World's Most Polluted Cities
February 28, 1999 - 0:0
MEXICO CITY, Mexico ----With a population of 18 million people Mexico City is one of the most populated cities in the world. With 3.4 million vehicles on the capital's streets, exhaust fumes are the number one cause of pollution. Winter months are the worst for the smog with cool, dry conditions working to trap warmer polluted air in the bowl-shaped valley 7,350 feet (2,250 meters) above sea level.
The frequent high pollution conditions cause authorities to declare state of smog emergencies banning private vehicles from the streets. About one third of the capital's population suffers respiratory problems during smog alerts. Aside from exhaust fumes, the air is polluted with fumes from factories and sewage. The city is Mexico's biggest industrial center. Forest and brush fires across Mexico aggravate the city's pollution levels.
The authorities have imposed stricter emission controls on taxis and buses, and ban 50 percent of cars especially the older models during smog alerts. DHAKA, Bangladesh Authorities in Bangladesh have identified emission from automobiles, specifically the two-stroke engines used in three-wheeler auto-rickshaws, combined with the use of leaded fuel responsible for 80 percent of Dhaka's air pollution. A city of 9 million people Dhaka is polluted by leaded exhausts from nearly 175,000 motor vehicles, including more than 40,000 auto-rickshaws.
Major Bangladesh cities are among the world's most polluted. Public exposure to air pollution in Dhaka is estimated to cause 15,000 premature deaths and several million cases of sickness every year. Recently tests on children revealed levels of lead in blood of between 93-200 micrograms. World Health Organization's (WHO's) recommendation are 25 micrograms per one deciliter. Lead can retard the mental and physical development of children.
As a result the government has put a ban on imported leaded fuels and will introduce catalytic converters. As well plans are laid to phase out auto-rickshaws by 2001. The World Bank has announced the approval of $177 million to help solve Dhaka's traffic and air pollution. NEW DELHI, India The city has a rising number of aging buses, auto-rickshaws, cars and fires on the roadside used by laborers for cooking and keeping themselves warm.
These are the reasons why the Indian capital is fast becoming one of the world's most polluted cities. A city of roughly 12 million people, there are now 3.3 million cars, trucks, buses and scooters compared to slightly over 500,000 vehicles in 1980. These vehicles account for 64 percent of pollution. The levels of benzene, a known carcinogen, are 20 times what is deemed safe.
Burning of leaves by laborers to keep warm in winter and autumn and to cook is a major source of pollution. Estimates show 100-150 tones of leaves are burnt in autumn and the figure reaches 150-200 tones in winter despite a government ban. Mixing of kerosene with diesel to cut fuel costs makes the problem even harder to deal with by the law-makers.
Poor visibility caused by the heavy fog grounds many planes from taking off at the airport spoiling many people's holiday or business plans. As a result there are a number of oxygen bars emerging in the city. For 200 rupees ($4.7), close to three times New Delhi's daily minimum wage, customers can snort 93-percent pure oxygen for half an hour through plastic tubes inserted into their nostrils.
As many as 2.5 million people nation-wide die each year from illness related to pollution. The toll is expected to go up. CAIRO, Egypt The suffocating cocktail of gases emitted by the city's 1.2 million vehicles two-third of them aging and badly maintained is the second biggest pollutant after emissions from some 800 factories around the city. Dust from the surrounding desert adds to the woes of the capital's 15 million residents.
Under a government sponsored project since January 1996 some 11,000 vehicles, mainly taxis, have converted their engines to work with inexpensive natural gas instead of gasoline. The conversion costs 5,000 Egyptian Pounds ($1,473) which will be more than compensated in the long run due to the cheaper price of natural gas. Industry experts are hailing Egypt's experience as a valuable lesson for fighting air pollution cheaply and safely.
With known gas reserves of 1 trillion cubic meters (36 trillion cubic feet), sufficient to last at least 20 years. The commercial use of compressed natural gas started in 1996, when Egypt also banned leaded gasoline. Natural gas engines emit virtually no carbon monoxide and very little of other noxious fumes that gasoline fueled cars spew. BEIJING, China Despite the officials imposing draconian measures to stop the rot, Beijing's 13 million people are choking in what has become one of the most polluted cited in the world in a matter of just a few years.
Two out of every three days of smog was recorded last year with very little signs of blue sky and sun. Smog has steadily worsened since the early 1980's as China's economic transformation came into force and traffic rapidly increased in the capital. Largely to blame are 18 million tons of coal burned by Beijing residents every year for heating, and emissions from 1.4 million cars, which together account for 80 per cent of lead emissions, 63 percent of carbon monoxide and 37 percent of nitrogen oxide.
The cars in Beijing are comparable to the ones running in United States in 1970s. The trucks and the public transport vehicles are largely old and diesel powered. Acid rain is a direct result of coal-burning, still China's main source of energy, which produces highly polluting soot and sulfur dioxide. China is the second largest emitter of sulphur dioxide in the world.
Acid rain, which now affects some 30 percent of China's territory has hindered economic development by decreasing grain, vegetable and fruit production. As well severe water shortages, due to pollution, threaten the survival of the world's most populous nation. HONG KONG, China According to study, by the Hong Kong University's Center for Urban Planning and Environment Management, the city faces environmental disaster unless urgent action is taken to clean up its air, water and rubbish disposal.
The dirty water, killing tons of fish devastating the fish farming industry, is also due to an ineffective sewage disposal system. A growing population is responsible for rapidly mounting piles of garbage, which requires a safe landfill area to accommodate. Some 80 percent of the city's fish stocks are estimated to have been destroyed. Most of the air pollution is from motor vehicle emissions.
Hong Kong has a large number of diesel vehicles, mostly taxis and buses, adding to the city's pollution problem. BEIRUT, Lebanon Motor vehicles, many up to 18 years old, and congested roads in and around the capital, where about half of Lebanon's 3.2 million people live, are the main culprits behind the pollution. There are about 1.8 million vehicles on the road in Lebanon, most of them in the streets of Beirut. This indicates a very high ratio of vehicles to the population.
In 1975 there about 300,000 vehicles in Lebanon. Gas emissions from motor vehicles and factories are costing Lebanon annually $450 million in lost productivity, health and environmental damage, according to a report carried by An-Nahar newspaper. This amounts to 3.5 percent of the gross domestic product, higher than the European average of about 2 percent. Some commonalties to be found among the above cities: a) They are the capitals and as well the countrys' major industrial sites.
Combining the two factors we invite concentration of most of the factories along with the bureaucracies in one place. This is not a healthy combination and is a malpractice. Some countries, such as Canada, Pakistan, etc., have successfully avoided this by keeping the capital and industrial sites separate. b) Emissions from vehicles is the major cause of the air pollution. Abundance of old cars on the street further deteriorates the situation.
c) Use of unclean forms of energy, e.g. using coal for heating households and factory furnaces or diesel to fuel trucks and buses. Today scientists are looking for life in Mars and moons of Jupiter. If some action is not taken in the near future about pollution in these cities it would make the job of these scientists much easier. Their search for life would not involve sending probes to such distant planets and moons, rather it would start in the capitals of the developing world.
The frequent high pollution conditions cause authorities to declare state of smog emergencies banning private vehicles from the streets. About one third of the capital's population suffers respiratory problems during smog alerts. Aside from exhaust fumes, the air is polluted with fumes from factories and sewage. The city is Mexico's biggest industrial center. Forest and brush fires across Mexico aggravate the city's pollution levels.
The authorities have imposed stricter emission controls on taxis and buses, and ban 50 percent of cars especially the older models during smog alerts. DHAKA, Bangladesh Authorities in Bangladesh have identified emission from automobiles, specifically the two-stroke engines used in three-wheeler auto-rickshaws, combined with the use of leaded fuel responsible for 80 percent of Dhaka's air pollution. A city of 9 million people Dhaka is polluted by leaded exhausts from nearly 175,000 motor vehicles, including more than 40,000 auto-rickshaws.
Major Bangladesh cities are among the world's most polluted. Public exposure to air pollution in Dhaka is estimated to cause 15,000 premature deaths and several million cases of sickness every year. Recently tests on children revealed levels of lead in blood of between 93-200 micrograms. World Health Organization's (WHO's) recommendation are 25 micrograms per one deciliter. Lead can retard the mental and physical development of children.
As a result the government has put a ban on imported leaded fuels and will introduce catalytic converters. As well plans are laid to phase out auto-rickshaws by 2001. The World Bank has announced the approval of $177 million to help solve Dhaka's traffic and air pollution. NEW DELHI, India The city has a rising number of aging buses, auto-rickshaws, cars and fires on the roadside used by laborers for cooking and keeping themselves warm.
These are the reasons why the Indian capital is fast becoming one of the world's most polluted cities. A city of roughly 12 million people, there are now 3.3 million cars, trucks, buses and scooters compared to slightly over 500,000 vehicles in 1980. These vehicles account for 64 percent of pollution. The levels of benzene, a known carcinogen, are 20 times what is deemed safe.
Burning of leaves by laborers to keep warm in winter and autumn and to cook is a major source of pollution. Estimates show 100-150 tones of leaves are burnt in autumn and the figure reaches 150-200 tones in winter despite a government ban. Mixing of kerosene with diesel to cut fuel costs makes the problem even harder to deal with by the law-makers.
Poor visibility caused by the heavy fog grounds many planes from taking off at the airport spoiling many people's holiday or business plans. As a result there are a number of oxygen bars emerging in the city. For 200 rupees ($4.7), close to three times New Delhi's daily minimum wage, customers can snort 93-percent pure oxygen for half an hour through plastic tubes inserted into their nostrils.
As many as 2.5 million people nation-wide die each year from illness related to pollution. The toll is expected to go up. CAIRO, Egypt The suffocating cocktail of gases emitted by the city's 1.2 million vehicles two-third of them aging and badly maintained is the second biggest pollutant after emissions from some 800 factories around the city. Dust from the surrounding desert adds to the woes of the capital's 15 million residents.
Under a government sponsored project since January 1996 some 11,000 vehicles, mainly taxis, have converted their engines to work with inexpensive natural gas instead of gasoline. The conversion costs 5,000 Egyptian Pounds ($1,473) which will be more than compensated in the long run due to the cheaper price of natural gas. Industry experts are hailing Egypt's experience as a valuable lesson for fighting air pollution cheaply and safely.
With known gas reserves of 1 trillion cubic meters (36 trillion cubic feet), sufficient to last at least 20 years. The commercial use of compressed natural gas started in 1996, when Egypt also banned leaded gasoline. Natural gas engines emit virtually no carbon monoxide and very little of other noxious fumes that gasoline fueled cars spew. BEIJING, China Despite the officials imposing draconian measures to stop the rot, Beijing's 13 million people are choking in what has become one of the most polluted cited in the world in a matter of just a few years.
Two out of every three days of smog was recorded last year with very little signs of blue sky and sun. Smog has steadily worsened since the early 1980's as China's economic transformation came into force and traffic rapidly increased in the capital. Largely to blame are 18 million tons of coal burned by Beijing residents every year for heating, and emissions from 1.4 million cars, which together account for 80 per cent of lead emissions, 63 percent of carbon monoxide and 37 percent of nitrogen oxide.
The cars in Beijing are comparable to the ones running in United States in 1970s. The trucks and the public transport vehicles are largely old and diesel powered. Acid rain is a direct result of coal-burning, still China's main source of energy, which produces highly polluting soot and sulfur dioxide. China is the second largest emitter of sulphur dioxide in the world.
Acid rain, which now affects some 30 percent of China's territory has hindered economic development by decreasing grain, vegetable and fruit production. As well severe water shortages, due to pollution, threaten the survival of the world's most populous nation. HONG KONG, China According to study, by the Hong Kong University's Center for Urban Planning and Environment Management, the city faces environmental disaster unless urgent action is taken to clean up its air, water and rubbish disposal.
The dirty water, killing tons of fish devastating the fish farming industry, is also due to an ineffective sewage disposal system. A growing population is responsible for rapidly mounting piles of garbage, which requires a safe landfill area to accommodate. Some 80 percent of the city's fish stocks are estimated to have been destroyed. Most of the air pollution is from motor vehicle emissions.
Hong Kong has a large number of diesel vehicles, mostly taxis and buses, adding to the city's pollution problem. BEIRUT, Lebanon Motor vehicles, many up to 18 years old, and congested roads in and around the capital, where about half of Lebanon's 3.2 million people live, are the main culprits behind the pollution. There are about 1.8 million vehicles on the road in Lebanon, most of them in the streets of Beirut. This indicates a very high ratio of vehicles to the population.
In 1975 there about 300,000 vehicles in Lebanon. Gas emissions from motor vehicles and factories are costing Lebanon annually $450 million in lost productivity, health and environmental damage, according to a report carried by An-Nahar newspaper. This amounts to 3.5 percent of the gross domestic product, higher than the European average of about 2 percent. Some commonalties to be found among the above cities: a) They are the capitals and as well the countrys' major industrial sites.
Combining the two factors we invite concentration of most of the factories along with the bureaucracies in one place. This is not a healthy combination and is a malpractice. Some countries, such as Canada, Pakistan, etc., have successfully avoided this by keeping the capital and industrial sites separate. b) Emissions from vehicles is the major cause of the air pollution. Abundance of old cars on the street further deteriorates the situation.
c) Use of unclean forms of energy, e.g. using coal for heating households and factory furnaces or diesel to fuel trucks and buses. Today scientists are looking for life in Mars and moons of Jupiter. If some action is not taken in the near future about pollution in these cities it would make the job of these scientists much easier. Their search for life would not involve sending probes to such distant planets and moons, rather it would start in the capitals of the developing world.