Event

The Department of Earth & Environmental Science

University of Pennsylvania

Invites you to attend a EES Seminar Series

Friday, October 4, 2024 - 3:00 PM

"Artisanal and Small-scale Gold Mining in the Peruvian Amazon: Mobilization, Bioaccumulation and Exposure of Mercury"

Artisanal and small-scale gold mining (ASGM) is a type of mining performed by individuals (often illegally) who utilize liquid elemental mercury to amalgamate and purify gold from surface soil deposits. This practice occurs in more than 70 nations and annually emits over 2000 tons of mercury (Hg) to the atmosphere. Local communities and ecosystems near ASGM experience chronic exposure to toxic Hg compounds as well as irreversible changes to the landscape. This presentation synthesizes recent and ongoing research to study the consequences of ASGM in the Amazon region of Madre de Dios, Peru.

Our team studied the distribution of mercury in the region, bioaccumulation of the metal toxin in aquatic and terrestrial species, and exposures of mercury to local populations. Some key insights of this work include the following: (1) Contrary to the common assumption that residents of ASGM communities experience the highest exposures, Hg from ASGM travels hundreds of kilometers from point sources and impact fisheries for communities that are not directly engaged in mining activity; (2) Hg emitted from ASGM activity is accumulating in old growth (primary) forests in the region, meaning that deforestation of these areas may release more mercury to local waterways compared to non-impacted deforested areas; (3) Because indigenous populations often rely on fish protein from local sources, these communities encounter the highest mercury exposures, experience the worst health outcomes, and have the lowest ability to prevent these impacts; (4) Other dietary exposures to metal toxins such as lead can occur in the region, suggesting the need to consider multiplicative health consequences of low level joint chemical exposures. Together, these insights highlight the cross-cutting impacts of broad landscape change, chemical exposures, and socio-economic vulnerability for populations near ASGM.

Dr. Heileen (Helen) Hsu-Kim

Professor of Environmental Engineering

Duke University

Heileen (Helen) Hsu-Kim is a Professor of Environmental Engineering at Duke University, where she has been a member of the faculty since 2005. Prior to joining Duke, Dr. Hsu-Kim completed her B.S. degree in Environmental Engineering at MIT, and M.S./Ph.D. degrees in Environmental Engineering at UC-Berkeley. Dr. Hsu-Kim’s expertise area is aquatic geochemistry and her research focuses on trace metals and metalloids in the environment. In addition to her research on mercury biogeochemistry, Dr. Hsu-Kim studies the environmental impacts of coal ash wastes, the recovery of rare earth elements and other critical metals from geological waste residuals, and methods to quantify personal exposures to metals such as lead in the ambient environment. Dr. Hsu-Kim is also the Director of Graduate Studies for Civil & Environmental Engineering at Duke and is currently an Associate Editor for Environmental Science & Technology.