Sound pollution: Silent killer
by Syeda Nazia Afrin and Alpha Arzu
At 10, Sujan began working at a welding factory, where pieces of metal are joined together by hammering and using electricity-generated flame. Welding work produces a lot of noises - sometimes deafening.
Four years later Sujan was sitting outside the Ear, Nose and Throat or ENT section of Dhaka Medical College Hospital. He was among dozens of men, women and children awaiting treatment, mostly for hearing difficulties.
Sujan found it difficult to answer questions from these reporters. That was because he had been afflicted with deafness.
"Sujan can’t hear what you say. He was not a born deaf. We sent him to work at a welding factory four years ago. It was all right even two years after he began working there. We now find him afflicted with deafness," said Sujan’s mother, who brought her son to the hospital.
Was it because the teenage boy was exposed to high level of sound at the welding factory? "The doctors can say better," said the middle-aged woman.
But Dr. Shabnam at the Dhaka Medical College Hospital has an answer. "The sound pollution is a silent killer," said Shabnam, "Many of those who come to us with hearing complaints do not know that sound pollution is the culprit." The case of Sujan is an example, she said. The boy has gradually lost his hearing ability not really knowing it well.
Raziur Rahman is a 27-year-old staff reporter at an English daily in Dhaka. He said the city’s sound pollution has made him mentally ill. "I feel uneasy whenever I go out on the streets, where traffic explodes into din. The loud traffic noises cause my head spinning; blood pressure rises. So is the body temperature," said the young reporter. The illness related to sound pollution leads to appetite loss and disturbs sleep, he said.
Several hospital doctors said they treat many patients who come to them with complaints such as high blood pressure, insomnia, headache, appetite loss and palpitation.
Dr. Mohammad Ahsanullah, a medical officer at the ENT department of the Dhaka Medical College and Hospital said, "An average of three patients come to me a day with complaints of hearing difficulties caused by sound pollution. Besides, there are cases of people becoming deaf due to bomb blasts."
Sound pollution -related deafness is the prime illness caused by the environmental hazard, he said adding, "it happens so slowly that many patients can’t detect it until it deteriorates." Many of the patients, he said, are those who work at welding machines or factories, where loud sound is the norm of the work.
"We are able to diagnose it by learning the patient’s history of illness," he said.
The streets of Dhaka city are notorious for alarming sound, much of it caused by unchecked honking. Dhaka’s traffic is chaotic too.
According to Dhaka City Corporation, the city has 2240 kilometres of streets, where there are more than 300,000 rickshaws; 35,000 auto-rickshaws or baby taxies; 15,000 tempos; 100,000 cars and 11,000 buses and trucks. In addition, there are several thousand motorcycles.
Environment authorities said while cars produce up to 90 decibel of sound, it is 118 decibel for motorcycles. Buses and trucks are responsible for producing up to 95 decibel of sound.
Dhaka’s motorised traffic, however, produces higher sound because many of the vehicles are reportedly unfit.
However, sound up to 60 decibel is good for human beings, according to World Health Organisation. But Dhaka has an average of 110 decibel sound pollution generated by its noisy traffic.
The Directorate of Environment has recently conducted a survey on sound pollution on Dhaka streets. It found that the average sound pollution outside Shahin School and College is 74 decibel; at Motijheel Government School 79 decibel during day time. Worse still is that the sound pollution is up to highest 82 decibel and the lowest 54 decibel.
"Consistent exposure to sound pollution causes hearing difficulties. It is also responsible for headache, high blood pressure, breathing difficulties, hormone and digestive problems. It also affects memory of a person and leads to mental problems," said Dr. Soheli Chowdhury, a medical officer at the ENT department of Dhaka Medical College and Hospital.
Syeda Rezwana Hasan, Director at Bangladesh Environment Lawyers Association or BELA said the use of hydraulic horns by a section of buses is one of the main sources of sound pollution. She urged police to regularly check the vehicles to stop using the hydraulic horns. Baby taxies, she said, are also another sources of sound pollution.
Generators used by the garment factories in residential areas are also causing sound pollution, she said.
A number of decisions have been made to try to prevent sound pollution. In addition, the High Court in a recent ruling asked the authorities to make sure that vehicles don’t use the hydraulic horns.
Doctors for Health and Environment have also recommended a number of steps to the government to end the menace of sound pollution.
The suggestions include: a. use of silencer at sound-producing factories; b. ban use of loud horns by vehicles; c. proper implementation of law in this regard.
"Let’s us act together to kill the silent killer - the sound pollution," said Dr. Golam Sarwar of Doctors for Health and Environment. –NewsNetwork
Source: The Daily Independent, Dhaka, December 31, 2001