Arsenic in Groundwater in Eastern New England - Essay Example

Arsenic in Groundwater in Eastern New England Concerns have been raised with regard to theincreasing concentration of arsenic in groundwater in eastern New England. Drinking water being supplied from solid rock aquifers has levels of arsenic concentration, which can affect human health. Some of the most affected areas in the world are Maine and New Hampshire, in the United States, where arsenic concentrations have been as high as 30 percent (Ayotte, Montgomery and Flanagan 2075). These concentrations mainly affect water from wells in meta-sedimentary bedrock areas where bedrock aquifers generate concentrations of up to 10 micrograms per liter (Ayotte, Montgomery and Flanagan 2075). The relationship between the high pH associated with ground water and the age of groundwater has been associated with the concentration of arsenic in groundwater. Arsenic concentrations in this region have been a subject of study for many researchers, probably, as a result of the possible implications associated with arsenic-concentrated groundwater (USGS 2). This paper will examine the background of this problem while considering previous studies and other sources. An analysis of the possible reasons for the increasing arsenic concentration in eastern New England will be done and this includes anthropogenic and natural sources which will be an important part of this analysis. Human health implications have been a key concern with regard to arsenic concentrations, making it an essential point of focus in this study. Chapter 1: Review and Background of the Problem Arsenic is a widespread element that is traced in groundwater in varying concentrations in the United States (Welch 589). As a result, drinking water in the region contains a substantial concentration of this element, which has raised serious health concerns. This has called for the regulation of drinking water by the Federal as well as State standards that control public water systems (U.S. Environmental Protection Agency 1). The U.S. Environmental Protection Agency (USEPA) has ruled that the standard of arsenic concentration should be between 50 and 10 micrograms per liter. However, moderate to high (10-50 micrograms) arsenic concentrations have been present in groundwater in eastern New England. Moreover, a significant number of wells are above moderate concentrations in New England (Loiselle 5). Many studies on arsenic concentrations in ground water have been unable to establish the source of arsenic; nevertheless, evidence shows that arsenic in New England predominantly originates from natural sources, especially various minerals and rocks found in the region (Reeve 12). However, other studies have linked arsenic concentrations in New England with geologic sources (Hinkle 433). Some studies have associated arsenic concentrations in New England with anthropogenic source such as treated lumber, use of pesticides, and wastes from manufacturing industries, which contaminate ground water (D’Angelo 3). According to Robinson, there is a direct relationship between groundwater fundamental chemistry and the geochemistry associated with “aquifer materials” that the water flows through. The age of these aquifer materials and the length of time during which water has been held in them also has an impact (97). With regard to various studies that have been conducted on the chemistry of the groundwater in New England, the natural chemistry of water has been associated with a partial dependence on the geochemical disposition of bedrock configurations and a partial dependence on the level of “metamorphism of the bedrock” (Robinson 97). These studies have further established that “unconsolidated aquifers” hold freshly recharged ground water and there are similarities in their ion water chemical compositions. However, it has been found that the quality of water in eastern New England is extremely variable and the natural water chemistry of groundwater present is significantly disparate in different wells. Some of the most common anthropogenic water contaminants have been established and include manganese, iron, arsenic and radionuclide (Robinson 99). About 30 percent of the water consumed in New England come from public water systems and is mainly drawn from unconsolidated aquifers. Water supplied by private systems is drawn from bedrock aquifers and comprises almost 20 percent of water consumed in New England. The other 50 percent of New England drinking water comes from surface water sources (U.S.Geological Survey 3). As has been indicated above, there are natural, geologic as well as anthropogenic sources of arsenic that have been found in ground water. In the following section, this paper will examine in detail the sources of arsenic in groundwater in eastern New England. Chapter 2: Analysis of the Problem In this section, the paper will focus on the reasons for the increasing arsenic concentration in ground water, specifically, the natural and anthropogenic sources. Anthropogenic Sources Arsenic has been in use for various industrial purposes in the United States, including the production of glass, wood preservation and many agricultural applications (Welch, Westjohn and Helsel 598). However, glass production and agricultural use have declined over the last few years (Ayotte, Montgomery and Flanagan 2076). According to the US Department of Agriculture, the application of Monosodium methanearsonate (MSMA) in agricultural land was quite common and it was the primary arsenic compound applied on agricultural land by 1996 (US Department of Agriculture 9). Comparatively smaller amounts of ‘disodium methanearsonate (DMSA) and dimethyl arsinic acid (cacodylic acid)’ were applied on agricultural land in the same year. Additionally, arsenic has been an important component of swine and poultry feeds. As a pesticide, inorganic arsenic was commonly used before the 1980s in the United States. This means that a significant amount of it had already been released to the natural environment. The arsenic concentrations found in soil in many areas in the United States, including New England, have been partly attributed to the use of almost 500 hundred KGs per hectare of arsenic on American farms in the 1970s, especially done in apple orchards when apple cultivation was highly prevalent. The use of phosphate fertilizers is also a possible cause of the contamination of ground water with arsenic. This mostly happens when phosphates are applied on arsenic contaminated soil (Peryea and Kammereck 243). The application of phosphates on uncontaminated soil has increased arsenic concentration in groundwater as a result of the release of adsorbed arsenic (Peryea and Kammereck 247). In eastern New England, few agricultural activities have been in control with regard to the use of arsenic compounds on agricultural land, a factor that has intensified arsenic concentrations. As has been found by many studies, while waste disposal has been a great contributory factor in arsenic groundwater concentrations, the arsenic does not arise from waste disposal but more from other components found in waste (Konefes 15). Laboratory evidence has indicated that a great source of arsenic is iron oxide, which has been mobilized in many waste disposal sites, which include some sites in New England that are contaminated with Volatile Organic Compounds (VOCs). Some of these sites lack identified sources of anthropogenic sources of arsenic. High regional arsenic concentrations coincide with agricultural applications, but these agricultural applications are not the direct causes of the concentration (Aschbacher and Feil 149). Ground water is mainly unaffected by arsenic pesticides, rather the disposal of cotton industrial wastes have had a significant effect on arsenic concentration (Konefes 15). The era of the Civil War saw significant impacts on the arsenic concentration on surface, as well as shallow ground water, due to the rampant use of the embalming fluid. Natural Sources Atmospheric Precipitation and Surface Water Some of the possible natural sources of arsenic concentrations in ground water include atmospheric precipitation in areas that have faced environmental pollution and contaminated surface water as well as some aquifer materials. For example, in Washington, arsenic concentration collected in rain and snow was as high as 17 micrograms per liter (Wilkie and Hering 657). Most natural sources of water in the United States, including streams and rivers contain significant concentrations of arsenic, usually more than 10 micrograms per liter. A considerable exception has been surface water originating from geothermal areas where concentration of arsenic has been as high as 1000 micrograms per liter. An example of such an area is the geothermal springs that are found in the Yellowstone National Park (Ball 98). The discharge of geothermal water raises arsenic concentrations to significant levels, often up to as high as 400 micrograms per liter (Wilkie and Hering 658). Examples of rivers that have been affected by these kinds of concentrations include the Madison River and the Missouri river. Geothermal water is the main source of arsenic concentrations in surface water in the United States. In addition to this, arsenic concentrations can be highly increased by water emanating from mineralized drainage areas. Occurrence of Arsenic in Ground Water Some areas such as the Appalachian highlands and the Atlantic plain, experience very low arsenic concentration on their ground water, with close to about 80 percent of their ground water having below 1 microgram per liter concentration. Industrial concentrations have been linked with some high concentration in the Appalachian Highlands and Alabama, arguably as a result of coal mining in some places (Aschbacher and Feil 149). In coal mining drainages, the most common source of arsenic is the pyrite mineral, which contains a huge percentage of most coal. Arsenic concentrations are in Rocky Mountains where interior plains have been associated with higher arsenic concentrations. One of the key natural sources of these concentrations is sulfide minerals, especially in areas such as eastern Wisconsin and Michigan. In these areas, there are consolidated bedrocks that contain more than 6 percent authigenic pyrite, which dispatches significant concentrations of arsenic into the ground water. Marcasite is also a key source of arsenic concentration in New England. High ionic concentrations of arsenic have also been established in “alluvial and glacial aquifers” (Ayotte, Montgomery and Flanagan 2077). Arsenic concentrations have been found in intermountain plateaus. Because of the arid and semi-arid climate in these areas, evaporation concentration of arsenic is prevalent, leading to an increase in the arsenic concentration in shallow ground water. Some of the most affected areas in this respect include eastern California, Utah, Oregon and Nevada (Ayotte, Montgomery and Flanagan 2077). One factor for this is the high pH of the saline ground water, which increases arsenic concentration by inhibiting adsorption. Chapter 3: Implications The high arsenic concentrations in ground water in eastern New England have raised considerable concerns. Usually, water should not contain more than 10 micrograms of arsenic in the United States, as per the 2006 regulation. This was meant to secure consumers from being served with water with arsenic concentrations that can be harmful to their health. However, private groundwater sources have not been put under this regulation and are not liable to comply with any of these federal or state regulations. As has been seen above, about 30 percent of water in the supply system is obtained from unconsolidated aquifers, while 20 percent is acquired form bedrock aquifers, both of which have high levels of arsenic concentration. The rest of the water is obtained from surface water sources, such as rivers and streams, and they are mainly affected by androgenic sources of arsenic. As a result, there are serious impacts that face consumers of drinking water in eastern New England. Therefore, the incomplete protection of the consumers by federal and state standards puts the consumers more at risk of being affected by cancer (USGS 7). As has been found in various studies, the effect of this lack of comprehensive protection by the regulations (since private suppliers do not have to comply with regulations) is that many consumers will end up consuming water that has high levels of arsenic even without their knowledge (Ayotte, Montgomery and Flanagan 2081). According to this study, there is an immense population that consumes water from private suppliers, which usually contains more than 20 micrograms per liter of arsenic concentration. The above study has also found that almost 30 percent of the populations have the chances of consuming water that is contaminated with arsenic, which means that almost thirty percent have the chances of becoming cancer victims. In western counties of Massachusetts, Maine, New Hampshire and Rhode Island, various private wells get water from bedrock aquifers, and these wells have been supplying water to huge populations (Ayotte, Montgomery and Flanagan 2081). An additional indication of this research is that close to 20 percent of the population getting water from private wells in eastern New England has great chances of drinking water containing high levels of arsenic since these water suppliers are not protected. Studies have also indicated that there is even a bigger risk of consumers to be exposed to health hazards due to two reasons. The first reason is that the largest portion of the population that has private supplies providing high arsenic concentrations is found in the east part of New England. The second reason is that this part of New England is the fastest growing in the region, and therefore, private suppliers have continued to be created in these areas of high arsenic concentrations, where arsenic concentrations are above 10 micrograms per liter (Ayotte, Montgomery and Flanagan 2081). Arsenic also exposes consumers to other health problems including stomach problems, reduction in the red blood cells production and skin problems. The use of arsenic compounds on agricultural land has been established as a major cause of serious health problems in human beings both directly and indirectly. Part of the chemical composition of fruits and other agricultural products is determined by the fertilizers that were used in their cultivation. Though quite low, there is a percentage of arsenic that has been said to be passed on to the human body through consumption of fruits that have been cultivated using phosphate fertilizers (Mahimairaja, Bolan and Adriano 13). High levels of toxicity in both soil and plants are passed on to the fruits and later to human beings, exposing them to kidney diseases and affects the circulatory and respiratory systems. As has been seen above, about 30 percent of water in the supply system is obtained from unconsolidated aquifers, while 20 percent is acquired form bedrock aquifers, both of which have high levels of arsenic concentration. The rest of the water is obtained from surface water sources, such as rivers and streams, and they are mainly affected by androgenic sources of arsenic. As a result, there are serious impacts that face consumers of drinking water in eastern New England (Mahimairaja, Bolan and Adriano 14). Consequently, this transfers the risk to human health due to those people who rely on aquatic life such as the fishermen. Chapter 4: Conclusion The concentration of arsenic in water sources in eastern New England, as in many other parts of the United States, is evident. Ground water is obviously one of the largest sources of water that both private and public water supplies use. Surface water is also affected mainly by anthropogenic sources of arsenic. Therefore, one can conclude that the entire population of eastern New England has been exposed to arsenic concentrations above what federal and state regulations recommend. As a result, citizens in this region are exposed to various health risks associated with exposure to arsenic. A comprehensive legal framework or a more effective regulatory structure that protects consumers from these risks should be enforced. Such measures should focus on being in control of both anthropogenic and natural sources of arsenic, which all consumers have been exposed to. Meanwhile, consumers have been left to take their own care in protecting themselves from the health hazards associated with high arsenic concentrations. Read More