The increase in the number of motor vehicles, industrial and commercial activities, coupled with the rise in construction work in and around the city, is translating into a lot of air and noise pollution for the residents.

Almost every part of the city suffers on account of air and noise pollution, much of it caused by automobiles. The city’s ambient air quality on several parameters leaves much to be desired, with the levels of pollution above the permissible limits.

Several monitoring bodies, engineering institutes and medical colleges are constantly evaluating measures to reduce the pollution levels. Though some initiatives have paid off, much more needs to be done if the ambient air quality can be described as healthy.

According to the Tamil Nadu Pollution Control Board (TNPCB) statistics for the six-year period ending 2006, though the levels of sulphur dioxide and nitrogen dioxide were low, the level of suspended particulate matter (SPM) was much higher than the permissible limit. Road dust kicked up by the near-constant vehicles movement also contributes to high levels of air pollution in several areas, including Vallalar Nagar, T. Nagar and Kilpauk. The growth of the construction activity and the associated movement of material-laden heavy vehicles, especially through residential areas, such as Anna Nagar, compound the problem.

On pollution counts too, north Chennai is worse compared to the rest of the city. At a medical camp in north Chennai recently, doctors found that tuberculosis of organs other than the chest was a common disease. North Chennai Indian Medical Association vice-president S. Jayachandran said 30 per cent of his patients from the localities, mostly labourers, suffer from a range of problems, including respiratory disorders, asthmatic bronchitis, allergic rhinitis, sinusitis, knee-joint and low-back pain. They were caused by environmental factors and occupational hazards, he said.

Royapuram Residents Welfare Association vice-president E. Earnest Paul complained of pollution caused by coal and iron-ore dust in the area. “Noise pollution by heavy vehicles and container trailers is another perennial problem,” he said.

While air pollution remains a silent killer, the impact of noise pollution is much more apparent and fast. “Proximity to the noise could have an impact on the hearing capabilities of a person,” according to ENT specialist Ravi Ramalingam. “Constant exposure to noise results in a temporary threshold shift and weakens the hearing nerve. The human ear can hear sounds ranging from 20 to 20,000 hertz. We usually get patients who cannot hear sounds above 6,000 hertz,” he explained. “Once you have lost the hearing ability, you cannot get it back. You lose both volume and clarity. Hearing aids can give only clarity not volume.”’

Though all environmental standards are health-based, mitigation of pollution problems has been historically viewed from a purely engineering perspective, according to Kalpana Balakrishnan, Head, Department of Environmental Health Engineering of Sri Ramachandra University. She called for sophisticated testing equipment to understand the city’s major environmental health concerns. “Health impact assessments to assess the public health implications are rare as resources (both infrastructural and human) for environmental epidemiological investigations are scarce,” she said.

“We need considerable inter-disciplinary skills. It is important to set realistic targets so that whatever is currently feasible is implemented effectively in the near term,” said Dr. Kalpana, who is also the director of WHO-Collaborating Centre for Occupational Health.

The Centre has data on sector-wise occupational health profile of workforce in many industry clusters in and around Chennai. Acute effects of air pollution on mortality similar to what has been observed in many other countries have also been documented.