Pyrite Essay Examples

Iron And Human Health

Abstract
Pyrite is the most common sulfide mineral. The iron found in pyrite and water can affect human health. From the perspective of human health, Pyrite has been listed as dangerous. The acid mine waters linked to sulfide mine tailings are the prime sources of pyrite. The paper looks at the harmful effects of iron present in pyrite and water on human health.

Introduction

Pyrite or FeS2 is a common sulfide mineral that carries bright golden color and because of its brilliant metallic luster, it is a distinctive mineral. Acid mine waters are its main source, and those Acid waters are related to pyrite oxidation. It leads to solubilization of toxic heavy metals causing their dispersal in the environment. The pyrite in coals and water is a major health problem affecting millions of people. Pyrite can be a very hazardous mineral. The oxidation of pyrite, when catalyzed by certain bacteria, can release toxic metals and metalloids. Acid waters can lead to acid rain and solubilization of toxic heavy metals that can dispersed in the environment.
One of the major gift of pyrite to the human society is fire. When pyrite is struck against a hard surface, sparks get created, and this is one of the earliest methods of creating flames that is known to the humans. Pyrite is derived from the Greek phrase, ‘pyrite lithos,’ which means stone that strikes fire. The bright golden luster of pyrite was mistaken for gold in the early days. However, Pyrite has flat crystal faces and is much harder than gold. Its presence in rock points to the presence of other metal ores and hydrothermal minerals that carry significant value (Pyrite, 2015).
Acid mine drainage Acid mine drainage (AMD) is a dangerous pollution hazard that can pollute surrounding groundwater and surface water, as well as soil. A mine site employs the technology of geology, hydrology, and mining and leads to the formation of acid mine drainage. Sulfide minerals, such as pyrite or iron sulfide are the main sources for an acid generation that get decomposed in air and water. The waste rock from the mine or tailings carry the sulfide minerals, and if the water penetrates pyrite-laden rock in the presence of air, it can get acidified, carrying a pH level of 2 or 3. The higher level of acidity in the water can lead to corrosion of piers, boat hulls, pumps, etc. It can destroy living organisms. The water is simply not fit for drinking or recreational use (Mining, 2015).
The high amounts of Fe from pyrite can retard nitrification. However, the exact mechanism behind as to how pyrite constrains nitrification is still not clear. The effect of pyrite is due to the toxic action of sulfides, oxidized forms of the sulfides and presence of Fe2+ ions. The subtropical and tropical acid soils carry high levels of Fe oxides, and it is strongly hypothesized that Fe plays a strong role in regulating NO3 acid forest soils (Jiang et al., 2015).

Impact of Site contamination

Iron sulfide minerals are one of the end products of sulfate reduction. From the environmental point of view, two forms of iron sulfide minerals, pyrite and iron sulfide are very important. Soils that contain sulfides are known as ‘sulfidic materials’ and if these soils are exposed to air, they can be damaging, as the exposure results in the oxidation of pyrite. The procedure leads to acid sulfate soil material that can potentially impact on human health and the environment. For example, the sulfuric acid generation can corrode concrete, steel and some aluminum alloys used in buildings and roads. The sulfate soil material and the iron in it can affect plant growth. The pipe drainage systems can get blocked due to the formation of iron oxides. The increased level of soluble metals and acidity will lead to higher plant toxicity and lower farm productivity. The grazing animals will get a higher uptake of aluminum and iron. Acidic waters can enter estuarine, coastal or riverine environments and affect the fish and aquatic life. The lower pasture quality of the acid sulfate soils can lead to a higher uptake of aluminum and iron by grazing animals (Site contamination —acid sulfate soil materials. 2007).
Privately supplied drinking water from bedrock often carries arsenic at levels that are a health concern for humans in Eastern New England. Water from wells in metasedimentary bedrock shows the highest level of arsenic concentrations, suggesting a geologic source. Arsenic is common in groundwater carrying high pH that is related to the age of the groundwater. Those areas that were formerly inundated by seawater undergo Ion exchange, and this can also raise the pH (Ayotte et al., 2003).
How Iron can be damaging Iron does not dissolve easily in water or in dry air. However, in the presence of water and oxygen, iron starts to corrode and the iron elements can get released into the waters. Thus, waters can get iron carbonate. Although Iron is a dietary requirement, but high concentrations of iron in diet can lead to serious health issues. The iron can get stored in the pancreas, the spleen, the liver and the heart. Once those vital organs get injured, it can be complex to cure the ailments that follow. Iron compounds in fact can lead to more serious health problems than elements. For example, water-soluble binary iron compounds can lead to toxic effects that can be lethal.
The human body has limited capacity to get rid of excess iron and the iron is usually eliminated via urine, stool and exfoliation of epidermal cells. Excess of iron storage in the body and exposure of skin to higher level of iron can cause oxidative damage and skin aging. An increased Iron can affect women's health after menopause and lead to breast cancer and heart disease. There is evidence of role of increased iron in osteoporosis, skin aging and hot flashes. Men are not immune to the pathologic effects of iron increase and the incidence of heart disease in men has been linked to higher levels of stored iron (Jian, Pelle & Huang, 2009).
The surrounding rural districts and city of Hanoi around Red River alluvial tract are known for arsenic contamination. The ground waters are rich in iron because of the naturally occurring organic matter. In some of the rural areas, the groundwater is used as drinking water and an analysis of raw groundwater yielded high arsenic levels. The treatment plants for iron removal via aeration and sand filtration lowered the arsenic concentrations. Extracts of sediment samples show a correlation of arsenic and iron and the arsenic in the sediments may be linked to iron oxyhydroxides. The oxidation of sulfide phases could lead to reductive dissolution of iron and release arsenic to the groundwater. The high arsenic concentrations in these areas expose millions of at a considerable risk of arsenic poisoning as they consume untreated groundwater (Berg et al., 2001).
One is well aware of the harmful effects on health when inhaling coal dust and there is a wide prevalence of lung disease among miners. The bioavailable iron content of the coal can vary with regions. Pyrite is a common component in coal and is known to create reactive oxygen species. This raises concerns for similar reactivity from coal containing higher level of pyrite. Studies show that coals that contain iron carry FeS2 and lead to generation of ROS and degrade RNA. The degradation rate of RNA and generation of ROS increased with greater FeS2. Thus, the pneumoconiosis among coal workers can be correlated to the amount of FeS2. The presence of FeS2 is associated with the toxicity of coal. Already, several occupational risks related to coal mining have been documented and comprise of health problems due to chronic exposure to coal dust. Chronic obstructive pulmonary disease and pneumoconiosis are the most common diseases that are prevalent among the coal miners.
Coal is a variable mixture of inorganic minerals and organic carbon such as clays, quartz, pyrite and carbonates. When different coals are compared for their toxicological potential, the aspects such as generation of reactive oxygen species, cytotoxicity, genotoxicity as well as signs of chemokine, cytokine and oxidative stress are compared. The quartz content in coals and presence of other minerals is correlated to the prevalence of antioxidant production and pulmonary inflammation. The high concentrations of iron in biological systems can lead to oxidation to biomolecules. The iron associated with iron oxides and iron sulfides is one of the key reactant in the devices that can lead to lung injury. Recent studies show that the pyrite content of coal can be attributed to a prevalence of lung disease among coal miners. However, additional factors such as shape, size and presence of other metals may also contribute to the disease prevalence. Arsenic is frequently related with pyrite in coals (Cohn et al., 2006).

Conclusion

Pyrite is among the most abundant metal sulphide that is found on Earth and when exposed to water can create hydrogen peroxide. The aqueous suspensions of pyrite generate hydrogen peroxide which reacts with ferrous iron to form hydroxyl radicals. The formation of hydroxyl radicals leads to oxidative stress and carcinogenesis and the extreme reactivity of OH can lead to several diseases in humans. The pyrite-generated H2O2 can react with ferrous iron on the pyrite surface. Acid mine drainage is a universal problem and leads to not only ecological destruction in watersheds, but also the contamination of human water sources because of the heavy metals such as arsenic, copper, and lead as well as sulfuric acid. The acid generation is very difficult to curb once the acid-generating rock gets crushed and is to the surface environment. The iron sulfide weathers in the air, releasing iron and releasing sulfuric acid. It is the irreversibility of the process and the extreme difficulty of containment that makes the issue a serious one. The iron sulfide weathers in the air, releasing iron and releasing sulfuric acid. The acid mine drainage leads to negative impacts on the river systems and aquatic life, as well as lead to many health issues.

References

Ayotte, J. D., Montgomery, D. L., Flanagan, S. M., & Robinson, K. W. (2003). Arsenic in groundwater in eastern new england: Occurrence, controls, and human health implications. Environmental Science & Technology, 37(10), 2075-2075. doi:10.1021/es026211g
Berg, M., Tran, H. C., Nguyen, T. C., Pham, H. V., Schertenleib, R., & Giger, W. (2001). Arsenic contamination of groundwater and drinking water in vietnam: A human health threat. Environmental Science & Technology, 35(13), 2621-2626. doi:10.1021/es010027y
Cohn, C. A., Laffers, R., Simon, S. R., O’Riordan, T., & Schoonen, M. A. (2006). Role of pyrite in formation of hydroxyl radicals in coal: possible implications for human health. Particle and Fibre Toxicology, 3, 16. doi:10.1186/1743-8977-3-16
Jian, J., Pelle, E., & Huang, X. (2009). Iron and Menopause: Does Increased Iron Affect the Health of Postmenopausal Women? Antioxidants & Redox Signaling, 11(12), 2939–2943. doi:10.1089/ars.2009.2576
Jiang, X., Xin, X., Li, S., Zhou, J., Zhu, T., Müller, C. Wright, A. L. (2015). Effects of fe oxide on N transformations in subtropical acid soils. Scientific Reports, 5, 8615. doi:10.1038/srep08615
Mining. (2015). Retrieved from http://www.pollutionissues.com/Li-Na/Mining.html
Pyrite. (2015). Retrieved from http://www.esci.umn.edu/courses/1001/minerals/pyrite.shtml
Site contamination —acid sulfate soil materials. (2007). Retrieved from http://www.epa.sa.gov.au/xstd_files/Site contamination/Guideline/guide_sc_acid.pdf