Thermal power stations, industries, vehicles and non-commercial fuels like coal briquettes, animal dung and trash are causing air pollution.Water is contaminated by municipal and industrial waste, chemical fertilisers, pesticides and silt from degraded catchments.

Animal overgrazing, deforestation, improper irrigation practices, poor land use practices, intensive agriculture and over-cultivation and garbage dumping are degrading the soil.

Industry contributes to the degradation of air, water and soil. Pollution is unevenly caused by different industrial sub-sectors, though. Says Dilip K Biswas, chairperson, Central Pollution Control Board (CPCB), ``Pollution caused by various sub-sectors of industry is disproportionate to their contribution to the total industrial output.''

Headds that the CPCB has identified 17 categories of significantly polluting industries in terms of both air and water pollution. The list includes iron and steel, thermal plants, copper/zinc/aluminium smelters, cement, oil refineries, petrochemicals, pesticides and fertiliser units. In a survey of 1,551 units from these 17 categories, CPCB has found that only 1,264 have installed adequate pollution control facilities.

The processing of industrial chemicals generates 40-45 per cent of the total pollution load generated by industry. Another 40 per cent in terms of BOD (biochemical oxygen demand) comes from food industries. Industrial chemicals and the paper and pulp industries are other significant contributors, according to Green India 2000, published by TERI.

Among the organic industries, agro-based industries generate 65-70 per cent of the total industrial organic waste-water. Most of the organic pollution is generated by the fermentation industry, and the paper and pulp industry. Besides, agro-basedindustries like dairies, edible oils, vanaspati industries, flour mills, food processing units, fermentation industries, starch industries and sugar mills also generate organic waste-water.

Notes Rajendra K Pachauri, director with TERI, ``While larger industries are adopting pollution control measures, small scale industries are not.''Explaining the reason, S P Chandak, director with the National Cleaner Production Centre, adds, ``Small scale units are not equipped financially and technically to take pollution control measures.'' And small scale units number over three million and account for nearly 50 per cent of the total industrial production and 60 per cent of the industrial pollution, he adds.

Major air polluting small scale industries include foundries, chemical manufacturing and brick making units.

Evaluating environmental degradation is tricky, but the World Bank has nevertheless estimated it to be $9.7 billion a year, or 4.5 per cent of GDP (1992 values) in terms of health and productivityimpacts in its The Cost of Inaction: Valuing the Economy-Wide Cost of Environmental Degradation in India.

This includes health impacts of water pollution ($5,710 million), agricultural output loss due to soil degradation ($1,942 million), health impacts of air pollution ($1,310 million), loss of livestock carrying capacity due to rangeland degradation ($328 million), cost of deforestation ($214 million) and loss of international tourism ($213 million). Degradation due to water pollution (production impacts), industrial hazardous waste, coastal and marine resources, and loss of biodiversity have not been estimated since these are difficult to compute as of now.

The back-of-the-envelope figures are not only rough estimates, but also on the lower side, admits the World Bank report. Even so, these are enough to offset the annual growth estimated through traditional methods. And the costs are set to only increase at our own peril if the environmental degradation is not reversed.