambient air pollution exposure is a risk factor for cancer in 2007 found solid data to conclude that long-term exposure to PM2.5 (fine particulates) increases the overall risk of nonaccidental mortality by 6% per a 10 microg/m3 increase.PMID 19235364
The review further noted that living close to busy traffic appears to be associated with elevated risks of these three outcomes (increase in lung cancer deaths, cardiovascular deaths, and overall nonaccidental deaths. PMID 19235364
The reviewers also found suggestive evidence that exposure to PM2.5 is positively associated with mortality from coronary heart diseases and exposure to SO2 increases mortality from lung cancer, but the data was insufficient to provide solid conclusions.
In 2011, a large Danish epidemiological study found an increased risk of lung cancer for patients who lived in areas with high nitrogen oxide concentrations. In this study, the association was higher for non-smokers than smokers. An additional Danish study, also in 2011, likewise noted evidence of possible associations between air pollution and other forms of cancer, including cervical cancer and brain cancer.
Around the world, children living in cities with high exposure to air pollutants are at increased risk of developing asthma, pneumonia and other lower respiratory infections. Because children are outdoors more and have higher minute ventilation they are more susceptible to the dangers of air pollution. Risks of low initial birth weight are also heightened in such cities.
The World Health Organization reports that the greatest concentrations of particulates are found in countries with low economic world power and high poverty and population growth rates. Examples of these countries include Egypt, Sudan, Mongolia, and Indonesia. However even in the United States, despite the passage of the Clean Air Act in 1970, in 2002 at least 146 million Americans were living in non-attainment areas—regions in which the concentration of certain air pollutants exceeded federal standards. These dangerous pollutants are known as the criteria pollutants, and include ozone, particulates, sulfur dioxide, nitrogen dioxide, carbon monoxide, and lead. Protective measures to ensure children's health are being taken in cities such as New Delhi, India where buses now use compressed natural gas to help eliminate the "pea-soup" smog.
Even in the areas with relatively low levels of air pollution, public health effects can be significant and costly, since a large number of people breathe in such pollutants. A 2005 scientific study for the British Columbia Lung Association showed that a small improvement in air quality (1% reduction of ambient PM2.5 and ozone concentrations) would produce a $29 million in annual savings in the Metro Vancouver region in 2010. This finding is based on health valuation of lethal (death) and sub-lethal (illness) effects.
There are various air pollution control technologies and land use planning strategies available to reduce air pollution. At its most basic level land use planning is likely to involve zoning and transport infrastructure planning. In most developed countries, land use planning is an important part of social policy, ensuring that land is used efficiently for the benefit of the wider economy and population as well as to protect the environment.
Efforts to reduce pollution from mobile sources includes primary regulation (many developing countries have permissive regulations),][ expanding regulation to new sources (such as cruise and transport ships, farm equipment, and small gas-powered equipment such as lawn trimmers, chainsaws, and snowmobiles), increased fuel efficiency (such as through the use of hybrid vehicles), conversion to cleaner fuels (such as bioethanol, biodiesel, or conversion to electric vehicles).
The following items are commonly used as pollution control devices by industry or transportation devices. They can either destroy contaminants or remove them from an exhaust stream before it is emitted into the atmosphere.
In general, there are two types of air quality standards. The first class of standards (such as the U.S. National Ambient Air Quality Standards and E.U. Air Quality Directive) set maximum atmospheric concentrations for specific pollutants. Environmental agencies enact regulations which are intended to result in attainment of these target levels. The second class (such as the North American Air Quality Index) take the form of a scale with various thresholds, which is used to communicate to the public the relative risk of outdoor activity. The scale may or may not distinguish between different pollutants.
In Canada air pollution and associated health risks are measured with the The Air Quality Health Index or (AQHI). It is a health protection tool used to make decisions to reduce short-term exposure to air pollution by adjusting activity levels during increased levels of air pollution.
The Air Quality Health Index or "AQHI" is a federal program jointly coordinated by Health Canada and Environment Canada. However, the AQHI program would not be possible without the commitment and support of the provinces, municipalities and NGOs. From air quality monitoring to health risk communication and community engagement, local partners are responsible for the vast majority of work related to AQHI implementation. The AQHI provides a number from 1 to 10+ to indicate the level of health risk associated with local air quality. Occasionally, when the amount of air pollution is abnormally high, the number may exceed 10. The AQHI provides a local air quality current value as well as a local air quality maximums forecast for today, tonight and tomorrow and provides associated health advice.
As it is now known that even low levels of air pollution can trigger discomfort for the sensitive population, the index has been developed as a continuum: The higher the number, the greater the health risk and need to take precautions. The index describes the level of health risk associated with this number as ‘low’, ‘moderate’, ‘high’ or ‘very high’, and suggests steps that can be taken to reduce exposure.
It is measured based on the observed relationship of Nitrogen Dioxide (NO2), ground-level Ozone (O3) and particulates (PM2.5) with mortality from an analysis of several Canadian cities. Significantly, all three of these pollutants can pose health risks, even at low levels of exposure, especially among those with pre-existing health problems.
When developing the AQHI, Health Canada’s original analysis of health effects included five major air pollutants: particulates, ozone, and nitrogen dioxide (NO2), as well as sulfur dioxide (SO2), and carbon monoxide (CO). The latter two pollutants provided little information in predicting health effects and were removed from the AQHI formulation.
The AQHI does not measure the effects of odour, pollen, dust, heat or humidity.
TA Luft is the German air quality regime.
Air pollution is usually concentrated in densely populated metropolitan areas, especially in developing countries where environmental regulations are relatively lax or nonexistent][. However, even populated areas in developed countries attain unhealthy levels of pollution with Los Angeles and Rome being two good examples.
The National-Scale Air Toxics Assessment (NATA) is EPA's ongoing comprehensive evaluation of air toxics in the U.S. EPA developed the NATA as a state-of-the-science screening tool for State/Local/Tribal Agencies to prioritize pollutants, emission sources and locations of interest for further study in order to gain a better understanding of risks. NATA assessments do not incorporate refined information about emission sources, but rather, use general information about sources to develop estimates of risks which are more likely to overestimate impacts than underestimate them. NATA provides estimates of the risk of cancer and other serious health effects from breathing (inhaling) air toxics in order to inform both national and more localized efforts to identify and prioritize air toxics, emission source types and locations which are of greatest potential concern in terms of contributing to population risk. This in turn helps air pollution experts focus limited analytical resources on areas and or populations where the potential for health risks are highest. Assessments include estimates of cancer and non-cancer health effects based on chronic exposure from outdoor sources, including assessments of non-cancer health effects for Diesel Particulate Matter (PM). Assessments provide a snapshot of the outdoor air quality and the risks to human health that would result if air toxic emissions levels remained unchanged.
In Europe, Council Directive 96/62/EC on ambient air quality assessment and management provides a common strategy against which member states can "set objectives for ambient air quality in order to avoid, prevent or reduce harmful effects on human health and the environment . . . and improve air quality where it is unsatisfactory".
On 25 July 2008 in the case Dieter Janecek v Freistaat Bayern CURIA, the European Court of Justice ruled that under this directive citizens have the right to require national authorities to implement a short term action plan that aims to maintain or achieve compliance to air quality limit values.
This important case law appears to confirm the role of the EC as centralised regulator to European nation-states as regards air pollution control. It places a supranational legal obligation on the UK to protect its citizens from dangerous levels of air pollution, furthermore superseding national interests with those of the citizen.
In 2010, the European Commission (EC) threatened the UK with legal action against the successive breaching of PM10 limit values. The UK government has identified that if fines are imposed, they could cost the nation upwards of £300 million per year.
In March 2011, the City of London remains the only UK region in breach of the EC’s limit values, and has been given 3 months to implement an emergency action plan aimed at meeting the EU Air Quality Directive. The City of London has dangerous levels of PM10 concentrations, estimated to cause 3000 deaths per year within the city. As well as the threat of EU fines, in 2010 it was threatened with legal action for scrapping the western congestion charge zone, which is claimed to have led to an increase in air pollution levels.
In response to these charges, Boris Johnson, Mayor of London, has criticised the current need for European cities to communicate with Europe through their nation state’s central government, arguing that in future "A great city like London" should be permitted to bypass its government and deal directly with the European Commission regarding its air quality action plan.
In part, this is an attempt to divert blame away from the Mayor's office, but it can also be interpreted as recognition that cities can transcend the traditional national government organisational hierarchy and develop solutions to air pollution using global governance networks, for example through transnational relations. Transnational relations include but are not exclusive to national governments and intergovernmental organisations allowing sub-national actors including cities and regions to partake in air pollution control as independent actors.
Particularly promising at present are global city partnerships. These can be built into networks, for example the C40 network, of which London is a member. The C40 is a public ‘non-state’ network of the world’s leading cities that aims to curb their greenhouse emissions. The C40 has been identified as ‘governance from the middle’ and is an alternative to intergovernmental policy. It has the potential to improve urban air quality as participating cities "exchange information, learn from best practices and consequently mitigate carbon dioxide emissions independently from national government decisions". A criticism of the C40 network is that its exclusive nature limits influence to participating cities and risks drawing resources away from less powerful city and regional actors.
The basic technology for analyzing air pollution is through the use of a variety of mathematical models for predicting the transport of air pollutants in the lower atmosphere. The principal methodologies are:
The point source problem is the best understood, since it involves simpler mathematics and has been studied for a long period of time, dating back to about the year 1900. It uses a Gaussian dispersion model for continuous buoyant pollution plumes to predict the air pollution isopleths, with consideration given to wind velocity, stack height, emission rate and stability class (a measure of atmospheric turbulence). This model has been extensively validated and calibrated with experimental data for all sorts of atmospheric conditions.
The roadway air dispersion model was developed starting in the late 1950s and early 1960s in response to requirements of the National Environmental Policy Act and the U.S. Department of Transportation (then known as the Federal Highway Administration) to understand impacts of proposed new highways upon air quality, especially in urban areas. Several research groups were active in this model development, among which were: the Environmental Research and Technology (ERT) group in Lexington, Massachusetts, the ESL Inc. group in Sunnyvale, California and the California Air Resources Board group in Sacramento, California. The research of the ESL group received a boost with a contract award from the United States Environmental Protection Agency to validate a line source model using sulfur hexafluoride as a tracer gas. This program was successful in validating the line source model developed by ESL Inc. Some of the earliest uses of the model were in court cases involving highway air pollution, the Arlington, Virginia portion of Interstate 66 and the New Jersey Turnpike widening project through East Brunswick, New Jersey.
Area source models were developed in 1971 through 1974 by the ERT and ESL groups, but addressed a smaller fraction of total air pollution emissions, so that their use and need was not as widespread as the line source model, which enjoyed hundreds of different applications as early as the 1970s. Similarly photochemical models were developed primarily in the 1960s and 1970s, but their use was more specialized and for regional needs, such as understanding smog formation in Los Angeles, California.
Pea soup, or a pea souper, also known as a black fog or killer fog, is a very thick and often yellowish, greenish, or blackish smog, caused by air pollution that contains soot particulates and the poisonous gas sulfur dioxide. These very thick smogs occur in cities and are derived from the smoke given off by the burning of soft coal for home heating and in industrial processes. Smog of this intensity is often lethal to vulnerable people such as the elderly, the very young and those with respiratory problems.
Such fogs were prevalent in UK cities, especially London where the smoke from millions of chimneys combined with the mists and fogs of the Thames valley. The result was commonly known as a London particular or London fog, which then, in a reversal of the idiom, became the name for a thick pea and ham soup.
An 1871 New York Times article refers to "London, particularly, where the population are periodically submerged in a fog of the consistency of pea soup..." The fogs caused large numbers of deaths from respiratory problems.
The worst recorded instance was the Great Smog of 1952, when 4,000 additional deaths were reported in the city over a couple of days, leading to the passage of the Clean Air Act 1956 which banned the use of coal for domestic fires in urban areas. The overall death toll from that incident is now believed to be around 12,000.
Contrary to popular impression, the Arthur Conan Doyle Sherlock Holmes stories contain only a handful of references to London fogs, and the phrase "pea-soup" is not used. A Study in Scarlet (1887) mentions that "a dun-coloured veil hung over the house-tops." The Adventure of the Bruce-Partington Plans (1912) describes "a dense yellow fog" that has settled down over London, and later notes, "a greasy, heavy brown swirl still drifting past us and condensing in oily drops on the windowpane".
In Chapter 3 of Charles Dickens' Bleak House, when Esther arrives in London, she asks of the person meeting her, "whether there was a great fire anywhere? For the streets were so full of dense brown smoke that scarcely anything was to be seen. 'O, dear no, miss,' he said. 'This is a London particular.' I had never heard of such a thing. 'A fog, miss,' said the young gentleman."
In the phrase "pea-soup fog," the implied comparison may have been to yellow pea soup: "...the yellow fog hung so thick and heavy in the streets of London that the lamps were lighted" (Frances Hodgson Burnett, A Little Princess, 1892); "The yellow fog that rubs its back upon the window-panes," (T. S. Eliot, The Love Song of J. Alfred Prufrock, 1917); "London had been reeking in a green-yellow fog" (Winston Churchill, A Traveller in War-Time, 1918); "the brown fog of a winter dawn" (T. S. Eliot, The Waste Land (1922); "a faint yellow fog" (Stella Benson, This is the End). Inez Haynes Irwin, writing in The Californiacs (1921), praises what was then the superior quality of California fog, saying it is "Not distilled from pea soup like the London fogs; moist air-gauzes rather, pearl-touched and glimmering."
In the animated television Christmas feature Rudolph the Red-Nosed Reindeer (1964), the characters Rudolph, Hermey and Yukon Cornelius are travelling through a thick fog when the following exchange takes place: Yukon Cornelius: "This fog's as thick as peanut butter!" Hermey: "You mean pea soup." Yukon Cornelius: "You eat what you like, and I'll eat what I like!"
In the book Un Lun Dun by China Miéville, the London Fog takes on the role of villain: the "Smog" of UnLondon. The Clean Air Act is mistranslated as the Klinneract.
Also, in the book The Woman in Black by Susan Hill, the second chapter is entitled "A London Particular" and mentions the thick, dense fog of London, which Arthur Kipps witnesses on his journey to work at his solicitors' office.
The Smog Check Program has greatly reduced air pollution created by millions of cars in California. According to the California Air Resources Board, the program removes about 400 tons of smog-forming pollutants from California’s air every day. (smogcheck.ca.gov) Diesel and other gross polluting vehicle's are still allowed to be on the road. They do not require smog tests. Unless the auto industry helps subsidize bio-diesel, even California's tough standards on emissions may not be enough to curb automobile pollution. There are about 572,000 registered diesel vehicles in California. Diesel by far out paces gas in emissions. Up to about 15 times greater pollution than gas vehicles. The program is highly successful. It requires owners of older vehicles to inspect their emission system before being allowed to re-register. There is a misconception that California drivers wait until the last minute to smog. This is false, as you are required to do so before they mail you a sticker. Also, if there are any issues, they need to be corrected. Which cant be done at a test station. Most people smog as early as possible to receive their sticker on time. You can pay registration as soon as possible to avoid late fees.
California's automobile emission standards are among the highest in the world.][ In 1996, California's government sought to enforce stricter Smog Check tests because the more populated areas of the state were heavily polluting. The state][ figured that if they zeroed in on the very populated areas of the state, there would be a significant reduction in car emissions air polluting. The government also decided that since some areas needed more attention than others in relation to smog checks, those areas were to have stricter test/ smog laws then others. While inspecting cars for smog, the state recognized the fact that 10-15% of the states smog was coming from the emissions of large cars with large engines. SUV's put out 43% more global-warming pollutants. This led to truck owners being closely zeroed in on for their car being checked. What was interesting to the government though was how such a heavily populated region like the Bay Area had a fairly low rate on air pollution.
The terms smog check, smog test, and emission check all refer to the same thing. There are two different ways a smog check is implemented: ASM & TSI. TSI (Two Speed Idle) test is used to inspect all wheel drive (AWD) vehicles. The vehicle is inspected at 2500rpm and idle. This is how all vehicles were inspected prior to 1997. ASM (Acceleration Simulation Mode) test procedures involve operating the vehicle on a dynamometer at 15 mph and 25 mph under load. Operating an ASM test allows for the measurement of a third pollutant nitrogen oxide (NOx).
A portion of the smog check fee funds air pollution programs. Six dollars from the fee goes to the Air Pollution Control Fund which funds air pollution reduction programs such as the Carl Moyer Program.
According to the California DMV website, these counties require smog checks countywide.
San Luis Obispo
These counties require smog check only in certain zip codes.
These counties do not require smog check.
Nitrogen oxide can refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds:
In atmospheric chemistry, air pollution, and related fields, nitrogen oxides refers specifically to xNO (NO and NO2).
Only the first three of these compounds can be isolated at room temperature. N2O3, N2O4, and N2O5 all decompose rapidly at room temperature. NO3, N4O, and N(NO2)3 are very reactive.
N2O is stable and rather unreactive at room temperature, while NO and NO2 are quite reactive but nevertheless quite stable when isolated.
NOx (often written NOx) refers to NO and 2NO. They are produced during combustion, especially at high temperature. These two chemicals are important trace species in Earth's atmosphere. In the troposphere, during daylight, NO reacts with partly oxidised organic species (or the peroxy radical) to form NO2, which is then photolysed by sunlight to reform NO:
The oxygen atom formed in the second reaction then goes on to form ozone; this series of reactions is the main source of tropospheric ozone. CH3O2 is just one example of many partly oxidised organic molecules that can react with NO to form NO2.
These reactions are rather fast so NO and NO2 cycle, but the sum of their concentration ([NO] + [NO2]) tends to remain fairly constant. Because of this cycling, it is convenient to think of the two chemicals as a group; hence the term NOx.
In addition to acting as a main precursor for tropospheric ozone, NOx is also harmful to human health in its own right.
NOx may react with water to make nitric acid, which may end up in the soil, where it makes nitrate, which is of use to growing plants.
Oxidized (cationic) and reduced (anionic) derivatives of many of these oxides exist: nitrite (), nitrate (), nitronium (), and nitrosonium (). NO2 is intermediate between nitrite and nitronium:
The California Smog Check Program requires vehicles that were manufactured in 1976 or later to participate in the biennial (every two years) smog check program. The program’s aim is to reduce air pollution from vehicles by ensuring that cars with excessive emissions are repaired. With some exceptions, gas-powered vehicles that are six years old or newer are not required to participate; instead, these vehicles pay a smog abatement fee for the first 6 years in place of being required to pass a smog check. The six-year exception does not apply to nonresident (previously registered out-of-state) vehicles being registered in California for the first time, diesel vehicles 1998 model or newer and weighing 14,000 lbs or less, or specially constructed vehicles 1976 and newer. The program is a joint effort between the California Air Resources Board, the California Bureau of Automotive Repair, and the California Department of Motor Vehicles.
A Smog Check is not required for electric, hybrid, diesel powered manufactured before 1998 or weighing over 14,000 lbs, trailers, motorcycles, or gasoline powered vehicles 1975 or older.
Although vehicles 1975 and older are not required to get a smog check, owners of these vehicles must still ensure that their emissions systems are intact.][
Anyone wishing to sell a vehicle that is over four years old must first have a smog check performed. It is the seller’s responsibility to get the smog certificate prior to the sale. If the vehicle is registered in California and was acquired from a spouse, domestic partner, sibling, child, parent, grandparent, or grandchild it is exempt.
According to the California EPA, "Californians set the pace nationwide in their love affair with cars". The state’s 34 million residents own approximately 25 million cars—one for every adult aged 18 years or older.
Smog is created when nitrogen oxides (NOx) and hydrocarbon gases (HC) are exposed to sunlight. The five gasses monitored during a smog check are Hydrocarbons (HC), Carbon Monoxide (CO), Nitrogen Oxides (NOx), Carbon Dioxide (CO2), and Oxygen (O2).
On a cumulative basis, California has the worst air quality in the nation. Ozone and particulate matter are of greatest concern.][ The current control programs for motor vehicles cost $10 billion per year.
In 1998 the Air Resource Board identified diesel particulate matter as carcinogenic. Further research revealed that it can cause life-shortening health problems such as respiratory illness, heart problems, asthma, and cancer. Diesel particulate matter is the most common airborne toxin that Californians breathe.
Between 2005 and 2007 air pollution led to almost 30,000 hospital and emergency room visits in California for asthma, pneumonia, and other respiratory and cardiovascular ailments. A study by RAND Corporation showed the cost to the state, federal and private health insurers was over $193 million in hospital-based medical care. John Romley lead author of the study. said "California's failure to meet air pollution standards causes a large amount of expensive hospital care." According to the American Lung Association, California’s dirty air causes 19,000 premature deaths, 9,400 hospitalizations and more than 300,000 respiratory illnesses including asthma and acute bronchitis.
A study of children living in Southern California found that smog can cause asthma. The study of over 3,000 children showed those living in high-smog areas were more likely to develop asthma if they were avid athletes, when compared to children who did not participate in sports.
More people in California live in areas that do not meet federal clean air standards than in any other state. A report by the American Lung Association states that some areas in California are the most polluted in the United States, with air quality that is likely damaging the health of millions of people. The report finds that Los Angeles, Bakersfield (CA), and Visalia-Porterville (CA) rank among the five U.S. cities most polluted with particulates and ozone.
Carbon dioxide (CO2) is a greenhouse gas that is associated with global warming. Vehicles are a significant source of CO2 emissions and thus contribute to global warming. According to an advocacy group Environmental Defense, in 2004, automobiles from the three largest automakers in the US – Ford, GM, and DaimlerChrysler – contributed CO2 emissions that were comparable to those from the top 11 electric companies.
Historically, California was hottest in July and August, but as climate change takes place, the temperature may be extended from July through September, according to a report from the team established by the Air Resource Board. Some climate change simulations indicate the global warming impact on California will be an increase in the frequency of hot daytime and nighttime temperatures. The climate change simulations also indicate that drying in the Sacramento area may be evident by the mid 21st century. The California sea level has risen at about 7 inches per century, but this trend could change with global warming. According to the report by the Climate Action Team, “[t]he sea-level rise projections in the 2008 Impacts Assessment indicate that the rate and total sea-level rise in future decades may increase substantially above the recent historical rates”. While all sectors are vulnerable to rising sea-levels, 70 percent of those at risk are residential areas. Hospitals, schools, water treatment plants, and other buildings may be at risk of flooding.
Climate change may also affect California’s diverse agricultural sector, since it is likely to change precipitation, temperature averages, pest and weed ranges, and the length of the growing season (this affecting crop productivity). In one study, researchers looked at the possible effects on the agricultural sector in the US and identified some possible effects. Results suggested that climate change will decrease annual crop yields in the long-term, especially for cotton.
Climate change in California could also impact energy consumption. Demand patterns for electricity might be affected as the mean temperatures and the frequency of hot days increases, increasing demand for cooling in summertime.
Air pollution has two primary sources,][ biogenic and anthropogenic. Biogenic sources are natural sources, such as volcanoes that spew particulate matter, lightning strikes that cause forest fires, and trees and other vegetation that release pollen and spores into the atmosphere.
Californian greenhouse gas emissions come mostly from transpiration, utilities, and industries including refineries, cement, manufacturing, forestry, and agriculture. In 2004, transportation accounted for approximately 40 percent of total greenhouse gas emissions in California. About 80 percent of that came from road transportation.
Population growth increases air pollution, as more vehicles are on the road. California’s large population significantly contributes to the high amount of smog and air pollution in the state.][ In 1930, California’s population was less than six million people and the total registered vehicles were two million.
California has a unique topography][ which contributes to some of the problems; the warm, sunny climate is ideal for trapping and forming air pollutants. On hot, sunny days, pollutants from vehicles, industry, and many products may chemically react with each other. In the winter, temperature inversions can trap tiny particles of smoke and exhaust from vehicles and anything else that burns fuel. This keeps pollution closer to the ground.
The first “Smog Check” program was implemented in March 1984. It came about as a result of "SB 33" which was passed in 1982. The program included a biennial and change of ownership testing, "BAR 84" idle emissions test plus a visual and functional inspection of various emission control components, a $50 repair cost limit, licensing shops to perform smog checks and mechanic certification for emissions repair competence. The program is generally known as “BAR 84” program.
In 1997 important laws were passed that made significant changes to Smog Check II.
In 1999, “AB 1105” made additional changes to the program. It authorized but did not require the Bureau of Automotive Repairs (BAR) to exempt vehicles up to six years old from the biennial smog check and gave the agency authorization to except additional vehicles by low-emitter profiling (Schwartz). It also created additional changes to the repair assistance program and provided BAR with increased flexibility for how much to pay drivers whose vehicle failed the smog check so that the vehicle may be scrapped.
In 2010 the Air Resource Board and the Bureau of Automotive Repair jointly sponsored legislation, "AB 2289", that is designed to improve the program to reduce air pollution through “the use of new technologies that provide considerable time and cost savings to consumers while at the same time improving consumer protections by adopting more stringent fine structures to respond to stations and technicians that perform improper and incomplete inspections”. The bill, which passed and will take effect in 2013, will allow for a major upgrade in technologies used to test vehicle emissions. According to ARB Chairman, Mary D. Nichols, “[t]his new and improved program will have the same result as taking 800,000 old cars off the road, also resulting in a more cost effective program for California motorists”. One way the program would reduce costs is by taking advantage of on-board diagnostic technology that has been installed on new vehicles since 1996. The program will eliminate tailpipe testing and instead use the vehicle’s own emissions monitoring systems. This system has saved consumers in 22 states time and money.
The Department of Motor Vehicles (DMV) sends a registration renewal notice which indicates if a smog check is required. If the DMV requires a smog check for a vehicle, the owner must comply with the notice within 90 days and provide a completed smog check certificate. Until a smog certificate can be provided registration will not be renewed. If the vehicle fails the smog check, the owner will be required to complete all necessary repairs and pass a smog check retest in order to complete the registration. If the costs of repairing the vehicle outweigh its value, the state may buy it and have it scrapped. The buyback program is part of California’s Consumer Assistance Program (CAP) that also offers consumer assistance for repairs related to smog check. The program is administered by the Bureau of Automotive Repair.
Air is susceptible to the Tragedy of the Commons, but that can be overcome with policy tools. In their book Environmental Law and Policy, Salzman and Thompson describe these policy tools as the "5 P’s" - Prescriptive Regulation, Property Rights, Penalties, Payments, and Persuasion.
Throughout the years there have been some tensions between the US EPA and the California EPA with disagreements centered on California’s Smog Check Policy (The Press-Enterprise, 1997). One disagreement has been over where smog checks are performed. The EPA believes that smog checks and smog tests must be done separately, to avoid conflicts of interest.
For years, California has been asking the US EPA to approve a waiver allowing it to enforce its own greenhouse gas emission standards for new motor vehicles. A request was made in December 2005, but denied in March 2008 under the Bush administration, when interpretations of the Clean Air Act found California did not have the need for special emission standards. However, shortly after taking office, president Obama asked the EPA to assess if it was appropriate to deny the waiver and subsequently allowed the waiver. US EPA’s interpretation of the Clean Air Act allows California to have its own vehicle emissions program and set greenhouse gas standards due to the state’s unique need.
Car manufacturers have been strongly opposed to the emission standards set by California, arguing that regulation imposes further costs on consumers. In 2004, California approved the world’s most stringent standards to reduce auto emissions, and the auto industry threatened to challenge the regulations in court. The new regulations required car makers to cut exhaust from cars and light trucks by 25% and from larger trucks and SUVs by 18%, standards that must be met by 2016. The auto industry argued that California’s Air Resource Board did not have the authority to adopt such regulation and that the new standards could not be met with the current technology. They further argued that it would raise vehicle costs by as much as $3,000. The agency, however, countered that argument by saying that the additional costs would only be about $1,000 by 2016.
The Obama administration has proposed setting a national standard for greenhouse gas emissions from vehicles, which could potentially increase fuel efficiency by an average of 5% per year from 2012 to 2016.
According to the California Air Resources Board, the California Smog Check program removes about 400 tons of smog-forming pollutants from California’s air every day.
On March 12, 2009, the Bureau of Automotive Repair and the Air Resource Board hired Sierra Research, Inc. to analyze the data collected in the BAR’s Roadside Inspection Program to evaluate the effectiveness of the Smog Check Program from data collected in 2003-2006. Under the Roadside Inspection Program vehicles are randomly inspected at checkpoints set up by the California Highway Patrol (CHP). One objective of the evaluation was to compare the post smog check performance of pre-1996 (1974–1995) vehicles to the post smog check performance determined from a previous evaluation collected in 2000-2002. The report made several recommendations to reduce the number of vehicles failing the Roadside test. One was to develop a method for evaluating station performance. The other was to perform inspections immediately following certifications at smog check stations. Finally, the report recommended continued use of the Roadside test to evaluate the effectiveness of the Smog Check program.
A factory (previously manufactory) or manufacturing plant is an industrial site, usually consisting of buildings and machinery, or more commonly a complex having several buildings, where workers manufacture goods or operate machines processing one product into another.
Factories arose with the introduction of machinery during the Industrial Revolution when the capital and space requirements became too great for cottage industry or workshops. Early factories that contained small amounts of machinery, such as one or two spinning mules, and fewer than a dozen workers have been called "glorified workshops.
In journalism, a human interest story is a feature story that discusses a person or people in an emotional way. It presents people and their problems, concerns, or achievements in a way that brings about interest, sympathy or motivation in the reader or viewer.
Human interest stories may be "the story behind the story" about an event, organization, or otherwise faceless historical happening, such as about the life of an individual soldier during wartime, an interview with a survivor of a natural disaster, a random act of kindness or profile of someone known for a career achievement. Smog
Health Medical Pharma