GENERAL INFORMATION.
Ozone - O3, an allotropic form of oxygen, is a powerful oxidizer of chemicals and other pollutants that are destroyed on contact. Unlike the oxygen molecule, the ozone molecule consists of three atoms and has longer bonds between the oxygen atoms. In its own way reactivity ozone ranks second, second only to fluorine.
History of discovery
In 1785, the Dutch physicist Van Ma-rum, conducting experiments with electricity, drew attention to the smell during the formation of sparks in an electric machine and to the oxidizing properties of air after electric sparks were passed through it.
In 1840, the German scientist Sheinbein, while hydrolyzing water, tried to split it into oxygen and hydrogen using an electric arc. And then he discovered that a new gas, hitherto unknown to science, had formed with a specific odor. The name “ozone” was assigned to the gas by Sheinbein because of its characteristic odor and comes from Greek word“ozien”, which means “to smell”.
On September 22, 1896, inventor N. Tesla patented the first ozone generator.Physical properties ozone.
Ozone can exist in all three states of aggregation. Under normal conditions, ozone is a bluish gas. The boiling point of ozone is 1120C, and the melting point is 1920C.
Due to its chemical activity, ozone has a very low maximum permissible concentration in the air (comparable to the maximum permissible concentration of chemical warfare agents) 5·10-8% or 0.1 mg/m3, which is 10 times the olfactory threshold for humans.Chemical properties ozone.
First of all, two main properties of ozone should be noted:
Ozone, unlike atomic oxygen, is a relatively stable compound. It decomposes spontaneously at high concentrations, and the higher the concentration, the faster the rate of decomposition reaction. At ozone concentrations of 12-15%, ozone can decompose explosively. It should also be noted that the process of ozone decomposition accelerates with increasing temperature, and the decomposition reaction itself 2O3>3O2 + 68 kcal is exothermic and is accompanied by the release of a large amount of heat.
O3 -> O + O 2
O3 + O -> 2 O2
O2 + E- -> O2-Ozone is one of the strongest natural oxidizing agents. The oxidation potential of ozone is 2.07 V (for comparison, fluorine has 2.4 V, and chlorine has 1.7 V).
Ozone oxidizes all metals except gold and the platinum group, oxidizes sulfur and nitrogen oxides, and oxidizes ammonia to form ammonium nitrite.
Ozone reacts actively with aromatic compounds with the destruction of the aromatic core. In particular, ozone reacts with phenol to destroy the nucleus. Ozone actively interacts with saturated hydrocarbons with the destruction of double carbon bonds.
The interaction of ozone with organic compounds is widely used in the chemical industry and related industries. The reactions of ozone with aromatic compounds formed the basis of deodorization technologies for various environments, premises and wastewater.Biological properties ozone.
Despite a large number of research, the mechanism has not been sufficiently revealed. It is known that at high concentrations of ozone, damage to the respiratory tract, lungs and mucous membranes is observed. Long-term exposure to ozone leads to the development of chronic diseases of the lungs and upper respiratory tract.
Exposure to small doses of ozone has a preventive and therapeutic effect and is beginning to be actively used in medicine - primarily for dermatology and cosmetology.
In addition to its great ability to destroy bacteria, ozone is highly effective in destroying spores, cysts (dense membranes that form around unicellular organisms, for example, flagellates and rhizomes, during their reproduction, as well as in unfavorable conditions for them) and many other pathogenic microbes.Technological applications of ozone
Over the past 20 years, the applications of ozone have expanded significantly and new developments are underway around the world. Such rapid development of technologies using ozone is facilitated by its environmental cleanliness. Unlike other oxidizing agents, ozone decomposes during reactions into molecular and atomic oxygen and saturated oxides. All these products are generally non-polluting environment and do not lead to the formation of carcinogenic substances as, for example, during oxidation with chlorine or fluorine.Water:
In 1857, with the help of the “perfect magnetic induction tube” created by Werner von Siemens, the first technical ozone installation was built. In 1901, Siemens built the first hydroelectric power station with an ozone generator in Wiesband.
Historically, the use of ozone began with preparation plants drinking water, when in 1898 the first pilot plant was tested in the city of Saint Maur (France). Already in 1907, the first water ozonation plant was built in the city of Bon Voyage (France) for the needs of the city of Nice. In 1911, an ozonation station for drinking water was put into operation in St. Petersburg.
Currently, 95% of drinking water in Europe is treated with ozone. In the USA, the process of converting from chlorination to ozonation is underway. There are several large stations in Russia (in Moscow, Nizhny Novgorod and other cities).Air:
The use of ozone in water purification systems has been proven in highest degree effective, but equally effective and proven safe air purification systems have not yet been created. Ozonation is considered a non-chemical cleaning method and is therefore popular among the population. However, the chronic effects of micro-concentrations of ozone on the human body have not been sufficiently studied.
With a very low concentration of ozone, the air in the room feels pleasant and fresh, and unpleasant odors are much less noticeable. Contrary to the popular belief about the beneficial effects of this gas, which is attributed in some brochures to ozone-rich forest air, in reality ozone, even when highly diluted, is a very toxic and dangerous irritant gas. Even small concentrations of ozone can have an irritating effect on mucous membranes and cause disorders of the central nervous system, which leads to bronchitis and headaches.Medical uses of ozone
In 1873, Focke observed the destruction of microorganisms under the influence of ozone, and this unique property of ozone attracted the attention of doctors.
The history of the use of ozone for medical purposes dates back to 1885, when Charlie Kenworth first published his report in the Florida Medical Association, USA. Brief information about the use of ozone in medicine were discovered before this date.
In 1911, M. Eberhart used ozone in the treatment of tuberculosis, anemia, pneumonia, diabetes and other diseases. A. Wolf (1916) during the First World War used an oxygen-ozone mixture in the wounded for complex fractures, phlegmon, abscesses, and purulent wounds. N. Kleinmann (1921) used ozone for the general treatment of “body cavities”. In the 30s 20th century E.A. Fish, a dentist, begins ozone treatment in practice.
In the application for the invention of the first laboratory device, Fish proposed the term "CYTOZON", which is still listed on ozone generators used in dental practice today. Joachim Hänzler (1908-1981) created the first medical ozone generator, which allowed precise dosing of the ozone-oxygen mixture, and thus made it possible to widely use ozone therapy.
R. Auborg (1936) revealed the effect of scarring of colon ulcers under the influence of ozone and drew attention to the nature of its general effect on the body. Work on studying the therapeutic effects of ozone during the Second World War actively continued in Germany; the Germans successfully used ozone for local treatment of wounds and burns. However, after the war, research was interrupted for almost two decades, due to the advent of antibiotics and the lack of reliable, compact ozone generators and ozone-resistant materials. Extensive and systematic research in the field of ozone therapy began in the mid-70s, when in everyday life medical practice appeared resistant to ozone polymer materials and easy-to-use ozonation units.
Research in vitro , that is, under ideal laboratory conditions, they showed that when interacting with the cells of the body, ozone oxidizes fats and forms peroxides - substances that are harmful to all known viruses, bacteria and fungi. In terms of its action, ozone can be compared to antibiotics, with the difference that it does not damage the liver and kidneys and has no side effects. But unfortunately, in vivo - in real conditions everything is much more complicated.
Ozone therapy was very popular at one time - many considered ozone almost a panacea for all ailments. But a detailed study of the effects of ozone showed that along with the sick, ozone also affects healthy cells of the skin and lungs. As a result, unexpected and unpredictable mutations begin in living cells. Ozone therapy never took root in Europe, and in the USA and Canada the official medical use of ozone is not legalized, with the exception of alternative medicine.
In Russia, unfortunately, official medicine has not abandoned such a dangerous and insufficiently proven method of therapy. Currently, air ozonizers and ozonizer units are widely used. Small ozone generators are used in the presence of people.OPERATING PRINCIPLE.
Ozone is formed from oxygen. There are several ways to produce ozone, the most common of which are: electrolytic, photochemical and electrosynthesis in gas discharge plasma. In order to avoid unwanted oxides, it is preferable to obtain ozone from pure medical oxygen using electrosynthesis. The concentration of the resulting ozone-oxygen mixture in such devices is easy to vary - either by setting a certain power of the electrical discharge, or by regulating the flow of incoming oxygen (the faster the oxygen passes through the ozonizer, the less ozone is formed).Electrolytic The ozone synthesis method is carried out in special electrolytic cells. Solutions of various acids and their salts (H2SO4, HClO4, NaClO4, KClO4) are used as electrolytes. The formation of ozone occurs due to the decomposition of water and the formation of atomic oxygen, which, when added to an oxygen molecule, forms ozone and a hydrogen molecule. This method produces concentrated ozone, but it is very energy intensive and is therefore not widely used.
Photochemical The method of producing ozone is the most common method in nature. Ozone is formed when an oxygen molecule dissociates under the influence of short-wave UV radiation. This method does not produce high concentration ozone. Devices based on this method have become widespread for laboratory purposes, in medicine and the food industry.
Electrosynthesis ozone is most widespread. This method combines the ability to obtain high concentrations of ozone with high productivity and relatively low energy costs.
As a result of numerous studies on the use of various types of gas discharge for ozone electrosynthesis, devices using three forms of discharge have become widespread:
- Barrier discharge - the most widespread, is a large set of pulsed microdischarges in a gas gap 1-3 mm long between two electrodes separated by one or two dielectric barriers when the electrodes are powered with alternating high voltage with a frequency of 50 Hz to several kilohertz. The productivity of one installation can range from grams to 150 kg of ozone per hour.
- Surface discharge - close in shape to a barrier discharge, which has become widespread in the last decade due to its simplicity and reliability. It is also a set of microdischarges developing along the surface of a solid dielectric when the electrodes are powered with alternating voltage with a frequency of 50 Hz to 15-40 kHz.
- Pulse discharge - usually streamer corona discharge, which occurs in the gap between two electrodes when the electrodes are powered with a pulse voltage lasting from hundreds of nanoseconds to a few microseconds.
- Effective in cleaning indoor air.
- Do not produce harmful by-products.
- Facilitates conditions for allergy sufferers, asthmatics, etc.
In 1997, ozonizer manufacturing companies Living Air Corporation, Alpine Industries Inc. (now “Ecoguest”), Quantum Electronics Corp. and others who violated the US FTC order were administratively punished by the courts, including a ban on further activities of some of them in the United States. At the same time, private entrepreneurs who sold ozone generators with recommendations for using them in rooms with people received prison sentences ranging from 1 to 6 years.
Currently, some of these Western companies are successfully developing active work for the sale of its products in Russia.Disadvantages of ozonizers:
Any sterilization system using ozone requires careful safety monitoring, testing of ozone concentration constants with gas analyzers, and emergency management of excessive ozone concentrations.
The ozonizer is not designed to work in:
- environment saturated with electrically conductive dust and water vapor,
- places containing active gases and vapors that destroy metal,
- places with relative humidity above 95%,
- in explosion and fire hazardous areas.
Application of ozonizers for indoor air sterilization:
- lengthens the time of the sterilization process,
- increases toxicity and oxidation of the air,
- leads to a danger of explosion,
- The return of people to a disinfected room is possible only after the ozone has completely decomposed.
SUMMARY.
Ozonation is highly effective for sterilizing surfaces and indoor air, but there is no effect of purifying the air from mechanical impurities. The impossibility of using the method in the presence of people and the need to carry out disinfection in a sealed room seriously limits the scope of its professional application.
At the beginning of May 1978, an unprecedentedly high ozone content in city air was recorded in London - 18:1,000,000, i.e. There were 18 parts of ozone per 1 million parts of air.
It would seem that there is nothing wrong with this.
Almost everyone perceives air ozonized during a thunderstorm as particularly fresh and clean. This is what it actually is, but only as long as the amount of ozone does not exceed a certain limit. In high concentrations it is toxic to living organisms.
A dose of 0.2–0.3 mg/m3 is considered harmful for humans. The maximum permissible concentration (MPC) of ozone in the air, established by the World Health Organization (WHO), is 6 parts per 1 million. Thus, on that May day, the content of this gas in the air of London exceeded the MAC three times. (For comparison, we point out that the background, normal ozone content in the air of Southern England is 2–4 parts per 1 million.) It is clear that no thunderstorm, even a very powerful one, can cause the appearance of such an amount of ozone, therefore its excess amount is the result of human activity. This gas is widely used for disinfection, disinfection of drinking water, deodorization of foul-smelling substances, purification of industrial wastewater, and bleaching of fabrics. It is used in many technological processes
, for example, in the organic synthesis of various fatty acids, epoxy resins.
Enterprises of the fuel and energy complex are also to blame for the increase in ozone concentration in the atmosphere. They emit large amounts of sulfur dioxide and nitrogen oxides into the air, the molecules of which, under the influence of ultraviolet rays of the solar spectrum, are able to enter an active state with the release of atomic oxygen. The latter reacts with molecular oxygen in the air, resulting in the formation of ozone - the most important component of the so-called photochemical smog. It is unnecessary to remind about how this thick fog - an aerosol of harmful substances contained in emissions and soot, ozone and toxic metals - affects humans. In many large industrial cities
on days of smog, there is a significant increase in mortality due to exacerbation of chronic diseases of the cardiovascular system, respiratory tract, etc.
The most sensitive to ozone are grapes, citrus fruits, tobacco, spinach, radishes, beans, potatoes, tomatoes, and alfalfa. As a rule, ozone damage to grapes is accompanied by the appearance of dark brown spots on the upper side of adult leaves. Moreover, older ones are more damaged than younger ones.
In the Great Lakes region (USA), where the ozone concentration is 0.2 mg/m3, grape leaves not only lose their green color, but also fall off prematurely. In clover and ryegrass, under the influence of increased doses of this photooxidant, the leaf surface itself is significantly reduced - by 50 and 35%, respectively. Changes and appearance
leaves. At first they become silvery and glossy, then chlorotic with areas of necrosis. Their tips become discolored and white.
A study of damaged grape and petunia leaves revealed a general pattern: ozone has a predominant effect on the leaf pulp (the so-called columnar parenchyma). The first symptom of intracellular damage is the destruction of chloroplasts and the accumulation of breakdown products in the form of a general homogeneous, unstructured mass.
Changes in the structure of chloroplasts affect the intensity of photosynthesis. The rate of assimilation of carbon dioxide is especially noticeably reduced under the influence of ozone in sunflower. Japanese researchers have found that ozone affects not only photosynthesis itself, but also the distribution of its products in the cell. According to most of them, the primary target of ozone action is
cell membrane
, the permeability of which changes sharply.
It has been established that not only different species, but also different varieties of the same plant species react differently to air pollution. Why were some of them more sensitive to ozone than others?
Special experiments have shown that plants of resistant varieties differ in the speed of physiological reactions to increased ozone concentrations. They close their stomata faster and therefore accumulate less toxic gas. Of course, for the purposes of biological monitoring, particularly sensitive plant varieties are needed. These include, for example, Pinto beans, which react very sensitively to excess ozone and hydroxyacetyl nitrate vapors in the air. Specially bred varieties of tobacco that differ hypersensitivity
to this oxidant. In 1967–1968 In certain regions of Germany, ozone air pollution was determined by analyzing the symptoms of damage to indicator plants - tobacco variety BeIC3.
In 1981, to more accurately account for damage to indicator plants by ozone, a method was proposed that included two stages: – photographing damaged leaves in natural conditions
(in field);
- a measurement carried out on negatives using a television camera connected to a computer.
Using a green filter when photographing leaves makes it possible to obtain negatives in which necrotic areas appear as dark spots on a white background, the sizes of which are accurately calculated using computer technology. The effect of ozone on tobacco tissue culture in an artificial nutrient medium caused its pieces to turn brown. To others
characteristic feature
The effect of ozone on plants is the inhibition (until complete cessation) of pollen germination. This phenomenon has also been proposed to be used as a biotest to increase ozone concentration. The rate of growth of pollen tubes can be used to determine the ozone content in the air. Work in this direction continues, which indicates the importance attached throughout the world to biomonitoring of the presence of ozone in the atmosphere, an extremely widespread and dangerous toxicant. More than 300 thousand people die every year due to the unfavorable state of the environment in Russia. To the traditional ones that existed in our country for many years
environmental problems
Another one has been added - the problem of tropospheric (ground-level) ozone. Ozone: good at the top, bad at the bottom, depriving us of protection from excess ultraviolet radiation from the Sun, which is destructive for all living things. Against this background global problem It would seem that the influence on our health of other ozone found in the ground air that we breathe seems completely innocent. People pay attention to air pollution from industrial emissions and car exhaust, but few people know how dangerous ground-level ozone is for the human body.
The toxicity of ozone (O3) is manifested as a result of its effect on the respiratory system of humans and animals. Ozone is highly chemically active; minimal concentrations are sufficient to exhibit its toxic effects. It is an almost ideal chemical warfare agent, and only because of its difficulty
received, it was not among the combat gases used during the First World War. Among its disadvantages, the military includes a pungent odor.
The danger of ground-level ozone, the conditions under which it occurs, and the need to develop methods of protection have long been of concern to the public and governments of industrialized countries.
There is an international term “pre-industrial ozone”. Its concentration in the air was 10-20 μg/m3. The development of motor transport has led to a significant increase in ozone concentration in the troposphere. Americans call this ground-level ozone “bad”, in contrast to good - stratospheric ozone. Industrialized countries faced this disaster several decades ago, and Russia only in the late 1990s.
How is ozone formed?
Elevated levels of ground-level ozone occur only under certain meteorological conditions - in hot weather.
In the ground layer of the atmosphere, the main source of ozone is photochemical reactions, which involve nitrogen oxides, volatile hydrocarbons (vehicle exhaust and industrial emissions) and a number of other substances. These components are called ozone precursors. Under the influence of wind, they can spread hundreds of kilometers. When the level of solar radiation is low (cloudy summer weather, autumn, winter), photochemical reactions in the surface atmosphere are absent or proceed very sluggishly. But as soon as solar radiation increases, especially in calm weather, the air in the city and beyond becomes especially toxic.
In the hot summer of 2002, in a traditional resort location in the far Moscow region, we recorded ozone levels exceeding 300 μg/m3! What do these numbers mean?
Ozone is a substance of the highest class of danger; its toxicity is superior to hydrocyanic acid and chlorine, which are chemical warfare agents. The World Health Organization has classified ozone as a non-threshold substance, i.e. any concentration in the air of this gas, a strong carcinogen, is dangerous to humans. The maximum permissible ozone concentrations in Russia are:
- for residential areas 30 μg/m3 (average per day) and 160 μg/m3 (average over 30 minutes and no more than 1% repeatability per year);
- for industrial areas - no more than 100 μg/m3.
The European Union has adopted a standard of 110 μg/m3 for 8 hours of daylight.
What are the health hazards of ozone?
Ozone enters the body with inhaled air. Ozone has a general toxic, irritant, carcinogenic, mutagenic, genotoxic effect; causes fatigue, headache, nausea, vomiting, respiratory tract irritation, cough, respiratory distress, chronic bronchitis, emphysema, asthma attacks, pulmonary edema, hemolytic anemia (from the reference book by Y.M. Glushko “Harmful inorganic compounds in industrial emissions into the atmosphere"; L.: Chemistry, 1987).
And this information was taken from the American government environmental website (www.epa.gov/air now (environmental Protection Agency). US scientists have determined that one in three Americans is hypersensitive to ozone. People in this group can seriously harm their health if they do not monitor reports on the content of ozone in the surface layers of the atmosphere in the areas where they live. Such information is provided by the EPA (Environmental Protection Agency) together with the US Government. By receiving it, people optimize their decisions.
Impact of ozone on human health:
- causes irritation of the respiratory system, cough, heaviness in the chest; these symptoms can last several hours and become chronic;
- reduces pulmonary function;
- promotes the development of asthma and increases the number of attacks;
- provokes the occurrence of allergic reactions;
- damages the tissues of the bronchi and lungs;
- contributes to the occurrence of infertility in men;
- significantly reduces immunity;
- provokes carcinogenic and mutagenic processes.
Scientists have identified four groups of people who are at increased risk of negative effects from ozone:
- children;
- adults who, due to their occupation, spend a lot of time actively moving in the open air;
- people who are highly sensitive to ozone (scientists cannot yet determine the reason);
- aged people. This group also includes patients with chronic diseases of the respiratory system and cardiovascular system.
How to protect yourself from the effects of ground-level ozone?
If you find out about its increased concentration, there is only one way out - avoid being in the open air; if this is not possible, limit your stay outside as much as possible and do not move actively; do not allow children to go outside.
Scientists at Yale University in the USA have published data on negative impact ozone on human health. They compared mortality data with ozone emissions data for 95 cities over the period 1987-2000. An increase in air ozone concentration of 20 μg/m3 leads to an increase in deaths in the next week by more than 0.5% of the total number of deaths.
In 2005, several European countries signed the Protocol on the Control of Pollutant Emissions. European experts have calculated that by reducing emissions of ozone precursors (nitrogen oxides and volatile hydrocarbons), the number of days in which intensive formation of tropospheric ozone occurs will decrease by approximately 40%.
With a decrease in harmful emissions from industry and road transport (and, accordingly, a decrease in the formation of ground-level ozone), the number of years of life, lost people due to chronic diseases, there will be 2.3 million fewer years in 2010 than in 1990. Mortality rates among children and adolescents caused by the presence of this dangerous gas and microparticles in the atmosphere could be reduced by approximately 47,500 cases. The harmful effects of increased ozone concentrations on plant growth will decrease by 44% compared to 1990.
In Russia in 1993, damage from increased ozone levels for rye and wheat alone amounted to $150 million, and in Europe - more than $2 billion.
The analysis carried out during the negotiations on the conclusion of the Protocol showed that the expected benefits from its implementation (improved public health, increased productivity in agriculture, limiting damage to buildings and monuments) significantly exceeds the cost of the projected costs (at least 3 times) to implement this document.
We conducted an experiment on simultaneous measurement of ozone with two identical gas analyzers in Moscow and in a resort area in the far Moscow region. It turned out that during the period of summer measurements, ozone concentrations in city air were lower than similar indicators in the atmosphere of the resort area. The paradoxical fact was explained using a model of the formation of this gas in the suburbs of megacities, which was developed by foreign scientists. The essence of the method is as follows.
On the leeward side of the metropolis, ozone concentrations begin to increase at a distance of approximately 20 km from the city and reach maximum values at a distance of 50-60 km from it. In the urban environment there are constantly powerful sources of nitrogen oxides. They react with ozone and neutralize it, but outside the city there are no such sources and excess ozone remains in the air.
These reactions are cyclical and determine the equilibrium in the atmosphere. Thus, outside the city, the photochemical equilibrium is established towards high ozone values, and in the urban environment - towards lower values. But this does not mean that the air in the metropolis is safer. Behind last years The atmosphere of Moscow has turned into a chemical reactor producing highly toxic compounds. In the presence of nitrogen dioxide (and there is always a lot of this gas in city air), ozone becomes 20 times more toxic. Muscovites, escaping the summer heat in their dachas, have no idea what danger they are exposing their health to. The only salvation is a cold, cloudy and rainy summer! Climate warming in the Moscow region could lead to a catastrophic situation with the level of ground-level ozone, especially if our authorities continue to consider it useful.
A few words should be said about another popular myth. In fiction you can find the phrase “after a thunderstorm, there is a wonderful smell of ozone.” Almost all people, including the Minister of Ecology, believe that the more ozone in the air, the better it is for health; you need to breathe as deeply as possible. Meanwhile, long-term measurements of ozone in resort areas and cities always show one picture: - after a thunderstorm and rainfall, ozone disappears in the surface atmosphere.
How is the problem of tropospheric ozone solved in the United States and the European Union? In Europe, there are more than 10 thousand monitoring stations for ozone precursors and ozone itself. The information received is used to alert the population. The most visited website in Germany is about the ozone content in the air. Based on the data obtained, the environmental policy of the EU member countries is formed. The United States and Europe have already managed to achieve an annual reduction in ozone concentrations in the atmospheric air.
There is not a single ozone monitoring station or its predecessors in Russia, although there are high-quality analytical equipment for monitoring ozone levels, and specialists who offer ways to solve this problem. The authorities have neither the will nor the desire to delve into it.
How do officials who formulate environmental management policies, officials who build palaces on the most expensive and most dangerous land in the Moscow region react to this most acute situation?
On August 22, 2004, Federal Law No. 12 “On Amendments to Legislative Acts” was adopted Russian Federation and the recognition as invalid of certain legislative acts of the Russian Federation in connection with the adoption of federal laws “On amendments and additions to the Federal Law “On general principles organizations of legislative (representative) and executive bodies of state power of the constituent entities of the Russian Federation" and "On the general principles of organization local government In Russian federation".
The title of the law would seem to indicate that the changes should concern state authorities and local self-government. We are convinced that this law has made significant changes in the lives of all Russian citizens, and not of a positive nature. The trend of changes in the field of environmental legislation does not inspire optimism; it demonstrates the fact of self-removal of government authorities from fulfilling obligations to society to ensure environmental safety and the elimination of legal guarantees and practical mechanisms for environmental protection. The most important negative aspect of the adopted changes is the deprivation of environmental activities from state financial support, as well as unconstitutional changes in terms of the division of powers between federal authorities and authorities of the constituent entities of the Russian Federation.
Legal protection mechanisms have been eliminated atmospheric air in cities.
The federal authorities have abdicated responsibility for the lives and health of millions of citizens.
Federal Law “On the Protection of Atmospheric Air”
Air quality is one of the determining factors in the state of the environment. The general trend in the development of legislation in this area demonstrates a departure from compliance with constitutional guarantees of the right of citizens to a favorable environment.
The state of atmospheric air in cities such as Moscow, Novokuznetsk, Cherepovets, Kemerovo, Chelyabinsk, Yekaterinburg is catastrophic. People living in cities are forced to breathe toxic emissions from industrial enterprises that exceed the maximum permissible standards by hundreds of times. The latest changes made to the Federal Law “On the Protection of Atmospheric Air” deprive them of even the theoretical opportunity to change the situation in the future.
Perhaps the fate of a significant part of the Russian population, which ensures the well-being of the country, does not concern either the executive or legislative authorities. However, it would seem that even those in power should not be indifferent to their own lives. There is an opinion that Moscow is in a special situation and the difficulties experienced in the regions are not familiar to Muscovites, and the government, the president and deputies of the State Duma generally live on another planet. In many ways, this opinion is justified, but not in the situation with air. And the homeless person, and the president, and the chairman of the government, living in Moscow, breathe the same air.
Amendments have been made to the Federal Law “On the Protection of Atmospheric Air”, indicating the complete elimination of the air protection system.
Article 8 (repealed)
"The specially authorized federal body executive power in the field of atmospheric air protection, in accordance with the established procedure, carries out activities in the field of atmospheric air protection together with other federal executive authorities within the limits of their competence and interacts with executive authorities of the constituent entities of the Russian Federation.”
Article 9 (repealed)
"1. Legal entities that have sources of emissions of harmful (pollutant) substances into the atmospheric air, as well as harmful physical effects on the atmospheric air, develop and implement measures to protect the atmospheric air in the field of atmospheric air protection.
2. Taking into account measures to reduce emissions of harmful (pollutant) substances, atmospheric air monitoring data, results of monitoring emissions of harmful (pollutant) substances, results of calculations of dispersion of emissions of harmful (pollutant) substances, the specially authorized federal executive body in the field of atmospheric air protection, its territorial bodies develop relevant federal target programs, programs of constituent entities of the Russian Federation and local programs for the protection of atmospheric air.
Measures to protect atmospheric air should not lead to pollution of other environmental objects.
3. Draft programs for the protection of atmospheric air may be submitted for discussion by citizens and public associations in order to take into account their proposals when planning and implementing measures to improve the quality of atmospheric air.
Article 10 (repealed)
“Financing of programs for the protection of atmospheric air and measures for its protection is carried out in accordance with the legislation of the Russian Federation.”
Analyzing the changes made to the legislation, the following conclusions can be drawn:
1. The specially authorized body for the protection of atmospheric air has been liquidated, and responsibility for the appalling state of the air environment in a huge number of Russian cities with developed industry has actually been removed from the federal government. The state of the air in them poses a threat not only to health, but also to people’s lives (Article 8)
2. Air protection programs have been eliminated (Article 9).
3. Legal entities that have sources of emissions of harmful substances are relieved of the obligation to protect atmospheric air.
4. The responsibility for developing and implementing programs and carrying out measures to protect atmospheric air has been removed from the federal authorities and the authorities of the constituent entities of the Russian Federation.
5. Public control and participation in the planning and implementation of air protection programs has been eliminated.
6. Funding for programs and activities to protect atmospheric air has been eliminated (Article 10).
Recognition of these articles as no longer in force makes the very existence of the Law on Atmospheric Air Protection in Russia meaningless.
The population of all industrial cities of Russia living in conditions of catastrophic air pollution is left without guarantees of legal protection.
A.M. Chuchalin, O.A. Yakovleva, V.A. Milyaev, S.N. Kotelnikov.
In cities, the air is heavily polluted by harmful emissions from vehicles and industrial enterprises, which emit a whole range of substances, each of which to varying degrees intensity negatively affects human health.
For all pollutants, there are standards for maximum permissible concentrations (maximum permissible concentrations) of substances in the air. Compliance with these standards must be monitored by special bodies (in Moscow this is the State Public Administration “Mosekomonitoring”) and in case of systematic violation, certain sanctions must be imposed: from a fine to the closure of an enterprise.
This page contains brief characteristics some of the most common harmful substances emitted into the air by vehicles and industrial enterprises.
Hazard class of harmful substances— a conditional value intended for a simplified classification of potentially hazardous substances.
Standard GOST 12.1.007-76 “Classification of harmful substances and General requirements security" establishes the following criteria for determining Hazard class of harmful substances:
Based on the degree of impact on the body, harmful substances are divided into four hazard classes:
I substances are extremely dangerous
II highly hazardous substances
III moderately hazardous substances
IV low-hazard substances
MPC- maximum permissible concentration of a pollutant in the atmospheric air - a concentration that does not have a direct or indirect adverse effect on the present or future generation throughout life, does not reduce a person’s performance, does not worsen his well-being and sanitary living conditions.
PDKss- maximum permissible average daily concentration chemical substance in the air populated areas, mg/m3. This concentration should not have any direct or indirect harmful effects on humans if inhaled indefinitely (years).
Characteristics of harmful substances.
Sulfur dioxide (sulfur dioxide) SO2
Hazard class - 3
MPCss - 0.05
MPCmr - 0.5
Colorless gas with a characteristic pungent odor. Toxic.
In mild cases of sulfur dioxide poisoning, cough, runny nose, lacrimation, dry throat, hoarseness, and chest pain appear; in case of acute poisoning of moderate severity, in addition, headache, dizziness, general weakness, pain in the epigastric region; upon examination, there are signs of a chemical burn of the mucous membranes of the respiratory tract.
Long-term exposure to sulfur dioxide can cause chronic poisoning. It manifests itself as atrophic rhinitis, dental damage, often aggravated by toxic bronchitis with attacks of suffocation. Possible damage to the liver, blood system, and development of pneumosclerosis.
Particularly high sensitivity to sulfur dioxide is observed in people with chronic respiratory disorders and asthma.
Sulfur dioxide is formed when reserve fuels are used by thermal power complex enterprises (fuel oil, coal, low-quality gas) and emissions from diesel vehicles.
Nitric oxide (nitric oxide) NO.
Hazard Class -
MPCss - 0.06
MPCmr - 0.4
A colorless gas with a faint sweetish odor, known as “laughing gas” because significant amounts of it have a stimulating effect on nervous system. Mixed with oxygen, it is used for anesthesia in light operations.
The compound has a positive biological effect. NO is the most important biological conductor capable of causing cellular level a large number of positive changes, which leads to improved blood circulation, immune and nervous systems.
Nitrogen oxide is formed when coal, oil and gas burn. It is formed during interaction nitrogen N2 and oxygen O2 in the air at high temperatures: the higher the combustion temperature of coal, oil and gas, the more nitrogen oxide is formed. Further, at normal temperatures, NO is oxidized to NO2, which is already a harmful substance.
Nitrogen dioxide (nitrogen dioxide) NO2
Hazard class - 2
MPCss - 0.04
MPCmr - 0.085
At high concentrations it is a brown gas with a suffocating odor. Acts as an acute irritant. However, at the concentrations present in the atmosphere, NO2 is more of a potential irritant and only potentially comparable to chronic lung diseases. However, there was a slight increase in bronchitis in children aged 2-3 years.
Under the influence of solar radiation and in the presence of unburned hydrocarbons, nitrogen oxides react to form photochemical smog.
Often, various nitrogen oxides that are formed during the combustion of any type of fuel are combined into one group “NOx”. However, it is nitrogen dioxide NO2 that poses the greatest danger.
Carbon monoxide CO (carbon monoxide)
Hazard class - 4
MPCss - 0.05
MPCmr - 0.15
Gas is colorless and odorless. Toxic. In acute poisoning, headache, dizziness, nausea, weakness, shortness of breath, rapid pulse. Possible loss of consciousness, convulsions, coma, circulatory and respiratory problems.
With chronic poisoning, headaches, insomnia appear, emotional instability occurs, attention and memory deteriorate. Possible organic damage to the nervous system, vascular spasms
Carbon monoxide is formed as a result of incomplete combustion of carbon in fuel.
In particular, when burning carbon or compounds based on it (for example, gasoline) in conditions of lack of oxygen. A similar formation occurs in a stove firebox when the stove damper is closed too early (until the coals completely burn out). The carbon monoxide formed in this process, due to its toxicity, causes physiological disorders (“fumes”) and even death, hence one of the names - “carbon monoxide”
The main anthropogenic source of CO is currently exhaust gases from internal combustion engines of automobiles. Carbon monoxide is formed during the combustion of hydrocarbon fuels in internal combustion engines at insufficient temperatures or poor air supply system settings.
Carbon dioxide (carbon dioxide) CO2
Colorless gas with a faint sour odor. Carbon dioxide is not toxic, but does not support respiration. High concentrations in the air cause suffocation. Causes hypoxia (lasting up to several days), headaches, dizziness, nausea (concentration 1.5 - 3%). At conc. above 61%, working capacity is lost, drowsiness appears, breathing and cardiac activity are weakened, and life is in danger. CO2 absorbs infrared rays emitted by the Earth and is one of the greenhouse gases, as a result of which it takes part in the process
global warming
Vanadium pentoxide V2O5.
Hazard class - 1
MPCss - 0.002
Poisonous. Causes irritation of the respiratory tract, pulmonary bleeding, dizziness, disruption of the heart, kidneys, etc. Carcinogen.
The compound is formed in small quantities when fuel oil is burned. Carbon disulfide (carbon disulfide)
Hazard class - 2
CS2, colorless liquid with an unpleasant odor.
MPCss - 0.005
MPCmr - 0.03 Carbon disulfide vapors are poisonous and highly flammable. Valid to the central
In case of mild poisoning - narcotic effects, dizziness. In case of moderate poisoning, agitation occurs with a possible transition to coma. With chronic intoxication, neurovascular disorders, mental disorders, sleep disorders, etc. occur.
With prolonged poisoning, encephalitis and polyneuritis can occur. Recurrences of seizures with loss of consciousness and respiratory depression may occur. When taken orally, nausea, vomiting, and abdominal pain occur. Upon contact with skin, hyperemia and chemical burns are observed.
Xylene (dimethylbenzene)
Hazard class - 3
MPCss - 0.2
MPCmr - 0.2
Forms explosive vapor-air mixtures.
Causes acute and chronic damage to the hematopoietic organs, dystrophic changes in the liver and kidneys, and upon contact with skin - dermatitis.
Benzene
Hazard class - 2
MPCss - 0.1
MPCmr - 1.5
Colorless volatile liquid with a peculiar mild odor.
Carcinogen.
In acute poisoning, headache, dizziness, nausea, vomiting, agitation followed by a depressed state, rapid pulse, and drop in blood pressure are observed. In severe cases - convulsions, loss of consciousness.
Chronic poisoning is manifested by changes in the blood (impaired bone marrow function), dizziness, general weakness, sleep disturbance, and fatigue. In women - menstrual dysfunction.
Benzpyrene, benz(a)pyrene
Vanadium pentoxide V2O5.
MPCss - 0.01
Formed during the combustion of hydrocarbon liquid, solid and gaseous fuels (to a lesser extent during the combustion of gaseous fuels). It can appear in flue gases when burning any fuel with a lack of oxygen in certain combustion zones.
Benz(a)pyrene is the most typical chemical carcinogen in the environment; it is dangerous to humans even at low concentrations, since it has bioaccumulation properties. Being chemically relatively stable, benzo(a)pyrene can migrate for a long time from one object to another. As a result, many environmental objects and processes, which themselves do not have the ability to synthesize benzo(a)pyrene, become its secondary sources. Benz(a)pyrene also has a mutagenic effect.
Toluene (methylbenzene)
Hazard class - 3
MPCss - 0.6
MPCmr - 0.06
Colorless flammable liquid.
The limits of the explosive mixture with air are 1.3 - 7%.
Toluene (methylbenzene) is a highly toxic poison that affects the body’s hematopoietic function, just like its predecessor, benzene. Impaired hematopoiesis manifests itself in cyanosis and hypoxia.
Toluene vapor can penetrate intact skin and respiratory system, cause damage to the nervous system (lethargy, disturbances in the functioning of the vestibular apparatus), including irreversible
Chlorine
Hazard class - 2
MPCss - 0.03
MPCmr - 0.1
Yellow-green gas with a pungent irritating odor. Irritates mucous membranes of the eyes and respiratory tract. Primary inflammatory processes are usually accompanied by a secondary infection. Acute poisoning develops almost immediately. When inhaling medium and low concentrations, chest tightness and pain, rapid breathing, pain in the eyes, lacrimation, increased levels of leukocytes in the blood, body temperature, etc. are noted. Bronchopneumonia, pulmonary edema, depression, and convulsions are possible. As long-term consequences, catarrh of the upper respiratory tract, bronchitis, pneumosclerosis, etc. are observed. Activation of tuberculosis is possible. With prolonged inhalation of small concentrations, similar but slowly developing forms of the disease are observed.
Chromium hexavalent
Vanadium pentoxide V2O5.
MPCss - 0.0015
MPCmr - 0.0015
Toxic. The initial forms of the disease are manifested by a feeling of dryness and pain in the nose, sore throat, difficulty breathing, cough, etc. With prolonged contact, signs of chronic poisoning develop: headache, weakness, dyspepsia, weight loss, etc. The functions of the stomach, liver and pancreas are impaired. Possible bronchitis, asthma, diffuse pneumosclerosis. When exposed to skin, dermatitis and eczema may develop.
Chromium compounds are carcinogenic.
Soot
Hazard class - 3
MPCss - 0.5
MPCmr - 0.15
Dispersed carbon product of incomplete combustion. Soot particles do not interact with air oxygen and are therefore removed only through coagulation and sedimentation, which occur very slowly. Therefore, to maintain a clean environment, very strict control over soot emissions is needed.
Carcinogen, promotes the development of skin cancer.
Ozone (O3)
Vanadium pentoxide V2O5.
MPCss - 0.03
MPCmr - 0.16
Explosive gas of blue color with a sharp characteristic odor. Kills microorganisms, so it is used for water and air purification (ozonation). However, only very small concentrations are permissible in the air because Ozone is extremely toxic (more than carbon monoxide CO).
Lead and its compounds(except tetraethyl lead)
Vanadium pentoxide V2O5.
MPCss - 0.0003
It is poisonous, affects the central nervous system, even small doses of lead cause retardation in the development of intelligence in children. Damage to the nervous system is manifested by asthenia, and in severe forms - encephalopathy, paralysis (mainly of the extensors of the hands and fingers), and polyneurism.
With chronic intoxication, damage to the liver, cardiovascular system, and disruption of endocrine functions (for example, in women - miscarriages) are possible. Suppression of immunobiological reactivity contributes to increased overall morbidity. Fatal poisoning is also possible.
Lead affects the human nervous system, which leads to decreased
intelligence, causes changes in physical activity, hearing coordination,
affects the cardiovascular system, leading to heart disease.
This has Negative influence on the health status of the population and, firstly,
It is the turn of children who are most susceptible to lead poisoning.
Carcinogen, mutagen.
Tetroethyl lead
SHOE - 0.000003
Flammable
At temperatures above 77°C, explosive vapor/air mixtures may form.
The substance is irritating to eyes, skin, and respiratory tract. The substance may have an effect on the central nervous system, leading to irritability, insomnia, and cardiac disorders. Exposure may cause confusion. Exposure to high concentrations can cause death. Medical supervision is indicated.
With long-term or repeated exposure, it may have a toxic effect on human reproductive function.
Formaldehyde HCOH
Colorless gas with a pungent odor.
Toxic, has bad influence on genetics, respiratory organs, vision and skin. Has a strong effect on the nervous system. Formaldehyde is listed as a carcinogen.
The substance may have effects on the liver and kidneys, leading to functional impairment
Formaldehyde is used in the production of plastics, and the main part of formaldehyde is used in the production of chipboard and other wood-based materials. In them, phenol-formaldehyde resin makes up 6-18% of the weight of the chips.
Phenol
Phenol is a volatile substance with a characteristic pungent odor. Its vapors are poisonous. In case of contact with the skin, phenol causes painful burns. In acute poisoning, disturbance of respiratory functions and the central nervous system. In case of chronic poisoning - dysfunction of the liver and kidneys
Selenium dioxide
Vanadium pentoxide V2O5.
MPCss - 0.05
MPCmr - 0.1
The substance is corrosive to the eyes, skin and respiratory tract.
Repeated or prolonged contact may cause skin sensitization. The substance may cause effects on the respiratory and gastrointestinal tract, central nervous system and liver, resulting in nasopharyngeal irritation, gastrointestinal distress and a persistent garlic odor and liver damage.
Hydrogen sulfide
Hazard class - 2
MPCmr - 0.008
Colorless gas with the smell of rotten eggs.
The substance is irritating to the eyes and respiratory tract. Inhalation of the gas may cause pulmonary edema. Rapid evaporation of the liquid may cause frostbite. The substance may have effects on the central nervous system. Exposure may cause loss of consciousness. Exposure may cause death. Effects may be delayed.
Bromobenzene C6H5Br.
Hazard class - 2
MPCss - 0.03
The substance is irritating to the skin. Ingestion of the liquid may cause aspiration into the lungs with the risk of chemical pneumonia. The substance may have effects on the nervous system
May have effects on the liver and kidneys, leading to functional impairment
Methyl mercaptan CH3SH
Hazard class - 2
MPCmr - 0.0001
Colorless gas with a characteristic odor.
Gas is heavier than air. and can creep along the ground; fire may occur at a distance.
The substance is irritating to the eyes, skin and respiratory tract. Inhalation of the gas may cause pulmonary edema. Rapid evaporation of liquid can cause frostbite. The substance may have effects on the central nervous system, leading to respiratory failure. High dose exposure can cause death.
Due to its strong, unpleasant odor, methyl mercaptan is used to add to harmful, odorless gases to detect leaks.
Nitrobenzene
Hazard class - 4
MPCss - 0.004
MPCmr - 0.2
The substance may have an effect on blood cells, leading to the formation of methemoglobin. Exposure may cause confusion. Effects may be delayed.
With prolonged exposure, it may have an effect on the hematopoietic organs and the liver.
Ammonia
Ammonia NH3, hydrogen nitride (smell of ammonia), almost twice as light as air
Hazard class - 2
MPCss - 0.004
MPCmr - 0.2
A colorless gas with a sharp suffocating odor and acrid taste.
Poisonous, severely irritating to mucous membranes.
In acute ammonia poisoning, the eyes and respiratory tract are affected; at high concentrations, it can cause fatal outcome. Causes severe coughing, suffocation, and with a high concentration of vapors - agitation, delirium. Upon contact with skin - burning pain, swelling, burn with blisters. In case of chronic poisoning, indigestion, catarrh of the upper respiratory tract, and hearing loss are observed.
A mixture of ammonia and air is explosive.
Ozone is the most effective means for cleaning the air from such pollutants as:
- viruses, bacteria, fungal spores.- toxic emissions from synthetic materials and decaying organics.
- unpleasant and harmful odors.
Ozone is a natural component of the earth's atmosphere, and many scientists consider its use to be a wonderful natural method of purifying our air.
In nature, ozone is formed from molecular oxygen under the influence of sunlight and lightning., as well as in the surf and waterfalls. Ozone has a characteristic odor. At low concentrations, this odor resembles the smell of air during a thunderstorm. Ozone is not stable, it quickly turns into ordinary oxygen
.
The idea of artificial creation clean atmospheric air indoors served as a reason for the development of new environmental technology that allows its purification using destructive oxidation methods, when molecules organic matter OZONE, obtained from oxygen in the air, works. Unlike other oxidizing agents, ozone decomposes during reactions into molecular and atomic oxygen and saturated oxides. All these products do not pollute the environment and do not lead to the formation of carcinogenic and toxic substances.
The trouble is that we quickly get used to bad air, and after a while we stop noticing unpleasant odors. With the rapid growth of industry and the level of urbanization, we are breathing less and less clean air and the polluted air of ours is becoming more and more familiar to us. Everyday life
. No amount of ventilation, even very expensive ventilation, can keep the air in good condition unless ozonation is used. Often it is absolutely impossible to remove unpleasant odors by ventilation, and yet they must be removed. This is where ozone comes to the rescue.
- Air purification with ozone has many benefits. This method is very reliable, very effective and inexpensive.
- Ozone effectively destroys all known viruses, bacteria, and fungi. It has a high diffusion ability and quickly spreads throughout the entire volume of the room, penetrating into corners and crevices where air practically does not move. Ozone interacts with many toxic and unpleasant-smelling chemical compounds
- leaving no dangerous by-products.
- Excess ozone is quickly converted into molecular oxygen.
Using ozone in the home:
- Air disinfection during epidemics and diseases.
- Destruction of toxic substances and odors emitted by paint, furniture, wallpaper, carpets, detergents.
- Quickly eliminates the odors of cigarette smoke, burnt food, and fire.
- Fighting odors from pets, kitchen, toilet.
- Eliminates damp smell.
- Prevention from rotting, combating mold, removing fungus in basements, cellars, vegetable stores, baths, and places where animals are kept.
- Increasing the shelf life of food and eliminating odors in the refrigerator.
- Insect control.
- Restoring the level of natural ionization of indoor air.
- Eliminate dust mites and allergens.
- Eliminating odor in shoes.
Ozonizers do not filter the air, but create an environment in the premises that cleans itself, which is a simulation natural principle restoration of the air environment.
Ozone is the only one chemical element restoring air purity. Ozone is a natural component of the earth's atmosphere, and many scientists consider its use to be a wonderful natural method of purifying our air and water.
Ozone finds wide application in all areas commercial human activity.
You can often hear that ozone is poisonous. This is true, just as it is true that any medicine is poisonous in large concentrations, but in small concentrations it heals. So is ozone, in small concentrations it is a medicine, but in large concentrations it causes poisoning. Theoretically, it is believed that death can occur when inhaling ozone for 60 minutes when its concentration in the air exceeds the maximum permissible concentration by 500 times. But in the entire history of artificial ozone production (more than 120 years), not a single case of death from ozone poisoning has been recorded, unlike other toxic substances from which millions of people die every year.
It has been proven that ozone does not have carcinogenicity and mutagenicity. It neutralizes most toxins that have such properties.
Ozone in high concentrations can burn the mucous membranes of the respiratory system. Such concentrations can be obtained at home using equipment for commercial and industrial purposes. Sometimes people buy such equipment for various purposes because... it is affordable. Such equipment can be used in apartments only in the absence of people. Household ozonizers are not capable of reaching dangerous concentrations of ozone in the air, since they are ineffective.
When used correctly, ozone is not only safe, but also beneficial.
Ozonated water is safe at any ozone content.
Ozone concentration and effects of exposure.
Data from IOA (International Ozone Association)
ppm = Parts per million - parts per million. For ozone, 1ppm is approximately equal to 2mg/m3
0.001 ppm.
The lowest ozone concentration detected by hypersensitive people. The concentration is too low to be accurately measured by the best electronic equipment.
. 0.003 ppm - 0.010 ppm.
The threshold for odor perception of ozone by the average person is fresh air. Easily detected by most normal people. These concentrations can be measured with reasonable accuracy. Ozone levels in typical residential and office spaces equipped with normally operating air purifiers with low outdoor ozone levels. High concentrations of ozone levels outdoors can affect ozone levels in indoor air.
. 0.001 to 0.125 ppm.
Typical ozone concentrations in the natural atmosphere. These concentration levels vary with altitude, time of day, atmospheric conditions and terrain.
. 0.020 to 0.040 ppm.
Average generalized concentration of oxidizing agents in some major cities in 1964. More than 95 percent of oxidizing agents are ozone.
. 0.040 ppm.
Limit for various devices for home use in the US. Measured as the steady-state ozone concentration in the test room.
. 0.050 ppm.
Maximum permissible ozone concentrations are recommended by ASHRAE in indoor air conditioners and ventilation systems.
. 0.050 ppm.
Maximum permissible concentration of ozone produced by electronic air purifiers and similar devices for residential premises in accordance with Federal law USA for Food, Drugs and Cosmetic. (Note: Keep this indicator in mind when choosing air ozonizers for your home.)
. 0.100 ppm. (1 x MPC)
Maximum permissible concentration (MAC) of ozone in industrial work areas: permissible human exposure - 8 hours a day, 6 days a week. US standards. In Russia it is two times lower.
. 0.100 ppm.
Maximum permissible ozone concentration limits for industrial and public facilities in England, Japan, France, the Netherlands and Germany.
. 0.150 to 0.500 ppm.
Typical peak ozone concentrations in large cities.
. 0.200 ppm. (2 x maximum permissible concentration)
. Long-term exposure to a person under the conditions of a professionally conducted experiment does not lead to noticeable side effects. The threshold level of ozone at which irritation is felt in the nose and throat is in the region of 0.300 mg/kg.
. 0.300 ppm.
The level of ozone at which some sensitive plant species began to show signs of exposure.
. 0.500 ppm. (5 x maximum permissible concentration)
The ozone level at which Los Angeles, California claims its No. 1 Smog Warning. May cause nausea in some people.
. 1.00 to 2.00 ppm. (10 - 20 x MPC)
Los Angeles, California states Smog Warning #2 at 1.00 ppm. ozone concentrations and smog warning No. 3 at 1,500 ppm. Volunteers exposed to this ozone concentration for 2 hours experienced symptoms that could lead to temporary disability. Symptoms subside after a few days. Symptoms include headache, chest pain, and dry airways.
. 1.40 to 5.00 ppm.
Beans exposed to 1.4 to 5.0 ppm ozone concentrations for 70 minutes showed some signs of severe injury to mature leaves.
. 5.00 to 25.00 ppm. (50 - 250 x MPC)
Experiments have shown that 3 hours of exposure to ozone at a concentration of 12 ppm is fatal to guinea pigs. Welders who were exposed to concentrations of up to 9 ppm of ozone, plus other air pollutants, suffered pulmonary edema. After 2 - 3 weeks they recovered and x-rays showed that the lungs were normal. But after 9 months, they still complained of fatigue and shortness of breath during physical activity.
. 25.00 ppm. and higher
The concentration of ozone that is hazardous to human life after exposure for 2-3 minutes is unknown, but based on animal experiments, exposure to a concentration of 50 ppm (500 times the MAC) for 60 minutes is likely to be fatal.
