Human influence on the global mercury cycle: understanding the past and projecting the future

• Published in: E3S web of conferences Vol. 1; p. 30001
• Main Authors: Amos, H. M., Jacob, D. J., Streets, D. G., Sunderland, E. M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Les Ulis EDP Sciences 01-01-2013
• Subjects: anthropogenic enrichment; Anthropogenic factors; Atmospheric pollution deposition; biogeochemical box model; Computer simulation; Cycles; Emissions; Enrichment; Global health; Human influences; legacy mercury; Marine ecosystems; Mercury; Mercury (metal); Reservoirs; Terrestrial environments; Toxicity
• ISSN: 2267-1242; 2555-0403; 2267-1242
• DOI: 10.1051/e3sconf/20130130001

Humans have been releasing mercury (Hg) to the environment since antiquity. Due to the toxicity of Hg, the extent of anthropogenic enrichment is a global health concern. Here we use a global biogeochemical box model to quantify anthropogenic enrichment, investigate the timescales required to remove anthropogenic Hg from actively cycling reservoirs, and explore future anthropogenic emission scenarios and their impact on Hg accumulation. By considering the full history of anthropogenic emissions, we find that the global ocean has been substantially enriched by human activity, with implications for exposures of marine fish. Model simulations show anthropogenic Hg entering surface reservoirs is removed on the order of years. Future emission scenarios that achieve substantial reductions in global anthropogenic Hg emissions have the dual benefit of decreasing atmospheric deposition and decreasing the pool of legacy Hg actively cycling in terrestrial and oceanic ecosystems.