Kills air pollution trees

The age of industry

Air pollution in Santiago de Chile, Winter 2003. Photo: Michael Ertel, from >> wikipedia, accessed on March 5, 2010. License: >> FDL 1.2.

Pre-industrial air pollution

The history of air pollution began when humans did this Fire tamed: The layers of soot in prehistoric caves and blackened lungs in mummified corpses from the Stone Age prove that the air in the caves of our ancestors was not always the best. (Even today, >> air pollution from open fires - which is mainly used for cooking in poor developing countries - is one of the most pressing environmental problems.) Slash and burn The destruction of the forests since the invention of agriculture contributed to possibly >> the first large-scale environmental change, but in any case a source of air pollution. When humans >> learned to process metals, these also contributed to air pollution: In samples from the Greenland ice, traces of Lead and copper emissionsprove n from pre-industrial times; the air pollution from mining has already been reported by Agricola in his De Re Metallica from 1556. The >> air quality of medieval cities often left a lot to be desired, as historical accounts from both the Arab and Christian worlds show. The pre-industrial air pollution was limited in its effects to the immediate places of origin.

A new dimension: coal combustion

Air pollution took on completely new dimensions with the >> Industrial Revolution. Coal became the main fuel; By 1870 Great Britain had approximately 100,000 coal-fired steam engines. With falling transport costs, coal could also be transported to the cities and used there for ovens and stoves as well as for industrial plants. In Victorian England, about a quarter of all deaths were due to lung disease. With the second phase of the industrial revolution from 1870 onwards, heavy industries - iron, steel, chemicals - with huge coal consumption also emerged in other European countries as well as in the USA and Japan, and in the 20th century also in Russia, Canada, Latin America and Asia. The air around the ironworks, in the cities and in industrial areas was catastrophically poor, but it seemed to be the inevitable price of the prosperity that arose. Industrialists, workers and ministers of state saw the smoking chimneys as a symbol of progress, prosperity and power.

The first episode were polluted coal cities like London. In 1880 there were 3.5 million fire pits in London, mostly winter smog (the word combines smoke, Smoke and fog, Fog; it was coined in 1905 at the Hygiene Congress in London) became a regular event. Even pedestrians are said to have fallen into the Thames because they did not see the river; Central London had hours of sunshine 20 percent less in the 1920s to 1950s than in the suburbs. In the Ruhr area, too, coal was used before industrialization. Coal had already been found near Dortmund in the 13th century, and tunnel mining began in Muttental near Witten in 1578 - initially in horizontal tunnels. Here, too, the dirty coal was actually unpopular, but in Essen the houses were already black in 1794 due to the numerous coal stoves "as if they had been blackened on purpose" (1203).

At some point, despite all belief in progress, the consequences of air pollution could no longer be overlooked. The first efforts to keep the air clean began in the United States, in St. Louis and Pittsburgh, but were discontinued during the war. In December 1952, during a cold spell, there was a week-long smog in London, which was so thick that the other side of the street could no longer be seen, locally the visibility was even only 30 centimeters at times. A performance of the opera "La Traviata" had to be canceled because the audience could no longer see the stage - inside the theater! About 4,000 more people than usual died in London that week and the death rate remained high for three months - all in all, "the Greatsmog"(as he was later named) probably killed 12,000 people (1205). Although the government, as then Local (and later Prime) Minister Harold Macmillan said, new laws were not necessary (1206), more public care was taken Pressure that 1956 in a "Clean Air Act"(Clean Air Act) strictly regulates domestic coal-firing. It was also helpful that since 1950 >> oil and gas have increasingly replaced coal, the combustion of which produces fewer pollutants, especially smoke and soot. By 1970, the smoke content of Londoners fell Air by 80 percent, by 2005 by 98 percent.

Industrial air pollution

England, Western Europe, America

Air pollution also came from metal smelting and the chemical industry. Large-scale chemical industry emerged with the production of sodium carbonate for glass and soap production as well as the textile industry. This produced corrosive hydrogen chloride, which was released into the environment. The Alkali Inspectorate established against this pollution in 1865 on the basis of the British Alkali Act passed in 1863 is considered to be first “environmental agency” in history. (It had little effect; the situation only got better when the Solvay process used today was introduced.) With the >> second phase of the industrial revolution, the demand for copper increased. Copper mines such as the mine on the Río Tinto in Andalusia, taken over by a British consortium in 1873 and used since Phoenician times, also supplied sulfuric acid for the chemical industry; In the case of outdoor smelting (which is forbidden in England), however, part of the sulfur was released from the ore as >> sulfur dioxide, which reacts with the water in the air to form "acid rain". A British trade agent reported that "your eyes and throats ache, and all iron corrodes". In 1888 the miners went on strike against the mine operators, supported by local farmers. At a protest rally, the police shot 45 people (1215). The exhaust gases from nickel production, which became important in the 20th century (nickel is used to refine steel), also damaged the surroundings of the ironworks in a wide area. In the nickel-copper smelting works in Sudbury, Canada, for example, the ore was also smelted in the open air; When the first chimney was built in 1920, the area had already been turned into a black desert (1215).

Worst of all, however, was the air pollution in industrial areas that had both coal and ore deposits at their disposal, such as in the Ruhr area, in the “Black Country” in Central England or in the Great Lakes region in North America. One of the first environmental crises was the October smog in the small town Donora (Pennsylvania, USA), where in October 1948 an inversion weather prevented the clouds of smoke from the local steel and zinc works; around half of the 14,000 inhabitants suffered from respiratory or cardiovascular diseases, 40 people died. The steel company "American Steel" blamed the inversion weather situation for the damage and denied any complicity; after this and similar events, however, scientific research into the connections between air pollution and damage to health began.

Example of the Ruhr area

In Europe that became Ruhr area to symbolize environmental pollution. In the coal-rich region, the first ironworks went into operation in 1756; the actual industrialization did not begin until the middle of the 19th century. In 1834 the marl layer was first cut at the Franz colliery near Essen-Borbeck, which covered the coking coal further north in the Ruhr area, and with the introduction of the coke oven, the steam engine and the opening up of the Ruhr area by railways, the actual industrialization began around 1850 (1219) . There were complaints about this mainly from neighbors, such as farmers, whose harvests were spoiled by the toxic exhaust gases from metal works or chemical plants. Most of the residents were "proud of the American-called development of their hometown and its neighborhood" and felt "as members of a determined community full of hard work and creativity" (1220). In the Ruhr area, too, enormous amounts of sulphurous acid were released during the smelting of ores, and the Ruhr coal also contained between 0.5 and 3 percent sulfur, which was also released during combustion - in the Ruhr area, particularly sulphurous coal was even preferred because it was cheaper and was less suitable for export. The zinc smelter built near Essen-Borbeck in 1847 burned 105 tons of coal a day in 1884 and released 3,700 kg of sulphurous acid.

In 1900 the Ruhr area was already the largest industrial region in Europe, and probably also the most polluted (1215). In Essen, officials reported in 1912 that near the Krupp factory and the colliery, dusting twice a day in the apartments was the least that had to be done, and that the dust consisted almost entirely of coal and soot particles "sometimes of considerable size". Since the steel and iron works of Krupp and Thyssen were of central importance for the German armaments industry, serious environmental regulations hardly stood a chance, although there were already legal possibilities to do so (1230). For the industrial unions, too, jobs mattered more than the environment. So it came to the complaint everywhere Soot and smoke plagueThe construction of taller chimneys (1232) hardly changed, as the steadily increasing number of factories negated their effect (the toxic substances contained in the smoke from the iron and steel industry such as lead, cadmium, arsenic and fluoride were only gradually perceived as a problem Medicine of the time suspected connections between air pollution and illnesses, but could hardly prove this due to a lack of knowledge of the mechanisms of spread and action [1233]). The extent of air pollution in the Ruhr area became clear when in 1923, after the occupation by French troops (because reparations payments were suspended after the First World War), strikes paralyzed coal, coke and steel production: the sky became visible again; the harvests increased by half, the annual rings on the trees were thicker than in the years before and after. The working-class families suffered from hunger and misery during this period, and so air pollution continued to be accepted as a necessary evil (1235). The visible situation in the cities became better with the electric current: countless steam engines could be replaced by power plants built outside the cities. These too polluted their surroundings considerably, the power plant built at the beginning of the 1920s at Harkortsee, which is located when the weather was blowing, emitted so much ash that the lake was completely covered by a layer of ash in foggy weather (the responsible district committee "im Life interest "apart from the work), but the pollution hit fewer people.

When in 1927 the most modern coal mine power plant without flue gas dedusting went into operation in Sodingen near Herne, the neighboring school had to be closed due to the enormous fly ash emissions - it was never reopened, but after two of the three boilers of the power plant were shut down due to the economic crisis , 1930 temporarily housed homeless people (1220). During the global economic crisis, research into the question of whether industrial air harms people and the environment was also stopped due to a lack of funds. The attitude towards air pollution did not change under the Nazis either, the armaments boom and the preparations for war even worsened the situation (“The Nazis' passion was probably for German blood and German soil, but not for German air.” [John R. McNeill , 1215]). The power plant at Harkortsee, about which other industrial companies have now also complained and which severely impaired tourism, was not allowed to build a taller chimney, as this would make the plant "too conspicuous for air exploration". The electrostatic precipitators decided upon could not be installed there the application for an allocation for iron in favor of the defense industry was rejected. After all, smoke and haze over the Ruhr area during the Second World War meant that the Allied bombs were less targeted here than elsewhere. Most of the industrial plants were nevertheless destroyed - and air pollution fell again.

But in the Cold War Europe needed German coal, German iron, and German steel; the Ruhr area was quickly rebuilt as an industrial area. With the economic miracle, iron and steel production reached new records and the chemical industry was expanded. In the 1950s, well over 300,000 tons of dust per year passed over the Ruhr area, measurements in the (particularly polluted) northern districts of Duisburg showed dust loads of up to 6.8 kg per 100 square meters per month. Applications for the city to finance model trials against particularly air-polluting companies were rejected by the City Director, but 51 measuring points were set up for systematic air testing: and peak values ​​of 20.2 kg of dust per 100 square meters per month were measured. The displeasure about almost unbearable clouds of smoke, against which there were practically no possibilities of action, led to the establishment of the "Interparliamentary Working Group for Natural Economy" (IPA), founded in 1952, which also advocated a law on air pollution control from the mid-1950s. At the Association of German Engineers (VDI), a commission for keeping the air clean was set up to develop proposals for this. But the population was more interested in the "economic miracle" than in clean air; The Basic Law also did not contribute to the further development of environmental protection, since the federal government had hardly any legislative powers here (1240). At least the work contributed to the fact that the possibility of neighbors and injured parties to claim damages was improved: In 1959 the obligation contained in the German Civil Code (BGB) to tolerate "local" burdens without compensation was dropped (1241). But that did not prevent air pollution from occurring. With the change in the trade regulations taking place at the same time, however, the possibility of a subsequent order was created which, at least in theory, gave the authorities a tool for improving air quality.But when the coal from the Ruhr area is no longer competitive with the cheaper (because not mined so deeply underground) coal from abroad (and also with the cheaper oil) at the end of the 1950s, its mining is promoted with subsidies, the old one Thinking in terms of trade taxes and jobs is gaining ground.

The turnaround, which began to be quietly heralded, intensified in the 1960s. A decline in economic growth made the limits of the "economic miracle" visible for the first time, and voices of skepticism were increasingly heard. In 1961, Chancellor candidate Willy Brandt picked up on this mood at a party congress and talked about the fact that the sky over the Ruhr area had to turn blue again. Brandt wanted to make the SPD eligible for election beyond the workforce, but the slogan was hardly taken seriously (a politician who promised the blue of the sky ...); and Brandt was not elected either. But in 1962 North Rhine-Westphalia (without a vote against) created the first state pollution control law, a "modern" law on air pollution control, which became the model for the later federal pollution control law. In the administrative authorities, however, this law and later environmental laws were not implemented (1245), and so the practical environmental protection often continued to consist in the construction of tall (and even higher) chimneys so that the polluted air could be further dispersed by the wind.


Japanese industrialization from the >> Meiji period also produced heavily polluted industrial areas, such as the Hanshin region (Osaka-Kobe). From 1880 iron and steel works, cement and chemical works were built here; by 1900 the population of Kobe and Osaka quadrupled. From 1912 onwards, air pollution was measured: it was as bad as in London. Production and air pollution continued to rise (planes even reportedly crashed due to poor visibility) until the American Air Force destroyed the region's industry in World War II. But the Americans also helped with the reconstruction, and in 1955 the dust precipitation was above pre-war levels. With the onset of motorization, the region and the greater Kyoto area grew together to form a metropolitan area in which over ten million people were affected by air pollution.

Another focus of Japanese pollution was Ube in the northwest, a cement, chemical, and coal center. After scientists from the University of Ube had shown the health effects of air pollution, the fight against air pollution began in 1954 - on the initiative of the chairman of the local industry association, Kanichi Nakayasu! During a visit to Pittsburgh, he realized that the region could solve the problem and advocated strict limits. In 1965 the sky over Ube was blue again; and the city became a model for other regions of Japan (>> more) - In 1968 a law on air pollution control was passed in Japan, in which the local prefects were given the freedom to set limit values.

Soviet Union and Eastern Europe

The >> Soviet industrialization from 1927 onwards repeated the pattern of the West and even surpassed it in terms of environmental pollution - here one could refer to Marx and Engels, who had drawn the image of humans as rulers of nature. It was clear to the leaders of the state how nature could be harnessed in society: production always had priority. Probably the dirtiest steelworks in the world was the Soviet one in Norilsk in Siberia, run by Stalin's secret police and built by Gulag workers: in the 1980s, it emitted more sulfur dioxide than all of Italy. (Norilsk is still one of the ten dirtiest places in the world today, >> more.) The air in Moscow deteriorated from the 1930s onwards, and in the 1960s the levels of sulfur dioxide and nitrogen oxides in some suburbs were far beyond any limit. The situation was even worse in the industrial areas of Donetsk and Magnitogorsk.

After the Second World War, the Soviet model was based on Eastern Europe transfer. One consequence was the creation of the “sulfur triangle” between Dresden, Prague and Krakow. The lignite power stations here generated three quarters of the electricity demand in Poland and two thirds of the demand in Czechoslovakia and the GDR, the concentration of sulfur dioxide in the air exceeded the limit values ​​of the World Health Organization by a factor of twenty. 170 tons of lead and 7 tons of cadmium fell on Krakow every year. The GDR As a result, it developed - somewhat delayed - in a very similar way to the Federal Republic (only that here - see above - the even more environmentally harmful lignite became the basis of the energy industry). The expansion of the chemical industry began at the end of the 1950s: plastics and elastics from Schkopau (advertising slogan for the Buna chemical works) became the basis of industrial production, which was often carried out on equipment from the interwar period. The air in the "chemical triangle" between Merseburg, Halle and Bitterfeld was literally bad: "Bitterfeld, Bitterfeld, where the dirt falls from the sky ...". The five-year plans and the annual plans, which were binding for operational planning, only contained specifications for productivity; a reduction in air pollution was not a target.

Other regions

The other regions where industrialization began all had similar problems: in Brazil, for example, the area around Cubatão in the state of São Paulo was also called the "Valley of Death" - child mortality here was ten times higher than the state average.

Environmental movement and air pollution laws

Germany was not alone with its increasing attention to questions of environmental pollution from the mid-1960s: everywhere in the core countries of industrialization - North America, Europe and Japan - effective popular protests against this pollution began. As shown above, Japan was the first country to enact a nationwide air pollution law. 1966 reminded a smog alarm in New York - of all times Thanksgiving-Fest - the Americans to the London smog; and after the heavily polluted Cuyahoga River caught fire on June 22, 1969, Senator Gaylord Nelson organized the first on April 22, 1970 Earth Day: 20 million Americans demonstrated against pollution that day; especially against air pollution from coal-fired power plants. 20 million people - the signal was so clear that even a conservative government like Richard Nixon's could not fail to hear it: 1970 began with the Clean Air Act the age of modern American environmental law (1250), the Environment Agency Environmental Protection Agency was founded. In Germany, too, the modern development of state environmental protection began with the assumption of office of the social-liberal coalition and the emergence of numerous citizens' initiatives for environmental protection. In 1971 the federal government announced the first environmental program, in 1972 the Basic Law was changed and in 1974 Germany also received the one based on the North Rhine-Westphalian model Federal Immission Control Act (1255) a law on air pollution control. With this law, the licensing requirement for environmentally harmful companies was removed from trade law and transferred to the new law. In the same year, a Federal Environment Agency was founded in Germany.

However, it took some time before the new law on air pollution control could take effect (1258). In the meantime, the distribution of air pollution through high chimneys had become an undeniable problem: smoke and soot as local problems were reduced, but sulfur and nitrogen oxides could spread over thousands of kilometers and formed the main component of "acid rain" which became a >> transnational environmental problem in the 1980s. In Germany, forest damage, for which acid rain was the main cause, became a politically explosive topic under the catchphrase "forest dieback". It became clear: high chimneys are not a solution, emissions had to be reduced. In Germany, an ordinance on the Federal Immission Control Act (1260) issued in 1983 forced the operators of large power plants, who are mainly responsible for sulfur and nitrogen oxide emissions, to install effective filter systems. Together with increased efficiency in the use of energy and the replacement of coal with oil and gas, regulations issued in other countries have now led to significant reductions in sulfur dioxide emissions - in the carbon cities of North America, Western Europe and Japan, smoke, soot and sulfur dioxide levels remained the same as before in London by 70 to 95 percent. The approaches to reducing nitrogen oxide emissions were less successful, and they also contribute to the formation of >> summer smog, which is still a problem in large cities, including in the western world. >> Car traffic is also responsible for this burden.

The Development of the sulfur dioxide concentration in the air in the Rhine-Ruhr area from 1964
until 2005
shows an example of the improvement in air quality in this industrial region since the beginning
of environmental protection activities in the 1960s. (Reliable older values ​​of this in the Ruhr area
for a long time (>> 1235) as "sulphurous acid" (which arises in the air from >> sulfur dioxide)
known cause of severe damage are unfortunately not available. Fig .: see >> 1264.

The protests of the environmentalists, however, found less attention in the non-democratic countries. The situation there only changed after the fall of the respective regimes: In Brazil after the end of the military dictatorship in 1984; in the Soviet Union and the countries of Eastern Europe after the collapse of the Soviet Union in 1991 - here for the most part not through cleaner production, but through the collapse of the economy after the subsidies were no longer available. In India and China, efforts to protect the environment are often not implemented locally (>> more).

The age of oil

Since 1920 coal has been increasingly replaced by oil in the USA and since 1950 in the rest of the world. This had far-reaching consequences: Oil could be transported and used more easily than coal, and therefore the relatively concentrated (but therefore also easier to combat through centralized measures) air pollution from coal combustion was caused by more extensive air pollution from the combustion of (but somewhat cleaner) oil replaced. A symbol of this new age is the car, which replaced the railroad as the No. 1 technical means of transport.

Air pollution from cars

The decisive development was the introduction of the assembly line: it made cars affordable, and mass motorization began - first in the USA, then in Europe and finally in Japan and East Asia. In 1900 automobiles were still a rarity; in 1996 there were 500 million of them worldwide. From the 1960s onwards, they replaced coal firing as the worst cause of pollution. Above all, cars emit carbon monoxide, nitrogen oxides and hydrocarbons, which areSummer smog”Contribute. This has been observed since the 1940s - first in Los Angeles - it occurs when volatile hydrocarbons and nitrogen oxides form ozone under intense solar radiation (>> The most important pollutants).

Tetraethyl lead has been added to gasoline since the 1920s to prevent uncontrolled spontaneous combustion of the gasoline ("knocking"). Over time, this led to high concentrations of lead in the soil along the streets and to increased levels of lead in the blood. Lead is stored in bones and therefore accumulates over time; Chronic lead poisoning can damage blood formation, the nervous system and embryos. In 1967, leaded gasoline was banned in major cities in the Soviet Union, the transition to unleaded gasoline began in the US in the late 1970s, and in Europe in the 1980s. The lead concentration in the air fell in the USA between 1977 and 1994 by about 95 percent, and the values ​​in the blood also fell significantly. (As a parallel to today's resistance to climate protection (>> more), the auto industry announced a mass extinction of engines if lead should be banned; and the first manufacturers to offer engines for unleaded petrol came from Japan the Soviet Union probably facilitated their unusual pioneering role.)

Unleaded petrol was also a prerequisite for the use of catalytic converters, which have been used in recent years to reduce the amount of pollutants in car exhaust. However, part of the progress achieved was canceled out by the increasing number of cars and higher mileage. In other cases, the automotive industry does not consistently implement existing exhaust gas cleaning techniques: Nitrogen oxides, which are mainly formed in diesel engines due to the higher combustion temperatures, can be added using a selective catalytic reduction (SCR) process (known in Germany as "AdBlue") 90 percent can be removed from the car exhaust. In 2003, however, it became known that truck manufacturers were setting their vehicles in such a way that the limit values ​​were exceeded outside of the test cycle; After the VW emissions scandal was uncovered in 2015, it became known that this is also common for cars (in the case of VW even by violating legal regulations [1270]).

Global air pollution

In the second half of the 20th century, air pollution became a cross-border phenomenon. The “politics of high chimneys” played a central role, but also the increasing population and its urbanization: in 1950 there were three metropolitan areas with more than 10 million inhabitants in the world (so-called megacities), in 1997 there were already twenty.

acid rain

In the 1960s, Scandinavian scientists recognized that the acidification of the rivers and lakes of southern Sweden and Norway was caused by sulfur and nitrogen oxides from England ("acid rain", which is caused by the reaction of these substances with water vapor in the atmosphere); Air pollution has been recognized as a global problem. The problem arose from higher chimneys, which alleviated local environmental problems, but allowed the pollutants to rise higher, stay in the atmosphere longer and spread them further. It soon became apparent that the lakes in Canada (through exhaust gases from the USA) and Japan (through exhaust gases from China) were also acidifying. From the 1990s onwards, the sulfur dioxide and nitrogen oxide clouds could then also be recorded directly using measuring instruments on satellites.Acid rain damaged extensive forest areas (“forest dieback”) and the communities of rivers and lakes; he also let limestone and marble deteriorate, which affected some of the most important cultural monuments in the world, but also bridges and other buildings.

With the reduction in emissions of sulfur dioxide and nitrogen oxide, the problem decreased in the West; however, emissions in China are increasing due to increasing coal burning: 60 percent of the country is affected by acid rain, as are Japan, Taiwan, Korea and the Philippines.

The ozone hole

The “CFCs” (chlorofluorocarbons, chemical substances containing fluorine, chlorine and carbon) first produced in 1929 have many good properties: They are non-toxic, non-flammable, easy to process and do not react with other substances. Soon they were mainly used as coolants in refrigerators and air conditioning systems, as propellants in spray cans and as solvents. In 1971 the chemist James Lovelock (see >> here) discovered these CFCs in the atmosphere. Lovelock had only viewed them as markers for other forms of industrial air pollution; he thought CFCs themselves were harmless. The American chemist Sherwood Rowland However, it was noticed that the measured concentrations roughly corresponded to global production up to this point in time. What, he wondered, would eventually happen to them? He continued his colleague from Mexico Mario Molina to the question, and in June 1974 both published the hypothesis that CFCs can rise into the stratosphere, where they are broken up by short-wave sunlight and that the chlorine released in the process destroys ozone molecules in the ozone layer (see >> here).

This contribution was initially almost ignored. The CFC industry was now $ 8 billion a year in sales and attacked Rowland and Molina as alarmists, and over the years it got off the agenda. It was not until 1985 that a publication by the British geophysicist Joe Farman appeared that the Ozone layer thinning over the Antarctic - since 1977. Farman had delayed the publication because he did not really trust his own findings - especially since a NASA satellite had also measured the ozone content for five years and did not detect a decrease. (After Farman's publication, NASA checked their data: the actual satellite data had shown the same trend for years - but had been sorted out by the computer as an error because it did not meet expectations.) The measured decline was even worse than that expected by Rowland and Molina .

Soon “ozone holes” were discovered over Chile and Australia. In 1987, a NASA expedition to Antarctica confirmed the CFCs suspected by Rowland and Molina as the cause. But why the measured decline was so much stronger than that expected by Rowland and Molina was discovered by the Dutch meteorologist working in Germany Paul Crutzen discovered: It was due to the stratospheric ice clouds of the Antarctic. Their surface facilitated reactions in which chlorine was released. This chlorine could then develop its destructive effect with the rising sun in spring - a single chlorine atom can destroy up to 100,000 ozone molecules. (Rowland and Molina as well as Crutzen were to receive the Nobel Prize for Chemistry in 1995 for their research.) The consequences of the thinned ozone layer also became increasingly clear: Increased UV radiation damages plankton and thus the food chain in the oceans, damages plants and thus food production Skin cancer and cataracts in humans.

The “ozone hole” provoked an unusually quick political response: the Montreal Protocol (1987) and the subsequent additional agreements led to a decrease in CFC production of around 80 percent from 1988 onwards. The Montreal Protocol was passed even before the CFC was finally proven as the cause of the ozone hole, so it is the first example of the precautionary principle in environmental protection. On the other hand, they were proof that humans can trigger global environmental changes. And: CFCs are very stable in the atmosphere, so that the ozone layer in the stratosphere only heals slowly and will probably remain thinned until 2070. In particular, fair-skinned people in sunny countries like Australia are affected by a higher risk of skin cancer.

Weblink: >> At the last minute - A contribution by ZEIT to the Montreal Protocol.


In the megacities, people are particularly affected by the effects of smoke and car traffic; According to the World Bank, the ten cities on earth with the worst air quality are Cairo (Egypt), Delhi and Kolkata (Calcutta) in India, Tianjin and Chongqing in China, Kanpur and Lucknow (India), Jakarta (Indonesia) as well as Shenyang and Zhengzhou (Gina). In 2007, the WHO estimated that air pollution kills 865,000 people every year, plus millions of people in whom it caused or worsened respiratory diseases or even caused cancer. The top ten most polluted places on earth, according to the Blacksmith Institute (a private organization that identifies pollution spots and initiates programs to remediate them, are shown on the map below.

The ten most polluted places in the world in 2007. According to the Blacksmith Institute. More information, including about the individual locations, on the website (in English).

Light pollution

Not yet recognized by many as a problem: Light also “pollutes” the environment. A fifth of humanity (including most of the Germans) can no longer see the Milky Way at night because the night sky is outshone by artificial light. The consequences for humans are, in addition to the limited possibilities of observation for amateur astronomers, above all of a spiritual nature (a look at the night sky can show us our place in the universe and could thus perhaps correct some human megalomania); But many animals actually suffer: for example, newly hatched sea turtles run into hotels instead of into the sea, because they are attracted by light (which used to be reflected on the surface of the sea at night and thus pointed in the right direction); Insects and birds fly (“attracted like moths to light”) against brightly lit houses.

On a clear night, the light spots of the cities are on satellite images
clearly visible. Photo: NASA

The remedy would be simple: For outdoor lighting, there have long been lamps that only shine downwards. After all, there is slowly growing awareness of the problem: The US has the first dark sky parks, the English one Peak District National Park applies for such a title.

The consequences of air pollution

There are no reliable statistics from the early days of industrialization; the possible consequences of air pollution only became of interest from the 1950s onwards. But the figures from the Eastern European cities that became available after the collapse of the Soviet Union and whose burden is similar to that of early industrial cities can give an impression: In Upper Silesia the child mortality rate was 44 out of 1,000 children and three quarters of all ten-year-old children needed constant medical treatment. Life expectancy in the Czech industrial areas was 4 years below the average.

There are estimates according to which air pollution claimed a total of 40 million lives in the 20th century; according to estimates by the World Health Organization, 865,000 people are currently added each year, mainly in emerging and developing countries - although the air quality has improved overall, the pollution is hit more people. After more than 30 years of environmental policy, on the other hand, the most obvious pollution in the rich industrialized countries has now been eliminated and the air we breathe is relatively clean again. Even if individual problems (>> nitrogen oxides, >> fine dust; see also >> chemicals in the environment) remain acute: The biggest problem here today is the not immediately recognizable pollution such as >> climate change, which occurs around the same time as the Ozone hole has come into the public eye - probably the most important environmental issue of the coming decades. Since the necessary measures also affect the industries of developing and emerging countries (>> more), their implementation would also reduce air pollution.

Further to:
>> Climate change

Back to:
>> Overview of the industrial age

© Jürgen Paeger 2006 - 2020


More on this topic on the page: >> The most important air pollutants.

The "classic" smog of London type is now also called Winter smog to distinguish it from the "modern" >> summer smog.

The Russian physicist was awarded for her efforts to clear up the Soviet legacy in the successor states Olga Speranskaya from the environmental organization Eco-Accord Center (>> website) in 2009 among other things one Goldman Prize and was dated Time magazine to the Hero of the Environment chosen.