Some of the most comprehensive studies of the health impacts of mercury from ASGM have occurred in Madre de Dios. These studies have found elevated concentrations of mercury in mining areas compared to people living in the regional capital of Puerto Maldonado, with 11% of people in mining communities displaying elevated mercury concentrations (> 6.0 mg/g) compared to only 5% in the city [Ashe et al. 2012]. Additionally, several unpublished studies have found the highest concentrations of mercury in indigenous communities far upstream from gold mining.
In addition to the impacts of ASGM on mercury exposure, ASGM also leads to increases in infections diseases such as dengue fever and malaria. This is a direct result of the standing water that pools in mining pits and provides breeding ground for disease-carrying mosquitoes.
OVERVIEW OF MECHANISMS OF MERCURY IMPACT ON PEOPLE
Biological Mechanism:
Mercury binds strongly to sulfhydryl groups on tissue proteins, such as muscle. It also forms a complex with cysteine (an amino acid) to gain access to cells, thereby crossing membranes and the blood-brain barrier. Elemental mercury in the blood brain barrier becomes ionized and gets trapped, causing neurotoxicity.
Mercury binds strongly to sulfhydryl groups on tissue proteins, such as muscle. It also forms a complex with cysteine (an amino acid) to gain access to cells, thereby crossing membranes and the blood-brain barrier. Elemental mercury in the blood brain barrier becomes ionized and gets trapped, causing neurotoxicity.
Biological effects:
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U.S. EPA [2001] reference doses:
Oral reference dose (RfD): The numerical estimate of daily oral human exposure to MeHg which is not likely to cause harmful effects during a lifetime is 0.1 μg/kg body weight/day. Inhalation Reference Concentration (RfC): RfC of elemental mercury is 0.3 µg / m³ of air. Toxicity Overview: Acute versus Chronic Toxicity:
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Reproductive System:
Carcinogenicity:
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Nervous System:
Cardiovascular System:
Immune System:
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Sources
Ashe K (2012) Elevated Mercury Concentrations in Humans of Madre de Dios, Peru. PLoS ONE 7(3): e33305.
Azevedo BF, Furieri LB, Pecanha FM, Wiggers GA, Vassallo PF, Simoes MR, Fiorim J, de Batista PR, Fioresi M, Rossoni L, Stefanon I, Alonso MJ, Salaices M, Vassallo DV (2012) Toxic Effects ofMercury on the Cardiovascular and Central Nervous Systems. J Biomed Biotechnol 2012: 949048.
Branco V, Caito S, Farina M, Teixeira da Rocha J, Aschner M, Carvalho C (2017) Biomarkers of mercury toxicity: Past, present, and future trends. J Toxicol Environ Health B Crit Rev 20(3):119-154.
Clarkson TW and Magos L (2006) The toxicology of mercury and its chemical compounds. Crit Rev Toxicol 36: 609–662.
Hong Y-S, Kim Y-M, Lee K-E (2012) Methylmercury Exposure and Health Effects. J Prev Med Public Health 45:353-363.
National Research Council (US) Committee on the Toxicological Effects of Methylmercury (2000) Toxicological Effects of Methylmercury: 5, Health Effects of Metylmercury. National Academies Press, Washington, DC.
Salonen JT, Seppänen K, Nyyssönen K, Korpela H, Kauhanen J, Kantola M, Tuomilehto J, Esterbauer H, Tatzber F, Salonen R (1995) Intake of mercury from fish, lipid peroxidation, and the risk of myocardial infarction and coronary, cardiovascular, and any death in Eastern Finnish men. Circulation 91(3):645-655.
(SCOEL) Scientific Committee on Occupational Exposure Limits (2007) Recommendation from the Scientific Committee on Occupational Exposure Limits for elemental mercury and inorganic divalent mercury compounds. European Commission, SCOEL/SUM/84.
(U.S. EPA) U.S. Environmental Protection Agency (2001) Methylmercury (MeHg); CASRN 22967-92-6: Chemical Assessment Summary. National Center for Environmental Assessment, Integrated Risk Information System (IRIS), Washington, DC.
Virtanen JK, Rissanen TH, Voutilainen S, Tuomainen TM (2007) Mercury as a risk factor for cardiovascular diseases. J Nutr Biochem 18(2):75-85.
WHO and UNEP DTIE Chemicals Branch (2008) Guidance for identifying populations at risk from mercury exposure. Inter-organization Programme for the Sound Management of Chemicals, Geneva, Switzerland.
Azevedo BF, Furieri LB, Pecanha FM, Wiggers GA, Vassallo PF, Simoes MR, Fiorim J, de Batista PR, Fioresi M, Rossoni L, Stefanon I, Alonso MJ, Salaices M, Vassallo DV (2012) Toxic Effects ofMercury on the Cardiovascular and Central Nervous Systems. J Biomed Biotechnol 2012: 949048.
Branco V, Caito S, Farina M, Teixeira da Rocha J, Aschner M, Carvalho C (2017) Biomarkers of mercury toxicity: Past, present, and future trends. J Toxicol Environ Health B Crit Rev 20(3):119-154.
Clarkson TW and Magos L (2006) The toxicology of mercury and its chemical compounds. Crit Rev Toxicol 36: 609–662.
Hong Y-S, Kim Y-M, Lee K-E (2012) Methylmercury Exposure and Health Effects. J Prev Med Public Health 45:353-363.
National Research Council (US) Committee on the Toxicological Effects of Methylmercury (2000) Toxicological Effects of Methylmercury: 5, Health Effects of Metylmercury. National Academies Press, Washington, DC.
Salonen JT, Seppänen K, Nyyssönen K, Korpela H, Kauhanen J, Kantola M, Tuomilehto J, Esterbauer H, Tatzber F, Salonen R (1995) Intake of mercury from fish, lipid peroxidation, and the risk of myocardial infarction and coronary, cardiovascular, and any death in Eastern Finnish men. Circulation 91(3):645-655.
(SCOEL) Scientific Committee on Occupational Exposure Limits (2007) Recommendation from the Scientific Committee on Occupational Exposure Limits for elemental mercury and inorganic divalent mercury compounds. European Commission, SCOEL/SUM/84.
(U.S. EPA) U.S. Environmental Protection Agency (2001) Methylmercury (MeHg); CASRN 22967-92-6: Chemical Assessment Summary. National Center for Environmental Assessment, Integrated Risk Information System (IRIS), Washington, DC.
Virtanen JK, Rissanen TH, Voutilainen S, Tuomainen TM (2007) Mercury as a risk factor for cardiovascular diseases. J Nutr Biochem 18(2):75-85.
WHO and UNEP DTIE Chemicals Branch (2008) Guidance for identifying populations at risk from mercury exposure. Inter-organization Programme for the Sound Management of Chemicals, Geneva, Switzerland.