الفهرس | Only 14 pages are availabe for public view |
Abstract Water pollution is most often due to human activities. The major ones are indiscriminate disposal of industrial, municipal and domestic wastes in water channels, rivers, streams and lakes, etc. (Kahlown and Majeed., 2003). An estimated 2 million tons of sewage and other effluents are discharged into the world’s waters every day. In developing countries the situation is worse where over 90% of raw sewage and 70% of untreated industrial wastes are dumped into surface water sources.In addition to the industrial wastes, domestic and municipal wastes also pose a serious threat to water (Anonymous.,2010). Like industrial wastes, domestic wastes containing household effluent and human wastes are discharged directly to a natural drain or water body and open or agricultural land. In some cases there are seweage collecting systems, normally discharging to the nearest water body but collecting systems cover less than 50% in many urban cities and only about 10% of the collecting sewages are treated effectively. Another strong source of water pollution is the extensive use of agrochemicals in agriculture (WWF.,2007). |