Tehran
Tehran (; , ''Tehrân'') is the capital and largest city of Iran. It is the capital of Tehran province, and the administrative center for Tehran County and its Central District (Tehran County), Central District. With a population of around 9. ...
, the capital city of
Iran
Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...
, suffers from severe
air pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
, and it is located near three major
fault lines, while being the most populous region of the country. The
officials
An official is someone who holds an office (function or mandate, regardless of whether it carries an actual working space with it) in an organization or government and participates in the exercise of authority (either their own or that of the ...
have created financial incentives to encourage around 5 million
citizens
Citizenship is a membership and allegiance to a sovereign state.
Though citizenship is often conflated with nationality in today's English-speaking world, international law does not usually use the term ''citizenship'' to refer to nationality; ...
to leave the city. On December 16, 2019
Tehran
Tehran (; , ''Tehrân'') is the capital and largest city of Iran. It is the capital of Tehran province, and the administrative center for Tehran County and its Central District (Tehran County), Central District. With a population of around 9. ...
had its highest air pollution index of 181.
Air pollution

Tehran is rated as one of the world’s most polluted cities. Parts of the city are often covered by
smog
Smog, or smoke fog, is a type of intense air pollution. The word "smog" was coined in the early 20th century, and is a portmanteau of the words ''smoke'' and ''fog'' to refer to smoky fog due to its opacity, and odour. The word was then inte ...
, making breathing difficult and causing widespread pulmonary illnesses. It is estimated that about 27 people die each day from
pollution-related diseases. According to local officials, 3,600 people died in a single month due to the hazardous
air quality. 80% of the city's pollution is due to cars. The remaining 20% is due to
industrial pollution. Other estimates suggest that motorcycles alone account for 30% of air and 50% of
sound pollution in Tehran.
In 2007, Iran
imposed fuel rations but the plan has met little success in reducing the pollution levels. In 2011, with the improvements in the public transport system and the rise in fuel prices due to the new
subsidies reform plan, the
government
A government is the system or group of people governing an organized community, generally a State (polity), state.
In the case of its broad associative definition, government normally consists of legislature, executive (government), execu ...
is hoping to be able to improve the problems of pollution and traffic.
The air pollution is due to several different reasons:
*
Economical
An economic system, or economic order, is a system of production, resource allocation and distribution of goods and services within an economy. It includes the combination of the various institutions, agencies, entities, decision-making proces ...
: most Iranian industries are located on the outskirts of Tehran. The city is also overrun with old and aging cars which do not meet today's emission regulations. Furthermore, Iran's busiest airport,
Mehrabad International Airport
Mehrabad Interglobal Airport is an airport serving Tehran, the capital of Iran. Prior to the construction of the larger Imam Khomeini International Airport in 2007, Mehrabad was Tehran's primary airport for both international and domestic tr ...
, is located in the west of the city.
*Most people are then obliged to either use private cars or hire taxis. This has created severe
traffic congestion
Traffic congestion is a condition in transport that is characterized by slower speeds, longer trip times, and increased vehicular queueing. Traffic congestion on urban road networks has increased substantially since the 1950s, resulting in m ...
;
*Gasoline quality: Due to
international sanctions
International sanctions are political and economic decisions that are part of diplomatic efforts by countries, multilateral or regional organizations against states or organizations either to protect national security interests, or to protect i ...
, the Iranian government allowed its refineries (designed to produce petrochemical products) to manufacture sub-par gasoline.
*Geographical: Tehran is bound in the north by the massive Alborz mountain range that is stopping the flow of the humid
Caspian wind. As a result,
thermal inversion
In meteorology, an inversion (or temperature inversion) is a phenomenon in which a layer of warmer air overlies cooler air. Normally, air temperature gradually decreases as altitude increases, but this relationship is reversed in an inver ...
that traps Tehran's polluted air is frequently observed. The lack of humidity and clouds makes Tehran a very sunny city. The UV radiations then combined with the existing pollutants significantly raise the level of the
ozone
Ozone () (or trioxygen) is an Inorganic compound, inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , break ...
. In fact one of the urban landmarks in central Tehran is a giant air quality gauge.
However, the government is engaged in a battle to reduce air pollution. It has, for instance, encouraged taxis and buses to convert from
petrol engines to engines that run on
compressed natural gas
Compressed natural gas (CNG) is a fuel gas mainly composed of methane (CH4), compressed to less than 1% of the volume it occupies at standard atmospheric pressure. It is stored and distributed in hard containers at a pressure of , usually in ...
. Furthermore, since 1979, the government has set up a "Traffic Zone" covering the city center during peak traffic hours. Entering and driving inside this zone is only allowed with a special permit.
The government is also trying to raise people's awareness about the hazards of the pollution. One method that is currently being employed is the installation of Pollution Indicator Boards all around the city to monitor the current level of
particulate matter
Particulate matter (PM) or particulates are microscopic particles of solid or liquid matter suspended in the air. An ''aerosol'' is a mixture of particulates and air, as opposed to the particulate matter alone, though it is sometimes defin ...
(PM10),
nitrogen dioxide
Nitrogen dioxide is a chemical compound with the formula . One of several nitrogen oxides, nitrogen dioxide is a reddish-brown gas. It is a paramagnetic, bent molecule with C2v point group symmetry. Industrially, is an intermediate in the s ...
(NO
2), ozone (O
3),
sulfur dioxide
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is r ...
(SO
2), and
carbon monoxide
Carbon monoxide (chemical formula CO) is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the si ...
(CO). The board also displays the
Pollutant Standards Index
The Pollutant Standards Index (PSI) is a type of air quality index used in Singapore, which is a number used to indicate the level of pollutants in air. Initially PSI was based on five air pollutants, but since 1 April 2014 it has also include ...
(PSI), which is a general indication of air quality based on the measurements of the above-mentioned five pollutants. The Pollution Indicator Boards classify the level of each pollutant as either safe, hazardous or dangerous.
In January 2017,
Al Arabiya
Arabiya (, transliterated: '; meaning "The Arabic One" or "The Arab One") is a Saudi state-owned international Arabic news television channel. It is based in Riyadh and is a subsidiary of MBC Group.
The channel is a flagship of the media c ...
reported that pollution in Tehran has hit a dangerous level on the Air Quality Index.
On February 5, 2018 the Air Pollution Monitoring Center announced the air pollution index of the capital as 161 which is in the red zone.
Earthquake
Tehran sits on two major fault lines, and it has been hit by over 1000 big and small earthquakes; although, the region has not been hit by a severe earthquake in the last 150 years.
The city has been rapidly growing, and many buildings have been constructed without enough earthquake readiness. This is while there has been a 90% chance of an extent 6.0 or greater earthquake in the coming decades.
Capital relocation
In 2010, the government announced that "for security and administrative reasons, the plan to move the capital from Tehran has been finalized."
The
Iranian Parliament
The Islamic Consultative Assembly (), also called the Iranian Parliament, the Iranian Majles (Arabicised spelling Majlis) or ICA, is the unicameral national legislative body of Iran. The parliament currently consists of 290 representatives, an i ...
named
Shahroud
Shahrud ( , also written as: shahrood , shahroud) is a city in the Central District of Shahrud County, Semnan province, Iran, serving as capital of both the county and the district.
History
Archeological excavations in different parts o ...
,
Esfahan and
Semnan as three of the main candidates to replace Tehran as the capital. There are plans to relocate 163 state firms to the
provinces
A province is an administrative division within a country or state. The term derives from the ancient Roman , which was the major territorial and administrative unit of the Roman Empire's territorial possessions outside Italy. The term ''provi ...
and several
universities
A university () is an educational institution, institution of tertiary education and research which awards academic degrees in several Discipline (academia), academic disciplines. ''University'' is derived from the Latin phrase , which roughly ...
from Tehran to avoid damages from a potential
earthquake
An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they ...
.
See also
*
Environmental issues in Iran
*
Geography of Iran
Geographically, the country of Iran is located in West Asia and the bodies of water the nation borders are the Caspian Sea, Persian Gulf (Persian Gulf), and Gulf of Oman. Topographically, it is predominantly located on the Iranian plateau, Iran ...
*
List of earthquakes in Iran
Iran is one of the most seismically active countries in the world, being crossed by several major faults that cover at least 90% of the country. As a result, earthquakes in Iran occur often and are destructive.
Geology and history
The Irania ...
References
{{reflist, 30em
Tehran
Environmental issues in Iran