The document discusses the 1997 air pollution episode in Dhaka, Bangladesh. It notes that Dhaka has extremely high levels of air pollutants that exceed international standards. Major sources of pollution include vehicles, brick kilns burning hazardous materials, and a growing population. High concentrations of particulate matter, sulfur dioxide, lead, and other pollutants have caused many health issues for residents such as respiratory diseases and cancer. Immediate action is needed to improve emissions controls, transportation systems, and increase green spaces to address Dhaka's severe air pollution problems.

1. AIR POLLUTION EPISODE
DHAKA-AIR POLLUTION EPISODE
(1997)
ARSENIC POISONING IN
BANGLADESH/INDIA

2. 2 AirPollutionEpisode
Submittedby:-
Sadia Rahat
Table of
contents
No# CONTENTS Pg
No#
1 Dhaka Air Pollution Episode
Introduction
 Air
 Air Pollution Episode
3

3. 3 AirPollutionEpisode
2 History
 Population of Dhaka
 Report of Air Monitoring Station
 Out Burst of Air Born Diseases
3
3 Root Causes and Effects
 Conc. of Air Pollutants in Dhaka
 Conc. of Lead
 Conc. of PM
 Conc. of Oxides of Carbon
 Conc. of Ozone
 Conc. of sulpher
 Conc. of VOCs
4
4 Sources 6
5 Conclusion 6
6 Solution 7
7 References 7
Dhaka air pollution episode:-
Introduction:-
Air:-
Air is the most integral part of the physical environment, as it
Sustains life of both plant and animals.
Animals take the oxygen from the air and giving out the
carbon dioxide similarly plants take the
carbon dioxide while giving out the oxygen during
photosynthesis. Both land and aquatic ecosystems
are naturally interrelated through direct participation
of air, an invisible ocean. Degradation of the

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environmental quality specially due to the anthropogenic
activities has become popular all over the world .
* Arial view of Dhaka city
Air Pollution Episode:-
A period of abnormally high concentration of air pollutants, often due to low winds and temperature
inversion that can cause illness and death.
Environmental impacts of air pollution include damage to buildings and structures, agricultural crops,
vegetation and forests and reduced visibility. Air quality in Dhaka is a serious issue in view
of the magnitude of its health and economic impacts. Although some measures have already
been taken to improve the air quality in Dhaka but still it is not sufficient.
History:-
Population of Dhaka:-
Dhaka Statistical Metropolitan Area has now extended to more than double the area of what exist in
1981. It is thought that by the end of century it will obtain 11.2 million population that will rank
seventeenth mega city of the world. Unplanned growth of Dhaka city has already created adverse
ecological effects. According to Asian Development Report 1998, Dhaka is the most polluted cities of
the world. Ambient air pollution of Dhaka city has made a world record, abominably, as a number one
pollutant breaking earlier record of Mexico City.
Report of air monitoring stations:-
Althoughthere are many quantitative air monitoring stations in Dhaka but a few scatters studies show
the alarming situation. The report describes that Suspended Particulate Matter (SPM) in the air is
between 1000 and 2000 microgram, 4 to 5 hundred per cent higher than acceptable level. The size,
shape, and density of an airborne particle determine how long a particle will remain in the atmosphere,
whether or not it will be inhaled, and where it may be deposited in the respiratory tract. The solubility
of a gas determines (in part) whether it will cause upper airway irritation or pulmonary edema. The
particulate material can also absorb gases (including sulphur dioxide and formaldehyde) on its surface.
The rate of Brick producing plants increased in Dhaka and the brick producers use the “used oil” for
the combustion in the kilns. The "used oil" is one of the most hazardous wastes that cost millions of
dollars for disposal in the industrial countries. Thathazardous oil imported from the industrial countries.
The old- oils extracted from transformer oils, hydraulic fluids, automobiles and the like are sold locally
named "Maita Tel" or "soil-oil" and used in households as insecticide for protecting wood or metal from
rust.

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Outburst of airborne disease:-
Air pollution episode in Dhaka causes a number of
diseases ranging from skin diseases to cancer. Numerous
ailments are being seen as a result of present
environmental disorder such as:
 Eye irritant
 Severe headache
 Amonexia
 Disruption of blood circulation
 Respiratory problem
 Fatal diseases that may lead to death
*Dhaka, the most polluted city of world
Root causes and Effects:-
Conc. Air pollutants in Dhaka:-
Bangladesh Atomic Energy Commission reports that:
 The highest acceptable level of Sulphur dioxide (S02) is 60 microgram per cubic meter of
air. But it has been recorded at 300 to 500 microgram in Dhaka.
 Automobiles in Dhaka emit 100 kg lead
 3.5 ton suspended particulate matter
 1.5 ton Sulphur Dioxide
 14 ton hydrocarbon
 60 ton Carbon Monoxide
Conc. Lead in ambient air of Dhaka:-
Concentration of lead in ambient air of Dhaka city has been
marked as world's record of 463 nanogram per cubic meter.
Motor vehicles are the main source of lead in the atmosphere.
Children are particularly susceptible to the neurotoxic effects of
lead as the high concentration of lead causes the brain damage
and deformation of bones.
Conc. of Particulate Matter:-
The average suspended particle leads to particulate matter (PM)
rises as high as 227 mg per cubic meter, whereas according to
WHO yearly maximum average value should range between 60-
90 mg per cubic meter.
o Inhalable Particulate Matter (IPM):
Particles that are size less than 15 µm can enter
the tracheobronchiole and gas exchange regions of the *Average conc. is about 7 µg/m
3
lungs,
and thus more likely than Total Suspended and the maxi conc. is 23 µg/m
3
Particulate to produce pollution-related health effects.
o Fine Particulate Matter(FPM):
The particles of <2.5 micrometer in diameter are called the fine particulate matter and their high
concentration causes asthma and other lung diseases.

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Oxides of Carbon in ambient air of Dhaka:-
Carbon monoxide is produced during incomplete
combustion of fossil fuels. Carbon monoxide is present in
10 mg/m
3
to 40 mg/m
3
in ambient air of Dhaka. Carbon
monoxide is basically hinders the oxygen transportation
from blood into tissues.
Conc. of Ozone in Dhaka:-
Ozone is generally short lived at ground level. But once
formed, the reservoir can replenish Ozone at ground level
for 2 or 3 days. The toxic effects of Ozone in the lower
regions of the respiratory tract increase with increased
minute respiratory volume. Animal and human test
*Average conc. of CO is 0.04ppm but
exposed to Ozone shows pulmonary injury and in Dhaka it’s maxi conc. is 0.2ppm
pulmonary function decreases ranging from
12.6 to 20.7 per cent. There are number of diseases cause
by ozone such as:
 Respiratory
 Asthma
 Eye irritation
 Heart attack
Conc. of Sulpher Dioxide in Dhaka:-
Concentration of sulpher dioxide in Dhaka is about 80
ug/m
3
in residential areas and 100 ug/m
3
commercial areas.
Majority of the sulpher dioxide that is about 472.9 ug/m
3
exhaust from the commercial areasandthe rest that is about
63.5 ug/m
3
releases from the residential areas. *Average conc. of O3 is 3ppb
There are many diseases cause by sulpher dioxide but maxi conc. is 9ppb
such as:
 Respiratory diseases
 Chest pain
 Premature mortality
Conc. of Volatile Organic Compounds:-
Significant quantities of VOCs are emitted into the atmosphere through the use of liquid fuels and
through the transport, storage,transfer of organic solvents. Some of the VOCs are describes below such
as:
 Dioxins
 Vinyl chloride
 Methylene chloride
 Trichloroethylene
 Perchloroethylene
 Benzene
 Toluene
 Xylene

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A significant number of VOCs are associated with chronic health problems in the workplace, including
various forms of cancer.
Sources:-
 Acidification of soils and water has created diverse damage to ecological system. Acidification
causes:
 Less organic content in soil
 Increase solubility of hazardous metals like aluminum
 Threatening condition of aquatic organisms
 Essential metals and nutrients are leached out to ground water
 Loss of vegetation
 Lead added gasoline cars with the name of reconditioned cars were sold out in Dhaka market,
almost 200,000 such harmful vehicles played in Dhaka causing the threatening condition for
inhabitants.
 Three wheelers or two-stroke engine (auto-rickshaws)
driven vehicles emit poisonous gases as these engine have
very low efficiency to burn hydrocarbon. Such vehicle
causes the tumors and respiratory diseases like lung cancer
or
 More than 80 per cent of the vehicles of the city were totally
unfit for moving according to department of Environment in
1988.
 Brick producing plants in Dhaka produce the worst
hazardous emissions of this planet as they use trees, coal of
very low quality ( more than 10 per cent sulphur), used tyres
(contain PCB ) and used oil to obtain optimal temperature
for burning bricks. *Open dumping of solid waste
 Brick producing plants causes the destruction of valuable
topsoil and palm and bamboo
trees of the country.
Conclusion:-
 It is conclude that ambient air of Dhaka has become a deadly pollutant and it can be declared as one
of the worst polluted cities of the world. Dhaka with 200,000 vehicles has been marked as world
record of 463 nanogram (one part of a billion) leaded vehicles.
 The Harmful destruction of the greeneryis the major attribute of tragic level of pollution in the city.
 Vanishing of green lands and the expansion of cities or unplanned concrete structures causes the
threatening condition for life in Dhaka.
 Brick fields cause the worst condition for ambient life in Dhaka.
 Two stroke vehicles and use of re-used oil in motor vehicles and brick fields are the major cause of
SOX and NOX in the city.
Solution:-

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 The Government of Bangladesh forms the following policies, acts and guidelines that directly or
indirectly address environmental damaging industrial operation.
 Environment Conservation Act, 1995
 Environment Court Act, 2000
 Environment Conservation Rules 1997
 EIA guideline for industries, 1997
 Factories Act, 1939
 Immediate actions are needed to be taken for the betterment of the air quality in Dhaka such as:
 Prevention of emission at source
 Use of compressed natural gas (CNG) instead of petrol or diesel
 Improve mass transport service
 Ban two-stroke engine
 Use of natural gas for burning in the Brick-fields
 Improve planting activates in the city
*Slum areas of Dhaka *Worst polluted lakes *Population explosion in Dhaka
References:-
 http://www.caslab.com/Air_Pollution_Episode_Meaning/
 http://www.sos-arsenic.net/english/environment/dhaka-air.html
 http://www.flickr.com/photos/mrhasan/5640403396/
 www.rrcap.unep.org/reports/soe/dhaka-soe-05/3-1dhaka-air.pdf
 http://factspy.net/top-10-most-polluted-places-around-the-world/
 http://nagoya-u.academia.edu/MuntaseerBillah/Papers/