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Dust hazards, especially in urban areas is endangering public health by affecting human respiratory system, damaging vital organs like lung and obstructing normal breathing, reports BSS.
Millions of people are exposed to dust in the country for at least five months in a year from November to March when rainfall is very little.
Director of International Training Network (ITN) and Professor of Bangladesh University of Engineering and Technology (BUET) Mujibur Rahman told the news agency dust hazard can be controlled if its sources are identified.
Dust carries physical, chemical and biological particles like carbon, sulpher dioxide, nitrous oxide and viruses harmful to health, he said and added people suffering from chronic asthma, children and aged people are also vulnerable to dust.
Rahman, an environmentalist, said dust also causes nose and throat irritation and bronchitis while toxic particles like lead, cadmium and dioxins cause cancer and reproductive problems.
He said open-air construction practices, open trucks carrying dusty construction materials like cement, sand and soil, crushing of bricks and stones in open space, road cutting and dumping of soil on the streets, faulty system of solid waste collection, absence of effective road sweeping and vehicular, industrial and brick field emissions are the main sources of dust in urban areas, he added.
He said although there is no detailed studies on urban dust situation in the country, it is assumed that at least 20 to 30 per cent of dust is produced from construction activities.
About 270 micrograms of suspended particulate matters have been found in one cubic meter of air in Dhaka in the month of January 2003, a study said and added normal presence should be within 150 micrograms.
Sediments in rivers from upstream, river erosion, siltation, deforestation, hill cutting, coastal salt fields and heavy rainfalls produce huge amount of dusts in the rural environment, it added.
The study said with the economic development in Bangladesh migrations from rural to urban areas have been increasing, the study said and added at least 24 per cent of the people are now living in the urban areas that contribute 75 per cent of the GDP and they are exposed to dust hazards and need immediate protection.
Spraying water on the street is a traditional practice of dust control, Rahman said and added to improve dust control system in urban areas, construction sites should be surrounded by CI sheets or other protective fences.
Construction materials should be covered properly by thick polythene or jute sheets while brick and stone crushing should be done outside the city in covered sheds treating it as an industrial activity, he added.
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