Effects of a century of mining and industrial production on metal contamination of a model saline ecosystem, Great Salt Lake, Utah

Abstract

Effects of mining and metals production have been reported in freshwater lake sediments from around the world but are rarely quantified in saline lake sediments, despite the importance of these lake ecosystems. Here we used dated sediment cores from Great Salt Lake, Utah, USA, a large saline lake adjacent to one of the world's largest copper mines, to measure historical changes in the deposition of 22 metals. Metal concentrations were low prior to the onset of mining in the catchment in 1860 CE. Concentrations of copper, lead, zinc, cadmium, mercury and other metals began increasing in the late 1800s, with peaks in the 1950s, concomitant with enhanced mining and smelting activities. Sedimentary metal concentrations in the 1950s were 20-40-fold above background levels for copper, lead, silver and molybdenum. Concentrations of most metals in surficial sediments have decreased 2-5-fold, reflecting: 1) storage and mineralization of sedimenting materials in a deep brine layer, reducing metal transport to the sediments; 2) improved pollution control technologies, and; 3) reduction in mining activity beginning in the 1970s and 1980s. Despite reductions, concentrations of many metals in surficial sediments remain above acceptable contamination thresholds for aquatic ecosystems with migratory birds, and consumption advisories for mercury have been placed on three waterfowl species. The research also highlights that metal deposition in saline lakes is complicated by effects of hypersaline brines and deep-water anoxia in regulating sediment redox and release of metals to surface waters. Given the importance of saline lakes to migratory birds, metals contamination from mining and metals production should be a focus of saline lake remediation.

A Literature Review of the Environmental and Health Risks of Copper Foil Manufacturing Plants in Relation to a New Facility Planned in Catalonia, Spain

“…With respect to the presence of copper in the environment, it is well known that the mining and production of this metal can mean various adverse impacts [14][15][16][17] . These impacts include-among others-water and soils pollution, and emissions of greenhouse gases [18][19][20][21][22][23] .…”

Halophilic nematodes live in America’s Dead Sea

“…S2L), which likely yields extensive ecological effects at multiple trophic levels (44). Samples collected from site 6 were particularly high in arsenic content, which can be attributed to that site's relative proximity to mining and smelting activities (45). Taken together, the GSL-nematode microbiome contains several members with known mechanisms of energy production, hypersaline tolerance, and toxic-chemical resistance.…”

Spatial enrichment assessment, source identification and health risks of potentially toxic elements in surface sediments, Central Asian countries

“…4 Regional differences of the EFs of metals in surface sediments across the CACs which is not only related to industrial and agricultural activities but has also been connected to the high background value for Zn in the region. Here we took core sediments from lake bottoms as background references in local regions (Lin et al 2016;Wurtsbaugh et al 2020;Yu et al 2021), and the average concentration of Zn in the CACs was up to 51.3 mg kg −1 (Table S4), which significantly exceeded the background level for sediments from around the world (9 mg kg −1 ) (Table S4). Moreover, studies have shown that Zn contents in rivers of mountainous regions are also relatively high (Groll et al 2015;Zhang et al 2020).…”