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The development of the catalytic converter was society's response to smog problems. The installation of this clever device in the exhaust system has been mandatory on all new cars sold in the United States since 1975. It accomplishes three tasks, with varying degree of effectiveness: it converts any CO in the combustion products to CO2. It also facilitates the combustion of any unburned hydrocarbons to carbon dioxide and water. Finally, it also helps to reduce the emissions of nitrogen oxides by transforming them into the harmless nitrogen (N2). Because the proper functioning of the catalytic converter is destroyed by lead, the adoption of catalytic converters to. | Water Pollution in India An Economic Appraisal M.N. Murty and Surender Kumar Introduction Water pollution is a serious problem in India as almost 70 per cent of its surface water resources and a growing percentage of its groundwater reserves are contaminated by biological toxic organic and inorganic pollutants. In many cases these sources have been rendered unsafe for human consumption as well as for other activities such as irrigation and industrial needs. This shows that degraded water quality can contribute to water scarcity as it limits its availability for both human use and for the ecosystem. In 1995 the Central Pollution Control Board CPCB identified severely polluted stretches on 18 major rivers in India. Not surprisingly a majority of these stretches were found in and around large urban areas. The high incidence of severe contamination near urban areas indicates that the industrial and domestic sectors contribution to water pollution is much higher than their relative importance implied in the Indian economy. Agricultural activities also contribute in terms of overall impact on water quality. Besides a rapidly depleting groundwater table in different parts the country faces another major problem on the water front groundwater contamination a problem which has affected as many as 19 states including Delhi. Geo-genic contaminants including salinity iron fluoride and arsenic have affected groundwater in over 200 districts spread across 19 states. Water as an environmental resource is regenerative in the sense that it could absorb pollution loads up to certain levels without affecting its quality. In fact there could be a problem of water pollution only if the pollution loads exceed the natural regenerative capacity of a water resource. The control of water pollution is therefore to reduce the pollution loads from anthropogenic activities to the natural regenerative capacity of the resource. The benefits of the preservation of water quality are manifold. Not .
