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Title: Artificial lake expansion amplifies mercury pollution from gold mining
Artisanal and small-scale gold mining (ASGM) is the largest global source of anthropogenic mercury emissions. However, little is known about how effectively mercury released from ASGM is converted into the bioavailable form of methylmercury in ASGM-altered landscapes. Through examination of ASGM-impacted river basins in Peru, we show that lake area in heavily mined watersheds has increased by 670% between 1985 and 2018 and that lakes in this area convert mercury into methylmercury at net rates five to seven times greater than rivers. These results suggest that synergistic increases in lake area and mercury loading associated with ASGM are substantially increasing exposure risk for people and wildlife. Similarly, marked increases in lake area in other ASGM hot spots suggest that “hydroscape” (hydrological landscape) alteration is an important and previously unrecognized component of mercury risk from ASGM.  more » « less
Award ID(s):
1806983
NSF-PAR ID:
10233122
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
48
ISSN:
2375-2548
Page Range / eLocation ID:
eabd4953
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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