Little attention was paid to pollution and environmental issues in Pakistan until the early 1990s. Related concerns, such as sanitation and potable water, received earlier scrutiny. In 1987 only about 6 percent of rural residents and 51 percent of urban residents had access to sanitary facilities in 1990 a total of 97.6 million Pakistanis, or approximately 80 percent of the population, had no access to flush toilets. Greater success has been achieved in bringing potable water within reach of the people nearly half the population enjoyed such access by 1990. However, researchers at the Pakistan Medical Research Council, recognizing that a large proportion of diseases in Pakistan are caused by the consumption of polluted water, have been questioning the "safe" classification in use in the 1990s. Even the 38 percent of the population that receives its water through pipelines runs the risk of consuming seriously contaminated water, although the problem varies by area. In Punjab, for example, as much as 90 percent of drinking water comes from groundwater, as compared with only 9 percent in Sindh.

The central government's Perspective Plan (1988-2003) and previous five-year plans do not mention sustainable development strategies (see Development Planning , ch. 3). Further, there have been no overarching policies focused on sustainable development and conservation. The state has focused on achieving selfsufficiency in food production, meeting energy demands, and containing the high rate of population growth, not on curtailing pollution or other environmental hazards.

In 1992 Pakistan's National Conservation Strategy Report attempted to redress the previous inattention to the nation's mounting environmental problem. Drawing on the expertise of more than 3,000 people from a wide array of political affiliations, the government produced a document outlining the current state of environmental health, its sustainable goals, and viable program options for the future (see National Conservation Goals , this ch.).

Of special concern to environmentalists is the diminishing forest cover in watershed regions of the northern highlands, which has only recently come under close scrutiny. Forest areas have been thoughtlessly denuded. Deforestation, which occurred at an annual rate of 0.4 percent in 1989-90, has contributed directly to the severity of the flooding problem faced by the nation in the early 1990s.

As industry has expanded, factories have emitted more and more toxic effluents into the air and water. The number of textile and food processing mills in rural Punjab has grown greatly since the mid-1970s, resulting in pollution of its rivers and irrigation canals. Groundwater quality throughout the country has also suffered from rapidly increasing use of pesticides and fertilizers aimed at promoting more intensive cropping and facilitating self-sufficiency in food production.

The National Conservation Strategy Report has documdf4 umented how solid and liquid excreta are the major source of water pollution in the country and the cause of widespread waterborne diseases. Because only just over half of urban residents have access to sanitation, the remaining urban excreta are deposited on roadsides, into waterways, or incorporated into solid waste. Additionally, only three major sewage treatment plants exist in the country two of them operate intermittently. Much of the untreated sewage goes into irrigation systems, where the wastewater is reused, and into streams and rivers, which become sewage carriers at low-flow periods. Consequently, the vegetables grown from such wastewater have serious bacteriological contamination. Gastroenteritis, widely considered in medical circles to be the leading cause of death in Pakistan, is transmitted through waterborne pollutants (see Health and Welfare , this ch.).

Low-lying land is generally used for solid waste disposal, without the benefit of sanitary landfill methods. The National Conservation Strategy has raised concerns about industrial toxic wastes also being dumped in municipal disposal areas without any record of their location, quantity, or toxic composition. Another important issue is the contamination of shallow groundwater near urban industries that discharge wastes directly into the ground.

Water in Karachi is so contaminated that almost all residents boil it before consuming it. Because sewerage and water lines have been laid side by side in most parts of the city, leakage is the main cause of contamination. High levels of lead also have been found in water in Islamabad and Rawalpindi.

Air pollution has also become a major problem in most cities. There are no controls on vehicular emissions, which account for 90 percent of pollutants. The National Conservation Strategy Report claims that the average Pakistani vehicle emits twenty-five times as much carbon monoxide, twenty times as many hydrocarbons, and more than three and one-half times as much nitrous oxide in grams per kilometer as the average vehicle in the United States.

Another major source of pollution, not mentioned in the National Conservation Strategy Report, is noise. The hyperurbanization experienced by Pakistan since the 1960s has resulted in loose controls for heavy equipment operation in densely populated areas, as well as in crowded streets filled with buses, trucks, automobiles, and motorcycles, which often honk at each other and at the horse-drawn tongas (used for transporting people) and the horse-drawn rehras (used for transporting goods).

Data as of April 1994