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====Arsenosis in China====
 
====Arsenosis in China====
[[File:UNN_Medical_Geology_Fig_5.png|thumb|400px|{{figure number|5}}Hyperkeratosis/Ulceration of the Foot and Hands and Hair Fall-Out.<ref name=Wuyi>Wuyi, W., Y. Linsheng, H. Shaofan, and T. Jian’an, 2003. Mitigation of Endemic Arsenocosis with Selenium: an Example from China. HCWSkinner ARBerger, 51–56.</ref>]]
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[[File:UNN_Medical_Geology_Fig_5.png|thumb|400px|{{figure number|5}}Hyperkeratosis/Ulceration of the Foot and Hands and Hair Fall-Out.<ref name=Wuyi>Wuyi, W., Y. Linsheng, H. Shaofan, and T. Jian’an, 2003, Mitigation of endemic Arsenocosis with Selenium: an example from China: HCWSkinner ARBerger, p. 51–56.</ref>]]
    
Arsenosis refers to a range of adverse health effects caused by the intake of arsenic into the body system above the recommended values of 50μg/l.
 
Arsenosis refers to a range of adverse health effects caused by the intake of arsenic into the body system above the recommended values of 50μg/l.
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In Guizhou Province, China, the cool, damp autumn weather forces villagers to bring their harvest of chili peppers and corn indoors to dry. They hang the peppers over unvented stoves which were formally fueled by wood. But, due to the destruction of forests, wood became scarce; so, the villagers turned to the plentiful outcrops of [[coal]] for heating, cooking and drying their harvests.<ref name=Fnklman2010a /> Unknowingly to them, mineralizing solutions in this area had deposited enormous concentrations of arsenic − up to 35,000 ppm − and other trace elements on the coals. It should be noted that normal coals have arsenic concentration of 20 ppm. Consumption of the chili peppers dried over these arsenic-rich coals exposed the natives to arsenosis. The dried chili peppers contained up to 500 ppm of arsenic whereas normal chili peppers contain less than 1 ppm of arsenic.<ref name=Wuyi /> In addition, inhalation of arsenic-laden indoor air derived from coal combustion has increased the toll of arsenic poisoning in the region.<ref name=Fnklman2005 />
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In Guizhou Province, China, the cool, damp autumn weather forces villagers to bring their harvest of chili peppers and corn indoors to dry. They hang the peppers over unvented stoves which were formally fueled by wood. But, due to the destruction of forests, wood became scarce; so, the villagers turned to the plentiful outcrops of [[coal]] for heating, cooking and drying their harvests.<ref name=Fnklman2010a /> Unknowingly to them, mineralizing solutions in this area had deposited enormous concentrations of arsenic—up to 35,000 ppm—and other trace elements on the coals. It should be noted that normal coals have arsenic concentration of 20 ppm. Consumption of the chili peppers dried over these arsenic-rich coals exposed the natives to arsenosis. The dried chili peppers contained up to 500 ppm of arsenic whereas normal chili peppers contain less than 1 ppm of arsenic.<ref name=Wuyi /> In addition, inhalation of arsenic-laden indoor air derived from coal combustion has increased the toll of arsenic poisoning in the region.<ref name=Fnklman2005 />
    
Chemical and mineralogical tests conducted showed that there were many arsenic-bearing minerals in the coals, although, much of the arsenic is bound to the organic matrix of the coals. This observation presented two problems namely: (1) since arsenic is bound to the organic matrix, conventional reduction methods of removing arsenic was ineffective; (2) the visually observable pyrite on the coal samples was not reliable in establishing arsenic-rich samples.
 
Chemical and mineralogical tests conducted showed that there were many arsenic-bearing minerals in the coals, although, much of the arsenic is bound to the organic matrix of the coals. This observation presented two problems namely: (1) since arsenic is bound to the organic matrix, conventional reduction methods of removing arsenic was ineffective; (2) the visually observable pyrite on the coal samples was not reliable in establishing arsenic-rich samples.
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{| class="wikitable"
 
{| class="wikitable"
 
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|+ Table 3: Effects of Arsenic at various organs.<ref name=Htton />
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|+ {{table number|3}}Effects of Arsenic at various organs.<ref name=Htton />
 
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! Organ Affected || Effects
 
! Organ Affected || Effects
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To help solve this problem, villagers were supplied with field test kits to ascertain the arsenic content of coals in the field before use in their unvented stoves. Thus, chili peppers dried over the unvented stoves were free from arsenic contamination.
 
To help solve this problem, villagers were supplied with field test kits to ascertain the arsenic content of coals in the field before use in their unvented stoves. Thus, chili peppers dried over the unvented stoves were free from arsenic contamination.
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Arsenosis is also reported in Inner Mongolia Autonomous Region of China. It is caused by the contamination of surface and groundwater resources by arsenic derived from high- arsenic minerals. Chifeng City in Kosk Teng County in eastern Inner Mongolia is the most affected in this region. It is located on the slope of a mountain with arsenopyrite deposits. The weathering of arsenopyrite (FeAsS) deposits releases arsenic into the groundwater and surface water bodies. The groundwater was delivered to the surface through springs and wells. Out of 34 wells investigated, arsenic concentration between 0.16 mg/l to 0.45 mg/l was observed by Selinus et al.<ref name=Setal2010 /> 22 persons out of 45 persons tested positive to minor arsenosis.<ref name=Setal2010 />
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Arsenosis is also reported in Inner Mongolia Autonomous Region of China. It is caused by the contamination of surface and groundwater resources by arsenic derived from high-arsenic minerals. Chifeng City in Kosk Teng County in eastern Inner Mongolia is the most affected in this region. It is located on the slope of a mountain with arsenopyrite deposits. The weathering of arsenopyrite (FeAsS) deposits releases arsenic into the groundwater and surface water bodies. The groundwater was delivered to the surface through springs and wells. Out of 34 wells investigated, arsenic concentration between 0.16 mg/l to 0.45 mg/l was observed by Selinus et al.<ref name=Setal2010 /> 22 persons out of 45 persons tested positive to minor arsenosis.<ref name=Setal2010 />
    
====Water purification technologies to remove arsenic from water====
 
====Water purification technologies to remove arsenic from water====

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