A study by the Centre for Science and Environment (CSE), using air pollution data for 1995 provided by the Central Pollution Control Board (CPCB), estimates that a stupendous 51,779 people are dying prematurely every year in 36 Indian cities.

In 1991-92, the estimate of air pollution related deaths was 40,351, according to a World Bank (WB) report published in 1995, Valuing Environmental Costs in India: The Economy-wide Impact of Environmental Degradation. This represents an increase of 28 per cent in a three-four year period, says CSE director Anil Agarwal. During this period, the number of annual air pollution-related deaths doubled in Calcutta, Kanpur and Hyderabad, while in Delhi the figure rose from 7,491 to 9,859 -- an increase of almost 32 per cent. The number of hospital admissions and illnesses requiring medical treatment in the 36 cities is estimated to be 25 million. The World Bank (WB) estimate for 1991-92 is 19 million.

The main culprit is suspended particulate matter (SPM) -- dust and ash particles that are often laden with toxic chemicals. The primary sources of SPM are auto emissions, industrial units and power plants. SPM levels in Delhi, Kanpur, Mumbai, Calcutta, among others, are three to five times higher than the annual average acceptable limit set by the World Health Organization. Dust particles less than 10 and 2.5 micron in diameter -- PM10 and PM2.5 -- can penetrate lungs easily. PM10 has been associated with premature mortality through respiratory illnesses and cardiovascular diseases, as well as increased morbidity because of chronic obstructive lung diseases.

The CSE study estimates that premature deaths because of growing levels of SPM result in annual economic and health costs of approximately Rs 4,500 crore. The WB estimate for 1991-92 is Rs 3,507 crore. Monetary losses due to sicknesses caused by high levels of SPM are estimated to be approximately Rs 160 crore.

The CPCB report, however, states that SPM levels in some cities such as Pune, Bhopal and Agra, were lower in 1995 than in 1991-92. But does this mean that there is a corresponding decrease in air pollution-related deaths and illnesses? CSE and Down To Earth staffers who visited the three cities found -- after speaking to residents, doctors and experts -- that this may not be the case. On the contrary, health problems due to air pollution may be on the rise in these cities.

Despite scientific evidence and the indicative trend of increasing number of deaths and illnesses due to small particulate emission levels, no attention has been paid by the Indian air quality planners to generate data on the levels of PM10 and PM2.5 in the ambient air. However, a study on the air quality of Mumbai carried out by WB in 1992-93, and published in 1996, provides field evidence to support the approximation that about half of the total SPM comprises PM10. It also makes the dramatic revelation that about 40 per cent of the PM10 comes from the transport sector. As vehicles in Delhi account for about 65 per cent of the total air pollution, compared to 52 per cent in Mumbai, it may be reasonable to conclude that emissions from vehicles account for more than 40 per cent of the total PM10 load in Delhi.

The situation is likely to worsen with the number of diesel vehicles increasing every day. In Delhi, the number of diesel vehicles have increased from 1,08,778 in 1991 to 1,68,000 in 1996 and, in Bhopal, the number of vehicles running on diesel in 1997 is approximately 1,13,000. This is likely to increase further as fuel is heavily subsidised by the government. This is alarming because, diesel vehicles produce higher levels of small particulate matter than other vehicles.

Besides, the government has been unable to reduce the high sulphur content in diesel, which is a major factor behind the high levels of particulate emissions. In India, the sulphur content in diesel is to be brought down from its present level of 1 per cent to 0.25 per cent by the year 2000. In the countries of western Europe, on the other hand, the maximum permissible sulphur content is 0.05 per cent. This assumes significance also because diesel generators are used in a large scale.

As if all this were not enough to kill people, 90 per cent of petrol and diesel dealers in Bhopal sell adulterated fuel. This also contributes greatly to high emission levels. Huge quantities of kerosene are often mixed in petrol, as the latter is about seven times more expensive.

The situation is serious. People are dying a slow death and shall continue to do so in greater numbers unless the government and interest groups such as industry, especially the automobile industry, begin to clean up their act immediately, says Agarwal. The concerns raised one year ago by CSE were ignored. For the sake of our health, and that of our children, we hope that the issue is not brushed aside this time. The slow murder must stop.