Saturday, November 16, 2019

The History Of Water Pollution Environmental Sciences Essay

The History Of Water Pollution Environmental Sciences Essay Water is an important natural resource upon which all the living beings rely for their existence and growth. Nature has blessed the earth with uncountable water resources but usable quantity is limited. Hence, it is important to use water sparingly. The irony is, human activities result is high water pollution which further shortens the water supply for use. Water Pollution In an age when man  has forgotten his origins and is blind even to his most essential needs for survival, water along with other resources has become the  victim of his indifference (Carson, 2002, p. 39). Water is considered to be most crucial one among all the worlds natural resources. Although it covers the largest part of the earths surface (70%), yet it is the limiting factor most of the times. This is because most of this water is not available for use in agriculture or for other human needs due to the presence of significant amounts of mineral salts and heavy metals that make water unfit for use. In each home of an American in New York, 99 gallons of water is an average daily requirement (Fishman, 2012). Water consumption increases by a factor of 2-3% each year while the fresh water total supply remains comparatively constant (Dowdeswell, 1996). Thus, the demand of water is a big dilemma today. A major problem related to water is the issue of water pollution. It is basically the contamination of water with pollutants that may be from human, animal or industrial origin. Natural as well as anthropogenic activities lead to the spoilage of rivers, streams and ground water. This polluted water may also move from one place to another leading to water pollution at greater level (Chiras, 2012). Pollutants in surface waters can be of organic or inorganic nature. Processed or un-processed waste material from either animal or human origin can be released into water ways by waste disposal plants etc. Oil spills are also major contributors of water pollution that give rise to organic pollutants. When water gets saturated with this organic waste, bacteria begin to multiply rapidly. Because of the metabolic activity of the micro-organisms, oxygen gets depleted in such water reservoirs. Oxygen depletion may prove lethal to the life of bodies that rely on oxygen for living. The oxygen level in such bodies can be maintained if the organic influx in such water resources is controlled or minimized. The inorganic pollutants in surface water are basically the nitrates or phosphates which increase the plant growth that lead to inhibition of aquatic life. This is because when plants die, their decay leads to oxygen depletion which effects the aquatic environment greatly. Another important phenomenon related to water pollution is eutrophication which is the deposition of nutrients in lakes. These nutrients come from both natural and human sources and may result in aging of lakes prematurely (Chiras, 2012). Some man made products like plastics, medical wastes and sewage sludge also add significant amount of pollutants to the water. Plastic, because of being resistant to degradation is a great environmental hazard. Although direct dumping of sewage is controlled to a great extent, yet a lot of waste is being introduced into oceans and rivers by the sewage treatment plants (Chiras, 2012). Water may also contain infectious pathogenic micro-organisms that may lead to water-borne disease and ultimately deaths. Parasites as well as bacteria seeping into drinking water may lead to chronic diarrhoea, severe infections of ear and stomach diseases (Duhigg, 2009). Contamination of both ground and surface water through chemical pollutants such as pesticides increases production of carcinogens in the public water supplies. According to National Cancer Institute, the danger of cancer from the consumption of contaminated water will increase greatly in future. A study in Holland supported the view that cancer may be caused because of pollution of waterways. Cities which get water from the rivers have a higher mortality rate than those who use water from less susceptible sources like wells. Arsenic is the major pollutant in polluted waters that leads to cancer (Carson, 2002). Pollution control is the need of today to protect human and animal life from the disasters caused by water pollutants. The control can be imposed by two ways: either by the elimination of contaminants from various sources or by adoption of ways that prevent pollution. Legislative control for addressing the problem of water pollution is being applied on the factories and sewage plants. However, no significant improvement in pollution control has been achieved through this way as the pollution from the streets, farm fields and lawns equalizes the industrial pollution. Control of such wastes is although in infancy yet it is gaining popularity as many cost effective methodologies are present to deal with such wastes. The U. S. government as well as some other states have proven to be successful in addressing ground water pollution. This is because ground water is the major source of drinking water in most of the regions. One pollution control strategy is the treatment of the sewage water. In the first phase, larger particles and particulate organic matter is filtered out of the sewage water. The second stage involves the treatment of the sewage water to remove the organic matter that contains significant amount of nitrogen and phosphorus. This treatment involves the use of bacteria or other decomposers. The third and last treatment is ensuring that the sewage water quality is sustained to the level of drinking water (Chiras, 2012). This is accomplished by increasing the Biological Oxygen demand (BOD) and decreasing the Chemical Oxygen Demand (COD) of the sewage water. Recently, a marine biologist Dr. Widder has come up with a technology to fight water pollution through the use of bioluminescent bacteria. These bacteria make use of light for food, predation and finding partners for mating as part of their normal activity. Dr. Widder performed a study in the Indian River Lagoon which according to scientists is valuable and at the same time the most threatened ecosystem of Florida. In her laboratory, she mixed the sediment samples from the estuary with a bioluminescent bacterium, Vibrio fischeri. The concentration of toxic pollutants in the sediments was monitored through the use of photometer that measured the light emitted by the bacteria. It revealed that to what extent and in what time the light fades away as the bacteria get killed by the chemicals. An estimate of the pollutant level in the sediments better indicates the estuarys health status as compared to direct measurement of chemicals in water. Greater concentration of heavy metals like phosphorus and nitrogen were observed to be present in the sediment samples which stimulate the algal growth. These algae affect the estuary life by depleting oxygen. Dr. Widder has also arranged sensors around the estuary that can provide data in real time which along with the sediment toxicity can trace the path of the pollution source. This method is far more cheap and robust than the traditional practice of taking samples to labs for purpose of analysis (Olsen, 2011). Other than these measures, there is a need of shift of human activities towards the ones that are eco-friendly. Biodegradable plastic should be produced by most of the factories and industries instead of non-degradable plastic that is toxic for health. Moreover, oil spills should be removed from oceans through use of bacteria which can degrade the organic compounds in those oil spills. Better and more economic water treatment strategies should be devised in the future to deal with polluted water. Moreover, ways should be discovered to overcome the shortage of water in near future.

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