Water Pollution and Treatment Technologies

Abstract

Water is a source of life and regarded as the most essential of natural resources. Water covers most of our; however, approximately 98% of this water is seawater and is unusable for drinking because of the high concentration of salt. About 2% of the planet’s water is fresh, but 1.6 % is locked up in polar ice caps and glaciers. Another 0.36 %is found underground in aquifers and wells. Therefore, only about 0.036% of the planet’s total water supply is accessible in lakes and rivers. WHO/UNICEF survey states that in 45 developing countries, women and children bear the primary responsibility for water collection in the vast majority (76%) of households. This is time not spent working at an income-generating job, caring for family members, or attending school [1]. Furthermore, existing freshwater resources are gradually becoming polluted and unavailable due to human or industrial activities. The increasing contamination of freshwater systems with thousands of industrial and natural chemical compounds is one of the key environmental problems facing humanity worldwide [2]. The everincreasing world populations and rapidly advancing industrialization is causing more demand than ever for the dwindling supply of water, which makes it precious in more and more countries. In some parts of the world, water is a crucial commodity. Recently, a paper published in Nature indicated that 80% of the world’s population is exposed to high levels of threat to water security [3]. A growing number of contaminants are entering water supplies from industrialization and human activity like heavy metals, dyes; pharmaceuticals; pesticides, fluoride, phenols, insecticides, pesticides and detergents. In the case of pharmaceuticals, personal care products, hormones, pesticides, and other chemical compounds that are released into the water supply. Unprecedented health hazards are coming to light that did not previously exist resulting in an increased need for additional legislature [2]. Many water pollutants remain to be addressed, due to rapid industrialization new chemical compounds are continuously being developed and brought to the market and sooner or later they will emerge into the aquatic systems. Additionally water borne pathogenic microorganisms are ubiquitous throughout the world. These pathogenic microorganisms enter waterways through untreated sewage, storm drains, septic tanks, runoff from farms, and from various industries, especially the tanning and meat packaging industries. Major sources of water pollution are showed in Figure 1. Emerging pollutants detected in water may have adverse effects on human health and aquatic ecosystems. Clean water that is free of toxic chemicals and pathogens is essential to human health. On top of these concerns, contamination of water is a big concern after a natural disaster. Natural disasters(e.g., tsunamis, earthquakes, hurricanes, floods, and volcanoes)can influence water quality on a grand scale.