The New Nation - Internet Edition

Manir Hossain

Water is the most vital element among the natural resources, and is crucial for the survival of all living organisms. The environment, economic growth and development of Bangladesh are all highly influenced by water - its regional and seasonal availability, and the quality of surface and groundwater. Spatial and seasonal availability of surface and groundwater is highly responsive too the monsoon climate and physiography of the country. Availability also depends on upstream withdrawal for consumptive and non consumptive uses. Bangladesh is the lower riparian of three major river systems, the Ganges-Padma, the Brahmaputra-Jamuna and the Meghna (GBM). The problem is that we have to much water in the monsoons and too little in the dry season. Water resources are being degraded by untreated domestic and raw sewage, untreated industrial effluents and municipal wastewater, runoff pollution from chemical fertilisers and pesticides from agricultural practices and other sources, and oil and lube spillage in the coastal area from the operation of sea and river ports. Construction of flood-control embankments and roads are impending water flows and both the wetlands and their fishery resources are under threat.

Erosion from deforestated areas, degradation of watersheds and poorly managed agricultural land have reduced dry seasons river flows, exacerbated flooding in wet seasons and diminished ground-water recharge. Scarcity of water in the dry season are caused for following reasons- · Upstream withdrawal for consumptive and non-consumptive use · Low rainfall · Gradual siltation in river bed and floodplain · Dry season irrigation. The crisis that we are witnessing today, whether of scarcity and pollution of water and associated phenomenon with water are the degradation of soil, devastation of forests and the rapid diminution of bio-diversity, is essentially a crisis of the human spirit. Thus for the survival of all living components including human being in a better environment, water resources need to be managed and we have take effective steps to combat water crisis and pollution. The task would become easier if the government agencies fulfilled their own environmental duties and responsibilities effectively and the role of civil society by their meaningful participation in environmental issues, and help in tackling the problems, through public -interest litigation. So, come on, to ensure green planet for the present people and for the future generation by taking all possible steps for stopping the crisis and pollution of water.

Air is a life sustaining precious natural resource. Air is called the life. Fresh air is one of the most indispensable gifts of nature without which humankind will not survive. And human activities can be interfered by the pollution of this vital resource.

According to U.S. Public Health Service, " Air pollution may be defined as the presence in the indoor atmosphere of one or more contaminants or combination thereof in such quantities and of such duration as may be, or may tend to be injurious to human, plant or animal life, or property, or which unreasonably interfere with the comfortable enjoyment of life, or property, or the conduct of business". The air is composed of 78% nitrogen, 21% oxygen and 0.9% argon, with trace amounts of other gases, liquid droplets and solids. This composition is almost constant up to 100 km height. For active gases and aerosols, there are important variations seasonally, geographically and vertically. The impact of the composition of air on mankind is limited to possible changes in the concentration of the trace gases, like Carbon dioxide (CO2), Total Ozone (O3), Sulphur dioxide (SO2), Methane (CH4), Nitrogen dioxide (NO2) and liquid and solid aerosols. The air pollution occurred due to the addition of air pollutants in the atmosphere.

The pollutants may introduced into the atmosphere through following ways-

i. Emitting gases and particulates, particularly from fossil fuel combustion, domestic and industrial sources and transports;

ii. Burning stable, forest and grassland fires;

iii. Ploughing, overgrazing and other human activities releasing dusts that rise in dry windy weather and augment, and are naturally present in the atmosphere;

iv. Releasing particulates that act as condensation and freesing nuclei;

v. Automobile exhausts, jet engine emissions and combustion of wood and refuse;

vi. Different industrial activities such as oil refinery,

petroleum, power plants, fertilizer, tanning industry and sewage treatment plants, cement and glass industry; and

vii. Photochemical reactions in atmosphere and reactions induced by silent electrical discharge and intense u.v. radiations in the atmosphere.

Air pollution badly affects the respiratory tract, cause irritation, headache, fatigue, asthma, high blood pressure and even cancer. The effects of air pollution are as follows- Increased breathing rate and feeling of air-starvation; Suffocation, aggravation of asthma and chronic bronchitis and blood poisoning; Impairment of pulmonary functions and lung defences; Respiratory irritation, sensory irritation and irritation of throat and eyes; Poisoning cell enzymes and damaging nerve tissues; Corrosion of mucous membranes and teeth; Toxicity from metallic dusts, silicosis and asbestosis from the specific dusts; and Formation of carboxy heamoglobin, which is useless for respiratory purposes and hence leads to death.

To protect human health from air pollution hazards we have to take some effective measures immediately. The control of air pollution can be achieved through following two basic ways-

Controlling or confining the pollutants at source which can be achieved by- a) modifying he process in such a way that pollutants do not form at all beyond permissible concentrations and b) reducing the pollutant concentration to tolerable level before they released to the environment, by use of suitable equipment to destroy, alter or trap the pollutants formed.Dilution of the pollutants in the atmosphere to permissible levels before they can reach the receptor which can be achieved by using tall stacks, controlling the process parameters, with due regard to the local meteorogical conditions and proper community planning to prevent accumulation of dangerous ground level concentrations within the designated areas.

Thus for the better environment we should take all possible steps to control or reduce air pollution. Fresh air is very necessary for human life. So, we must ensure fresh environment for the present generation as well as for the future generation by protecting, controlling or reducing air pollution.

Soil Pollution: Soil pollution is defined as the buildup of persistent toxic compounds, chemicals, salts, radioactive materials, or other disease causing agents in soils which have adverse effects on plant growth and animal health. The soil is composed of both organic and inorganic components. The organic components of soil includes-remains of plant roots, earth warms, mites, millipedes, centipedes, grubs, termites, lice, springtails, bacteria and fungi etc.

The inorganic matter of soil includes- sand, silt, clay, potassium, calcium, magnesium, phosphorus, sulfur, iron, manganese etc.

The soil pollution may occurs due to following activities-

Agricultural activities where chemical fertilisers and pesticides are used;

ii. Industrial activities; iii. Mining activities; iv. Erosional and weathering activities;

v.. Nuclear power plants and radioactive waste disposal activities;

vi. Improper irrigation practices; vii. Direct discharge of different toxic and hazardous industrial and chemical waste into the soil.

Many effects may occur due to soil pollution. Human health is adversely affected by the pollution of soil. Some soil pollutants can cause carcinogenic effects and others may destroy the brain, nervous system, kidney function and so many health problems such as headache, fatigue, eye-irritation, skin diseases etc. The effects due to soil pollution are- Disruption of soil ecosystem as well as the whole earth ecosystem; May cause decreasing of soil microbes; Alteration of metabolic activities of plants;

Sometimes soil pollution may cause eutrophication; May decrease the soil fertility and many other problems.

The soil pollution is increasing day by day. So we must control or prevent such kind of problem for our safe environment by taking all possible steps immediately.

The systems that can be adopted for the controlling of soil pollution are as follows- Proper treatment of solid and liquid industrial wastes;Proper control and management of agricultural wastes;Proper dumping and treatment system may be applied for controlling of municipal and domestic wastes;Control of over population growth;Deforestation should be stooped;Avoiding or/and restricting the use of highly toxic and persistence chemicals;

Imparting of formal and informal public awareness programs and encouraging the use of bio-pesticides.

Thus for the safer and better environment for the present as well as for the future generation we must control or stop soil pollution.

Noise Pollution: We the man creates sound for our communication and other purposes. A sound may be music to one person but noise to another; acceptable when soft, rhythmic or for short time, but unacceptable when loud, random or prolonged. The noise is a by-product of human activity and the background noise levels have been found to be increasing year by year for the last few decades. Thus noise pollution is defined as an exposure of people or animals or any other living matter to the levels of sound that are annoying, stressful, or damaging to the human ears. The soureces from which noise pollution may occurs are as follows- Automobiles; Industrial units;

Low-lying aircraft; Loud speaker; Construction equipments; Machineries;

Shooting of guns; Fine cracker; and Home activities and so many other sources.

The noise pollution is major health hazard in the country, particularly in urban areas. The ill effects and health hazards due to noise pollution includes- i. Hearing loss; ii. Physiological effects; iii. Speech interference;

iv. Behavioral effects; v. Annoyance; vi. Effects on efficiency; vii. Fatigue;

viii. Mental health effects; ix. High blood pressure; and so many other health and other problems such as effects on respiratory system, dizziness, loss of physical control, vomiting etc.

The following approaches may be adopted for the control or reduce noise pollution- a. Suppression of the noise at the sources; b. Modifying some of the present practices and procedures in order to minimize the noise; c. Shielding the sources of noise generation; d. Shielding the noise receiver; e. Shifting noise sources and things away from the people; f.

The control of noise in the transmission or propagation steps through some mechanisms such as sound absorption, sound insulation and vibration control etc. It is true that noise pollution is a health hazard, but nothing has done so far to reduce the noise pollution. The authority concerned must create awareness among the people so far that in the long run we can eradicate sound or noise pollution from our society once for all.

For our better survival as well as for other living beings existence, we must protect all types of environmental pollution.

(Manir Hossain is a president of Society for Environment and Nature Study (SENS) at Mawlana Bhashani Science and Technology University, Tangail. E-mail: Manir_nir @yahoo.com )

Shilpi Rani Roy

Joinal Miah, in his mid-50s, enjoyed a good health until he was a farmer. Things have changed fast when he started working in a brick kiln. Now he is undergoing treatment at a city hospital.

"Doctors say he is suffering from by asthma," says Joinal's wife Rahima.

The smoke caused by low-quality coal used in brick-kilns contains poisonous sulpherdi-oxide, different oxides of carbon and nitrogen, iron and lead. This contaminated smoke is making the city's air even more polluted, causing various diseases, including asthma, to the city dwellers.

According to researches and surveys conducted by the World Bank and Unicef, environmental pollution, particularly air pollution, is responsible for 30 serious diseases.

With the increase in its population, a city needs infrastructures to accommodate these additional people. Although Bangladesh is still a poor country, there has been a significant change in its people's socio-economic life. So, brick buildings and concrete roads are being constructed instead of traditional houses made with CI sheets and woods.

The rate of constructing buildings with bricks and concrete roads in the sprawling city of Dhaka is higher than any other places in the country due to rapid increase in its population. Brick is widely used in constructing buildings and roads due to scarcity of stones. This is perhaps the reason why there are too many brick-kilns around the capital.

If one enters Dhaka city through any of the points like Aminbazar, Keraniganj, Fatullah, Pagla, Tongi and Ashulia, he or she will inevitably see so many bazaars, columns of chimneys and smokes.

Statistics show that there are more than 3000 brick-kilns across the country of which 522 are situated around capital Dhaka. Most of them have been set up alongside rivers, canals and roads. According to an estimate, about 80 crore bricks' are produced in these brickfields every year.

"Like Dhaka, there is no city in the world that is surrounded by so many brick-kilns," says Prof AQM Mahbub, a teacher of Geography and Environment Science at Dhaka University.

He says, "Taking the environmental pollution into consideration, the use of woods was completely banned. But, this rule is hardly practiced. Not only wood, low quality coal and even plastic, rubber and tires are used in the brick-kilns and emitting poisonous black smoke, polluting the air of Dhaka, a city of 15 million people. Dhaka is the worst for living among South Asian cities."

According to the Ministry of Forest and Environment, the air pollution in Dhaka has not improved that much despite banning of two-stroke auto-rickshaws and tempos, and the blame goes to the brick-kilns.

Kamal Hossain, a brickfie1d owner, said 400 to 1,200 metric tons of coal is burnt every season in one brick-kiln. Besides, at the beginning of the season, every kiln requires 7,500 to 30,000 kilograms of firewood to light up the coal.

Environmentalists say the brick-kilns release hundreds of tons of smoke, dust and carbon. These injurious elements do not confine to the air of adjacent areas of the brickfields, but also travel to other areas, affecting a large section of people.

Humayun Kabir, an associate professor of Geography and Environment Science at the Dhaka University, says the remains of materials burnt in the kilns are increasing the acidity of soil. As a result, the fertility is decreasing. The growth of trees and fisheries are also being affected by the brick-kilns.

He further says the amount of arable land is reducing because of the use of soil in the brickfields. Besides, the cropland adjacent to the brick -kilns is getting unsuitable.

Under section 5 of the brick burning-related law enacted in 1989, the use of firewood is banned. This law was amended twice in 1999 and 2001. Despite including new provisions, the trend of setting up of brickfie1ds violating rules has not stopped.

The provision of using 120-feet chimney is also violated. The amended law says no license should be issued for setting up a brickfield within three kilometers of residential area and fruit gardens. If any license was issued earlier before the amendment allowing setting up of a brickfie1d within the prescribed distance, the concerned license holder will remove it to a suitable location, or else, the license will be cancelled. But no one cares about it.

Badrun Laila, an officer at the Disaster Research Training and Management Centre, says, "With the expansion of Dhaka city's periphery, the number of brickfields is going up in an unplanned manner. Brickfie1ds badly affect trees and fertility of land in the localities. The air of brickfield-surrounded Dhaka is worst in South Asia."

Making some recommendations for averting any environment disaster, environmentalist Prof Nazrul Islam says the use of 120-feet chimney stipulated by the government will have to be ensured so that the smoke cannot go downward. The pollution will go down if the use of gas in brickfields can be increased. Besides, the government can fix certain areas for setting up brick-kilns.

Prof Mahbub emphasises the use of solid concrete and ceramic bricks as an alternative to conventional ones. He also stresses the need for using good quality coal and special chimneys that can filter carbon from the smoke.

- NewsNetwork