written about Air and water pollution.

1. Dhaka school of Economics
University of Dhaka
An assignment on Air pollution and water pollution in Bangladesh
Submitted by: Nahin Mahfuz Seam.
Class : BEcon 1st
batch
Id no : 160121005
Roll no : 09
Subject : Environmental studies
Course ID : 103
Submitted to: Dr. Salma Sultan,
Assistant professor, DScE

2. Air pollution
Air Pollution contamination of the atmosphere caused by the discharge, accidental or
deliberates of a wide range of toxic substances. Often the amount of the releasedsubstance
is relatively high in a certain locality, so the harmful effects are more noticeable. The major
sources of air pollution are transportation engines, power and heat generation, industrial
processes and the burning of solid waste. A new source of air pollution is an increasing
'hole' in the ozone layer in the atmosphere above Antarctica, coupled with growing
evidence of global ozone depletion. Air pollution has also long been known to have an
adverse effect on human beings, plants, livestock and aquatic ecosystemthrough acid rain.
Air pollution can be defined as any atmospheric condition in which substances (natural or
man-made chemical compounds capable of being airborne) are present at concentrations
high enough above their normal ambient level to produce a measurable effect on man,
animals, vegetation, or materials. Air pollutants are hazardous to human health and at
high enough concentrations can evenbe fatal. The most important pollutants are Carbon
monoxide (CO), Sulfur dioxide (SO2), Nitrogen oxides (NOx), Ozone (O3), Hydrocarbons
(HC) and Suspended Particulate Matter (SPM). In the late 1970s, Environmental
Protection Agency (EPA) of USA added lead (Pb) to this list. Particulate matter with an
aerodynamic diameter of less than or equal to 10µm (PM10) was added to the list in 1987.
Air pollution can cause drowsiness, eye irritation, throat irritation, persistent cough,
asthma, nose blockage, respiratory infections, bronchial infections, colds and headaches in
human being. Lead in air can affect the central nervous system, cause renal damage and
hypertension. CO in air reduces the ability of blood to carry oxygen and exacerbates heart
disorders. Dhaka, one of the mega cities of the world, witnessed a very fast growth of urban
population in recent times. Air pollution in Dhaka city is reported to be serious and
damaging to public health. In the winter of 1996-97, air pollution of Dhaka city became the
severest when lead in the air was reported higher than in the atmosphere of any other place
of the world [1]. Concern over air pollution rate of Dhaka city ultimately led to the
promulgation of National Ambient Air Quality Standards in Bangladesh in 1997. A study
of impact of auto-exhaust on air quality of Dhaka city has been conducted in the year 2000,
it is revealed that traffic congestion, fuel quality and brick field emission are the main
reasons of air pollution in Dhaka city [2]. To control air pollution level CNG at large scale
has introduced in Dhaka city. Air quality of Dhaka city after large scale introduction of
CNG vehicles has been studied in this investigation. As people spend most of their time
indoors and the concentrations of pollutants may build up in an enclosed space, the risk to

3. health may be greater to exposure to air pollution indoor than outdoor. For the first time,
indoor air pollution level of Dhaka city has also been assessedsystematically during this
study. Brick field emission level data have also presented. In this paper the results of
investigation on air quality of Dhaka city have been assessedand put forward some
recommendations.
Recently as in other parts of the world air pollution has received priority among
environmental issues in Asia. This problem is acute in DHAKA the capital of Bangladesh
and also the hub of commercial activity. The other urban areas
like CHITTAGONG, KHULNA, BOGRA and RAJSHAHI have much lesserhealth problem related
to air pollution. In urban areas sometimes the houses are built on rocks and SOILS, which
radiate radioactive gas from their basement. If this gas is inhaled for a long time it may
cause lung cancer. In the rural areas of Bangladesh, the air pollution problems have not yet
become a point of concern. This is due to fewer motorized vehicles and industries there.
However, brick kilns and cooking stoves are the principal sources of emission in rural
areas. In villages’ wood, COAL, and biomass are used as sources of energy. Thus, it is likely
that in those areas the principal air contaminants are particulate matter and volatile
organic compounds (VOCs).
Basically, there are two major sources of air pollution in Bangladesh industrial emissions
and vehicular emissions. The industrial sources include brick kilns, fertilizer factories,
sugar, paper, jute and textile mills, spinning mills, tanneries, garment, bread and biscuit
factories, chemical and pharmaceutical industries, cement production and processing
factories, metal workshops, wooden dust from saw mills and dusts from ploughed land, and
salt particles from ocean waves near the OFFSHORE ISLANDS and coastal lands. These
sources produce enormous amount of smokes, fumes, gases and dusts, which create the
condition for the formation of fog and smog. Certain industries in Bangladesh, such as
tanneries at Hazaribag in Dhaka City, emit hydrogen supplied, ammonia, chlorine, and
some other odorous chemicals that are poisonous and cause irritation and public
complaints. This may cause headache and other health problems.
With increased rate of urbanization in the country, the number of vehicles is also
increasing rapidly, and contributing to more and more air pollution. The Department of
Environment (DOE), and other related organizations, have identified the two-stroke
engines used in auto rickshaws (baby-taxies), tempos, mini-trucks, and motorcycles as
major polluters. At present, there are about 65,000 baby-taxies among them more than
296,000 motor vehicles ply in Dhaka City alone. Moreover, overloaded, poorly maintained

4. and very old trucks and mini-buses are also plying the city streets emitting smokes and
gases. In fact about 90% of the vehicles that ply Dhaka's streets daily are faulty, and emit
smoke far exceeding the prescribed limit. Diesel vehicles emit black smoke, which contain
unburned fine carbon particles.
The two-stroke engines are now discouraged in Bangladesh because of their pollution
hazard. In view of the serious automobile pollution faced in the metropolis, an initiative
was taken with World Bank support to introduce big buses in the city and discourage the
playing of small automobiles, including baby-taxis. The introduction of air-conditioned city
bus service is an outcome of that initiative.
Sophisticated equipment is now being used to detect air polluters in Bangladesh. As such,
four monitoring stations are set up at four divisional towns, namely, Dhaka, Chittagong,
Khulna, and Bogra. In Dhaka the locations of vehicular emission test are at Tejgaon,
Farmgate, Manik Mia Avenue, Gulshan, Lalmatia, and Agargaon. BANGLADESH
UNIVERSITY OF ENGINEERING AND TECHNOLOGY (BUET) has also been conducting ambient
air quality surveys since 1995.
The air quality standards are different for residential, industrial, commercial, and sensitive
areas. The worst affected areas in Dhaka city include: Hatkhola, Manik Mia Avenue,
Tejgaon, Farmgate, Motijheel, Lalmatia, and Mohakhali. Surveys conducted between
January 1990 and December 1999 showed that the concentration of suspended particles
goes up to as high as 3,000 micrograms per cubic meter (Police Box, Farmgate, December
1999), although the allowable limit is 400 micrograms per cubic meter. The sulphur dioxide
in the air near Farmgate was found to be 385 micrograms per cubic meter, where as the
maximum permissible limit is 100 micrograms per cubic meter. Similarly, in the Tejgaon
Industrial Area the maximum concentration of suspended particles was 1,849 micrograms
per cubic meter (January 1997), as opposed to the allowable limit of 500 micrograms per
cubic meter. Usually the maximum concentration of air pollution in Dhaka is during the
dry months of December to March.
The BANGLADESH ATOMIC ENERGY COMMISSION (BAEC) and the Bangladesh Council of
Scientific and Industrial Research (BCSIR), in collaboration with the DOE, recently
assessedthe concentration of LEAD in the ambient air. The DHAKA SHISHU HOSPITAL in
association with the BAEC also estimated the level of lead in the blood of children of Dhaka
City and the possible impact of leaded gasoline on them. The Bangladesh Road Transport
Authority (BRTA) is also setting up a vehicle emission monitoring station at Mirpur,
Dhaka.

5. Prior to introduction of unleaded gasoline, BAEC reported that the air that city dwellers
breathe on the roads contains lead in concentrations almost ten times above the
government safety standard set by the DOE. The air of Dhaka City holds 463 nanograms
per cubic meter of lead - the highest in the world. From November 96 to March 97 the lead
levels in three different areas of Dhaka City were 123-252 nanograms per cubic meter at
Farmgate area and 61 to 76 nanograms per cubic meter in Tejgaon Industrial area.
Air pollution data from World Health Organization
PM10 158
PM2.5 90
PM10 Pollution Level: Extremely High
The lead poisoning produces neuro-developmental disorders in children. About 50 tons of
lead is emitted in the Dhaka air annually and the emission reaches its highest level in the
dry seasonfrom November to January. Lead poisoning has been detected recently in
children at the Shishu Bikash Kendro (Child Development Centre) of Dhaka Shishu
Hospital. Lead concentrations, measured around 80-micrograms/dl-to180 micrograms/dl in
the testedchildren's blood, is 7-16 times more than the acceptable limit. The safe
concentration advocated by the US Centre for Disease Control and Prevention is 10
micrograms/dl. People living in urban slums have a significant rise in mean blood lead
levels, compared to those living in urban middle-income or rural areas. The development of
lead pollution could also affect the central nervous system, cause renal damage and
hypertension. Excessive leadin the blood of children could damage-their brain and kidney.
Children are three times more at risk than adults are by exposure to lead poisoning.
In Dhaka city the mean blood lead level of rickshaw pullers is 248 micrograms/dl (range
154-344 micrograms/dl), baby-taxi drivers 287 micrograms/dl, traffic police 272
micrograms/dl (range 152-32 micrograms/dl), tempo assistants 255 micrograms/dl, and
petrol pump operators 249 micrograms/dl (range 207-342 micrograms/dl). The mean blood
lead level among these risk groups is found to be higher than the acceptable value, with
traffic police being the worst affected group. The blood lead levels usually increased with
duration of exposure.
During July 1999 the Government of Bangladesh (GOB) executedthe decision to provide
only unleaded gasoline in the country. According to recent measurements between late

6. 1999 and 2000 by BAEC and EASTERN REFINERY LIMITED (ERL) the gasoline dispensed at
pumps in Bangladesh is now totally free of lead.
It has been found that Dhaka city has VOC beyond tolerable limits, some of which
cause CANCER. Emissions from two-stroke auto-rickshaws in Dhaka were found to contain
4 to 7 times the maximum permissible level of VOC.
Dust pollution is causing many RESPIRATORY DISEASES, including ASTHMA. Recently, 200
organic compounds are detected by analysing four air samples collected from the
Shewrapara area of the city. As far as the VOC is concerned the following worst affected
areas are identified: Hatkhola, Manik Mian Avenue, Tejgaon, Farm Gate, Motijheel,
Lalmatia, and the inter-district bus terminals. Surveys conducted between December 1996
and June 1997 showed that the concentration of suspended particles goes up to as high as
2,465' micrograms per cubic metro as against the allowable limit of 400 micrograms per
cubic meter at Farm Gate. In Tejgaon Industrial Area, on the other hand, the maximum
con centration of suspended particles was 630 micrograms as against the allowable limit of
500 micrograms per cubic meter.
Mine air pollution a major issue of concern in Bangladesh. Dust and mine gases create
problems for coalmine. Fortunately BARAPUKURIA COAL of DINAJPUR district has
insignificant gas content, therefore, in the process of mining of coal the danger of methane
emission and methane gas related hazards are considered to be insignificant. As the
Barapukuria coal will be mined mechanically, huge coal dusts would be generated but
proper mitigation measures if taken coal dust could be controlled. Huge dusts will also be
generated in the Maddhyapara HARD ROCK mine in Dinajpur district, due to frequent
movements of heavy vehicles together with required loading and unloading operations. The
gases formed by the combustion of coal, fuel and lubricants in the mine both at the surface
and underground pollute the ambient air. Dusts generated from coal and hard rocks
especially during cutting, blasting, crashing and transportation in the mines are generally
the cause of concern for the miners and for the surrounding localities.
Government decisions recently the Ministry of Energy and Mineral Resources (MEMR)
has taken important decisions, which are as follows (i) the minimum standard of
lubricating oil for two- stroke engine should be APITC or JASOEB and (ii) marketing of
straight mineral oil should stop immediately.
In 1985-86 the BANGLADESH PETROLEUM CORPORATION started a project to
use COMPRESSED NATURAL GAS (CNG) in vehicles instead of gasoline. The primary

7. objective was to reduce vehicular emissions, as combustion of CNG produces less pollution
than gasoline. The World Bank donated Taka 225 million to initiate the project. So far data
on the number of vehicles converted to CNG from 1985 to 1997 are as follows: 1985-86
converted vehicles 2; 1988-89 converted vehicles 19; 1989-90 converted vehicles 9; 1990-91
converted vehicles 6; 1991-92 converted vehicles 10; 1992-93 converted vehicles 16; 1993-94
converted vehicles 3; 1995-96 converted vehicles 13 and 1996-97 converted vehicles 86.
Private sector participation in using CNG for taxicabs is significant. At the beginning of
2002 the Government has started promotional campaign and appropriate push to the
owners of auto rickshaws to use CNG in order to reduce vehicular emissions.
Pollution policy the first regulation related to ENVIRONMENT in Bangladesh was the
Factory Act of 1965, which was followed by the earliest recorded environmental protection
act, known as the 'Water Pollution Control Ordinance, 1970'. However, these ordinances
do not include air pollution problems. Gradually these ordinances were modified and the
Environmental Pollution Control Ordinance (EPC), 1977, was promulgated. It dealt with
pollution of air, SURFACE WATER and GROUNDWATER, and soil by discharge of liquid,
gaseous, solid, radioactive, or other substances. Although the order passedunder the EPC
1977 was legally in place, implementation of environmental laws never took place.
Following rapid industrialization the environmental scenario in Bangladesh changed
dramatically. The Ministry of Environment and Forest and the Department of
Environment were created in 1989 and the Environment Policy of 1992 was introduced.
Further, the Environmental Conservation Act, 1995, and the Environment Conservation
Rules, 1997, were approved by the Bangladesh National Assembly to restrict and mitigate
ever-growing environmental problems in the country.
Bibliography United Nations Environment Programme, State of the Environment:
Bangladesh, United Nations Environment Programme, 2001.

8. Waterpollution
Water Pollution Water is considered polluted when it is altered from the natural state in its
physical condition, and chemical and microbiological composition, so that it becomes
unsuitable or less suitable for any safe and beneficial consumption. The term
contamination is used synonymously with pollution. The signs of water pollution are
obvious: bad taste; offensive odours from lakes, rivers and sea beaches; unchecked growth
of aquatic weeds in water bodies; decrease in number of aquatic animals in surface water
bodies; oil and grease floating on water surfaces; colouration of water; etc. Besides these
obvious signs, there are other kinds of pollution, which are not so visible.
Water pollution
Sources of pollution Factories, power plants and sewage treatment plants are considered
point sources of water pollution, because they emit pollutants at discrete locations, usually
through a pipe that leads to a lake or STREAM. Nonpoint sources of water pollution are
scattered or diffused. Cropland, FORESTS, urban and suburban lands, roadways, and
parking lots are nonpoint sources of a variety of substances including dust,
sediment, PESTICIDES, asbestos, FERTILIZER, heavy metals, salts, oil, grease, litter, and even
air pollutants washed down from the cloud by rain.
Water pollution can also be categorized into natural and anthropogenic sources. Natural
sources are those which take place without human influence. Anthropogenic pollution are
those which are induced by human beings. Natural pollution can also be accentuated by
human activities.

9. Pollution takes place in all the three main sources of water, ie rain water, SURFACE
WATER and GROUNDWATER. Surface water is more susceptible than groundwater, which is
naturally protected from surface activities.
Rainwater pollution Acid rain damages forests and may cause significant decrease in
productivity. Numerous authors have also raised concern for crop damage. Acid rain is
particularly damaging to buds; therefore, acids falling on plants in springtime may impair
growth. Acidification of SOIL may also impair soil bacteria that play an important role in
nutrient cycling and nitrogen fixation. Acid rain is also capable of corroding manmade
structures. Examples of such corrosion are: the Statue of Liberty, the Canadian Parliament
in Ottawa and Egypt's temple at Karnack. Acid rain may also damage house paint and
etch the surfaces of automobiles. There is no record of acid rain in Bangladesh. However,
due to extensive AIR POLLUTION in Dhaka city, it is very likely that rain water in Dhaka
would be more acidic than rain water in rural areas.
Surface water pollution Surface water occurs in OCEANS, rivers, lakes, ponds and
floodplains. It has been the source of water supply since the dawn of civilization. But
intense human activities have been polluting these readily available sources. Surface water
used to be the primary source of water supply in Bangladesh, but it is no longer the case.
Surface water in Bangladesh is extensively polluted by sources such as industrial and
urban wastes, agrochemicals and sewerage wastes and seawater intrusion. Surface water
bodies are extensively used for disposal of untreated industrial wastes and this is one of the
main sources of pollution. The BURIGANGA is a typical example of serious surface water
contamination. Apart from industrial sources, surface water in the country is also
extensively contaminated by human faces as SANITATION in general is poor. Agrochemicals
are extensively used in the country causing pollution of surface water. Due to withdrawal of
water from the Ganges, seawater intrudes a long way inside the coastline which causes
river water pollution by salinity. There are also other minor sources that contaminate
surface water extensively.
Groundwater pollution Although groundwater is not directly exposedto surface polluting
activities, numerous natural and anthropogenic activities cause groundwater pollution. A
number of physical, chemical and biochemical (and microbiological) processes cause
alteration of groundwater properties either by addition of new elements/ions/compounds or
by increasing the existing concentrations. Before the discovery of arsenic contamination in
Bangladesh, groundwater used to be considered a safer source of drinking water. Arsenic
contamination of groundwater in Bangladesh is now considered the world's largest case of

10. water pollution. Groundwater in Bangladesh is also polluted by a number of anthropogenic
and natural sources. The most widespread anthropogenic sources are the infiltration of
industrial and urban wastes disposed on the ground or in surface water bodies. Also
intrusion or infiltration of saline water contaminates groundwater. Extensive use of
agrochemicals can lead to groundwater pollution. Leaking sewers/septic tanks/pit latrines
also cause groundwater pollution.
Effects of water pollution:
1. The dissolved oxygen level of many of the rivers’ water has reached at lethal level.
2. Due to over spilling of pollutants during the rainy season, the agricultural lands are
contaminated that they have lost their crop growing capacity and hence remain unused all
the year round.
3. Sometimes the pollutants enter food chain eventually killing birds, fish, and mammals.
4. The scientists in a recent research on the Karnaphuli found traces of radioactivity ‘very
close to risk level’ on the soil. If radioactivity of the river soil goes up it will hamper the
natural breeding of fish as well as growth of fishes. If the people eat the affected fish it may
spread to their body.
According to the United Nations Scientific Committee on the Effects of Atomic Radiation
on 2000 (UNSCER), normal level of radiation hazard due to radioactivity is 0.5. The
scientists in their research got 0.6507 for external radiation hazard and 0.82 for internal
radiation hazard where the risk level is 1.
5. Pollution is so acute that hardly any hydro-organisms can tolerate it and eventually, fish
of many species are found floating dead in the river water. These dead fishes gradually get
rotten and highly add to the further pollution of the river water.
6. Due to rotting jute in the river (Chitra) water the water quality of the river is in an
inferior position as aquatic creatures are dying for lack of oxygen.
7. The river pollution has also hit the local fishermen hard. Life has become difficult for
them as they lost their income source.
8. This also results in the alteration of geomorphic features which can then change in the
geometry and sedimentary characteristics of river channels, flood plains and deltas.
9. Industrial pollutants such as lead, cadmium, iron, copper and organic wastes from
leaking sewage systems can accumulate in rivers. Referred as bioaccumulation, this process
can ruthlessly affect water quality and species survival. More importantly,
bioaccumulation of metals in fish, crabs and other edible aquatic species, may cause health
problems to enter the food chain. Also, this can destroy the water aeration system, the self-
purifying process of rivers.

11. 10. Eutrophication, a process of absorbing excessive nutrients (especially N and P) beyond
their buffering capacity of water bodies leads to the loss of species diversity through
increased species mortality, changes in species collection and loss of aquatic flora and fauna
diversity.
Pollution in Dhaka, Bangladesh
Air Pollution 85.00 Very High
Drinking Water Pollution and Inaccessibility 66.67 High
Dissatisfaction with Garbage Disposal 82.50 Very High
Dirty and Untidy 83.33 Very High
Noise and Light Pollution 75.83 High
Water Pollution 81.90 Very High
Dissatisfaction to Spend Time in the City 83.87 Very High
Dissatisfaction with Green and Parks in the City 85.34 Very High
Purity and Cleanliness in Dhaka, Bangladesh
Air quality 15.00 Very Low
Drinking Water Quality and Accessibility 33.33 Low
Garbage Disposal Satisfaction 17.50 Very Low
Clean and Tidy 16.67 Very Low
Quiet and No Problem with Night Lights 24.17 Low
Water Quality 18.10 Very Low
Comfortable to Spend Time in the City 16.13 Very Low

12. Quality of Green and Parks 14.66 Very Low
Some steps to minimize pollution in last few years:
There is always a try to minimize pollution. Tongi Industrial Area have unanimously
decided for establishing and operating a central ETP with their concerted effort with a
view to tackling the Turag River pollution (Prothom-Alo, August 31, 2010). Some projects
are initiated to lessenthis huge pollution by the government though these all are not
effective always.
The government has taken a decision to shift the tannery industry from Hazaribagh to
Saver. The water board designed sluice gates on the Jamuna near the Bangabandhu
Jamuna Bridge from where the waters would be diverted to the Buriganga.
To save the river from the encroachers and pollution as well as their existence, the sampan
majhis organized a three-day sampan khela (boat race) and Chantgaiya (Chittagong)
cultural fair in the river Karnaphuli. Sampan Majhi Kalyan Samity Federation (SMKSF)
in association with Chattagram Anchalik Sanskriti Academy (CASA) organized the events
titled “We are boatmen of the river Karnaphuli and we have pledged to save the river”.
References:
http://en.banglapedia.org/index.php?title=Air_Pollution
http://www.bangladeshenvironment.com/index.php/polution-s/air-polution/291-air-
pollution-in-dhaka-city
http://www.buet.ac.bd/me/icme/icme2009/Proceedings/PDF/ICME09-RT-19.pdf
http://www.numbeo.com/pollution/city_result.jsp?country=Bangladesh&city=Dhaka
http://en.banglapedia.org/index.php?title=Water_Pollution
http://fairbd.net/water-pollution-of-most-of-the-water-sources-in-bangladesh/