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Mercury Pollution

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Mercury Pollution

  1. 1. Mercury Pollution Obianuju Ifesiokwu Cyril Iyasele December 7, 2010
  2. 2. Outline  Introduction  Mercury in the environment  Exposure to mercury  Effects of mercury on human health and environment  Laws and regulations on mercury  Remediation processes of mercury-contaminated sites  Case Study  Minamata Mercury Pollution
  3. 3. Introduction
  4. 4. Introduction  Mercury is the most hazardous metal for human health and environment  Has high toxicity, volatility  Tendency to bio-accumulate in human body  Mercury is on the priority list of 129 chemical substances by US EPA
  5. 5. Introduction  Elemental mercury, although a metal, is unique since it is a liquid at normal temperature  Its high specific gravity and electrical conductivity, has brought about its widespread use in industries  Industrial facilities use mercury in their processes / products  chlor-alkali plants  thermometers, barometers, fluorescent light
  6. 6. Introduction  Both inorganic and organic mercury can cause serious health effects  Organic forms of mercury are generally more toxic than inorganic forms  It is possible for inorganic mercury to be biologically transformed into organic mercury  Therefore, it is important to control inorganic mercury leaching from mercury containing wastes
  7. 7. Introduction  Inappropriate waste dumping during the early stages of industrialization resulted in mercury contamination in soil  In Taiwan, spills, leaks and accidental discharges of mercury containing chemicals have contaminated soil at several sites  Injuries by mercury toxicity have been observed in Japan, Iraq, Pakistan and NM of the United States
  8. 8. Mercury in the environment
  9. 9. Mercury In The Environment  Sources of mercury emissions could be placed in three categories:  natural  anthropogenic  re-emitted sources  Mercury re-emission is the remobilization of settled mercury
  10. 10. Mercury In The Environment Natural sources of mercury emission  Degassing from mercury mineral deposits  Degassing from mercury contaminated aquatic and terrestrial systems  Volcanic emissions  Forest fires
  11. 11. Mercury In The Environment Anthropogenic sources of mercury emission  Solid waste incineration (municipal and medical wastes)  Coal and oil combustion  Pyrometallurgical processes (iron, lead, and zinc)  Production of mercury and gold Among these sources, coal combustion and solid waste incineration account for more than half of the total global emissions
  12. 12. Mercury In The Environment  All over the world, other important industrial sources of mercury emissions into the environment include the manufacture of:  cement  electrical apparatus  pulp and paper  thermometers and fluorescent lamps  In the United States, it is estimated that about 97% of total anthropogenic mercury emissions come from combustion and industrial sources
  13. 13. Exposure to mercury
  14. 14. Exposure To Mercury  Mercury in the air eventually settles into water or onto land where it can be washed into water  Once deposited, certain micro- organisms can change it into methylmercury  This highly toxic form of mercury builds up in fish, shellfish and animals that eat fish
  15. 15. Exposure To Mercury
  16. 16. Exposure To Mercury  Methylmercury builds up more in some types of fish and shellfish than others  The levels of methylmercury in fish and shellfish depend on  what they eat  how long they live  how high they are in the food chain  Fish and shellfish are the main sources of methylmercury exposure to humans
  17. 17. Exposure To Mercury  Another less common exposure to mercury that can be a concern is breathing mercury vapor  These exposures can occur when elemental mercury or products that contain elemental mercury break and release mercury to the air  Particularly in warm or poorly-ventilated indoor spaces
  18. 18. Effect of Mercury on Human Health & Environment
  19. 19. Effect of Mercury on Human Health & Environment  Mercury exposure at high levels can harm the:  brain, heart  kidneys, lungs  immune system of people of all ages  High levels of methylmercury in the bloodstream of unborn babies and young children may harm the developing nervous system  Making the child less able to think and learn
  20. 20. Effect of Mercury on Human Health & Environment  The factors that determine how severe the health effects are, from mercury exposure, include:  the chemical form of mercury  the dose  the age of the person exposed (the fetus is the most susceptible)  the duration of exposure  the route of exposure - inhalation, ingestion, dermal contact, etc  the health of the person exposed
  21. 21. Effect of Mercury on Human Health & Environment Ecological effects of mercury  Birds and mammals that eat fish are more exposed to mercury than other animals in ecosystems  Similarly, predators that eat fish-eating animals may be highly exposed  At high levels of exposure, methylmercury's harmful effects on these animals include:  death, reduced reproduction  slower growth and development, and abnormal behavior
  22. 22. Effect of Mercury on Human Health & Environment
  23. 23. Effect of Mercury on Human Health & Environment  EPA works with the U.S. Food and Drug Administration (FDA) and with states and tribes to issue advice to women  who may become pregnant  pregnant women, nursing mothers  and parents of young children about how often they should eat certain types of commercially-caught fish and shellfish  EPA releases an annual summary of information on locally-issued fish advisories and safe-eating guidelines to the public
  24. 24. Laws & Regulations on Mercury
  25. 25. Laws & Regulations on Mercury  Laws and regulations are a major tool in protecting the environment  Congress passes laws (statutes) that govern the United States  To put those laws into effect, Congress authorizes certain government agencies, including the Environmental Protection Agency (EPA) to create and enforce regulations  Regulations provide specific rules and details for how to put the law into practice
  26. 26. Laws & Regulations on Mercury Under certain Federal environmental statutes, such as the CAA, CWA, and RCRA,  EPA has the responsibility to develop regulations to control some mercury emissions to air, water, or from wastes and products  In addition, states also develop regulations to address mercury emissions
  27. 27. Laws & Regulations on Mercury Mercury-Specific Laws Mercury Export Ban Act of 2008  President George W. Bush signed into law the Mercury Export Ban Act of 2008 on October 14, 2008  The Act includes provisions on both mercury exports and long-term mercury management and storage  U.S. is ranked one of the world‘s top exporters of mercury. Thus, implementation of the act will remove a significant amount of mercury from the global market
  28. 28. Laws & Regulations on Mercury Mercury-Containing and Rechargeable Battery Management Act of 1996 (Battery Act)  The statute applies to battery and product manufacturers, battery waste handlers, and certain battery and product importers and retailers  Phases out the use of mercury in batteries  Provides for the efficient and cost-effective disposal of used:  nickel cadmium (Ni-Cd) batteries  small sealed lead-acid (SSLA) batteries  certain other regulated batteries
  29. 29. Laws & Regulations on Mercury Other Environmental Laws that Limit Mercury Exposures Clean Air Act  The CAA regulates 188 air toxics, also known as ―hazardous air pollutants‖  Mercury is one of these air toxics The Clean Air Mercury Rule  EPA regulated mercury emissions from coal-fired power plants
  30. 30. Laws & Regulations on Mercury Clean Water Act  Under the CWA, states adopt water quality standards for their rivers, streams, lakes, and wetlands  These standards identify levels for pollutants, including mercury, that must be met in order to protect human health, fish, and wildlife Resource Conservation and Recovery Act  RCRA requires that EPA manage hazardous wastes, including mercury wastes, from the time they are generated, through storage and transportation, to their ultimate treatment and disposal
  31. 31. Laws & Regulations on Mercury Safe Drinking Water Act  Under the SDWA, EPA sets standards for drinking water that apply to public water systems  These standards protect people by limiting levels of mercury and other contaminants in drinking water  Mercury contamination in drinking water can come from:  erosion of natural deposits of mercury  discharges into water from refineries and factories  runoff from landfills
  32. 32. Remediation Processes of Mercury-Contaminated Sites
  33. 33. Remediation Processes of Mercury-Contaminated Sites  Mercury is persistent in the environment  Effective remedial methods need to be applied to lower mercury levels in heavily contaminated sites In general, four kinds of treatments of contaminated sediment are available:  In situ containment  In situ treatment  Ex situ containment  Ex situ treatment
  34. 34. Remediation Processes of Mercury-Contaminated Sites  Thermal desorption  Usually, an ‗‗ex situ‖ remedial technology  Converts mercurial compounds into the volatile mercury  Considered as a preferred technology, due to more safety and less emission of treating substance  Stabilization / Solidification  Vitrification  Soil flushing  Soil washing
  35. 35. Remediation Processes of Mercury-Contaminated Sites Capping  In situ capping (ISC) is on site placement of proper covering material over contaminated sediment in aquatic systems  In ex situ capping (ESC), contaminated sediment is dredged and relocated to another site, where one or multiple isolating layers are placed over the sediment
  36. 36. Remediation Processes of Mercury-Contaminated Sites  Source Control  Dredging  Natural Attenuation
  37. 37. Case Study
  38. 38. Case Study Minamata Mercury Pollution  Minamata - a fishing village in the south of Japan, on the Minamata bay, is the site of one of humanity‘s most tragic cases of industrial pollution  It was caused by the release of methylmercury in the industrial wastewater from Chisso Corporation's chemical factory
  39. 39. Case Study Root Cause Assessment of Impact of Minamata Symptoms of Minamata Minamata Pollution Pollution Disease  Indiscriminate dumping of  Huge quantities of mercury General wastewater detected in fish, shellfish and  Muscle weakness sludge in Minamata bay  Absence of wastewater  Damage to hearing, treatment facility  Stigmatization and vision and speech discrimination against  Crippling hands  Economic clout of Chisso patients and feet Corporation  Dredging and reclamation done to remove the toxic Extreme Cases sludge from the Minamata  Paralysis bay  Coma  Death
  40. 40. Summary  Introduction to mercury pollution  Mercury in the environment  Exposure to mercury  Effects of mercury on human health and environment  Laws and regulations on mercury  Remediation processes of mercury-contaminated sites  Case Study  Minamata Mercury Pollution
  41. 41. References  Park, K.S., et al., 2007. Emission and speciation of mercury from various combustion sources. Powder Technology 180, 151-156.  Yudovich, Ya.E, Ketris, M.P., 2005. Mercury in coal: a review Part 2. Coal use and environmental problems. Coal Geology 62, 135-165.  Mukherjee, A.B., et al., 2004. Mercury in waste in the European Union: sources, disposal methods and risks. Resources Conservation and Recycling 42, 155-182.  Randall, P, Chattopadhyay, S., 2004. Advances in encapsulation technologies for the management of mercury-contaminated hazardous wastes. Journal of Hazardous Materials B114, 211-223.  Wasay, S.A., et al., 1995. Remediation of a soil polluted by mercury with acidic potassium iodide. Journal of Hazardous Materials 44, 93-102.  Matlock, M.M., et al., 2003. Irreversible binding of mercury from contaminated soil. Advances in Environmental Research 7, 347-352.  Yudovich, Ya.E, Ketris, M.P., 2005. Mercury in coal: a review Part 1. Geochemistry. Coal Geology 62, 107-134.  Li, X.B., Feng, G.L., Qiu, L.H., Shang, Z.G., Li., 2009. Mercury pollution in Asia: A review of the contaminated sites. Journal of Hazardous Materials 168, 591-601.  Kudo, A.Y., Fujikawa, S., Miyahara, J., Zheng, H., Takigami, M., Sugahara, T., Muramatsu., 1998. Lessons from minamata mercury pollution, Japan — After a continuous 22 years of observation. Water Science and Technology 38, 187-193.  Nguyen, H. T., et al., 2008. Mercury in air in an area impacted by strong industrial activities. Chemosphere 71, 2017-2029.  Harris, R. C., 1971. Ecological implication of mercury pollution in aquatic systems. Biological Conservation 3, 279-283.  US EPA, 2010. <http://www.epa.gov/mercury/index.html>.
  42. 42. References  Piao, H., Bishop, P.L., 2004. Stabilization of mercury-containing wastes using sulfide. Environmental Pollution 139, 498-506.  Steven, M.J., 1995. The materials flow of mercury in the United States. Resources, Conservation and Recycling 15, 145-179.  Wang, Q., Kim, D., Dionysiou, D.D., Sorial, G.A., Timberlake, D., 2004. Sources and remediation for mercury contamination in aquatic systems – a literature review. Environmental Pollution 131, 323-336.  Chang, T.C, Yen, J.H., 2005. On-site mercury-contaminated soils remediation by using thermal desorption technology. Journal of Hazardous Materials B128, 208-217.  Devasena, M., Nambi, I.M., 2010. Migration and entrapment of mercury in porous media. Journal of Contaminant Hydrology 117, 60-70.  Wasay, S.A., Anfalk, P., Tokunaga, S. 1995. Remediation of a soil polluted by mercury with acidic potassium iodide. Journal of Hazardous Materials 44, 93-102.  Hylander, L.D, Goodsite, M.E., 2006. Environmental costs of mercury pollution. Science of the Total Environment 368, 352-370.  Navarro, A., Canadas, I., Martinez, D., Rodriguez, J., Mendoza, J.L. 2009. Application of solar thermal desorption to remediation of mercury-contaminated soils. Solar Energy 83, 1405-1414.  Pavlish, J.H., Hamre, L.L., Zhuang, J. 2010. Mercury control technologies for coal combustion and gasification systems. Fuel 89, 838-847.  Chang, C.Y., Hsu, C.P., Jann, J.S., Chen, Y.W., Shih, Y.C., Mao, C.F., Lin, W.Y., Lin, K.L., Wu, Y.M., 1993. Stabilization of mercury- containing sludge by a combined process of two-stage pre-treatment and solidification. Journal of Hazardous Materials 35, 73-88.

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