Mercury is a potent neurotoxin that has deletorious impacts on humans and wildlife [Driscoll et al, 2013]. Mercury is particularly dangerous in two forms: (1) the inhalation of elemental mercury vapors and (2) the ingestion of methylmercury from food sources.
In humans, acute exposure can lead to a metallic taste, tremors, lack of coordination, and visual and hearing impairment, amongst other symptoms [Rhea et al, 2013]. Chronic exposure can lead to reduced cognitive development, deformities, and even death. These symptoms are particularly pronounced when exposure occurs in developing fetuses and children. In animals, exposure to mercury can lead to reduced survivorship, lack of care for young, reduced viability of eggs, and neurologic impairment.
The extent of mercury contamination in Madre de Dios has been examined in several studies focusing on both human health and the environment. These studies have found high methylmercury exposure in mining communities [Ashe, 2012] and in fish 200 km downstream of ASGM sites [Diringer et al., 2015]. Hair mercury concentrations in children and women of child-bearing age far exceed levels known to impact nervous system development [Wyatt et al., 2014]. Human Hg concentrations in Madre de Dios have reached such high levels that in May 2016, the Peruvian government declared a public health emergency with an estimated 48,000 people exposed to high Hg [Fraser, 2016]. These high Hg concentrations are not limited to people; giant river otters (an endangered local species) have also been found to have elevated mercury levels [Gutleb et al., 1997].
In humans, acute exposure can lead to a metallic taste, tremors, lack of coordination, and visual and hearing impairment, amongst other symptoms [Rhea et al, 2013]. Chronic exposure can lead to reduced cognitive development, deformities, and even death. These symptoms are particularly pronounced when exposure occurs in developing fetuses and children. In animals, exposure to mercury can lead to reduced survivorship, lack of care for young, reduced viability of eggs, and neurologic impairment.
The extent of mercury contamination in Madre de Dios has been examined in several studies focusing on both human health and the environment. These studies have found high methylmercury exposure in mining communities [Ashe, 2012] and in fish 200 km downstream of ASGM sites [Diringer et al., 2015]. Hair mercury concentrations in children and women of child-bearing age far exceed levels known to impact nervous system development [Wyatt et al., 2014]. Human Hg concentrations in Madre de Dios have reached such high levels that in May 2016, the Peruvian government declared a public health emergency with an estimated 48,000 people exposed to high Hg [Fraser, 2016]. These high Hg concentrations are not limited to people; giant river otters (an endangered local species) have also been found to have elevated mercury levels [Gutleb et al., 1997].