12/4/2015. Chris Moore 12/7/2015.

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1 Chris Moore 12/7/

2 Today s Discussion Background Compartments Atmosphere Arctic Anthropogenic inputs Soil Freshwater/wetlands Ocean Mercury (Hg) Hydrargyrum (Hg) 66 th most abundant element in Earth s crust Found largely in the ore cinnabar 2

3 From: Trace Elements In Terrestrial Environments (2001) Species of Hg Elemental: Hg 0 Oxidized Hg (2+ or 1+): gases/particles Inorganic Hg: HgCl 2 HgO, Hg(NO 3 ) 2 Organic Hg: CH 3 Hg, (CH 3 ) 2 Hg Environment Atmosphere Water Soil Species Elemental, oxidized Hg Oxidized Hg Elemental, Oxidized Hg 3

4 Mercury Why do we care? Mercury cycle converts inorganic forms (mercury metal) to organic forms (methylemercury) Inorganic mercury in high doses is toxic Methylmercury is a neurotoxic pollutant in very low doses Acute mercury poisoning is called Minamata Disease Methylmercury bioaccumulates and bioconcentrates upward through the food chain Adverse Health Effects of Hg Nervous system, renal, cardiovascular effects, cancer, genotoxity, reproductive and developmental effects, gastrointestinal (digestive system) and hepatic (liver) effects, effects on the skin,, effects on the immune system, effects on the thyroid gland. Minamata Disease Victims: 12,615 Deaths: 1,

5 Global Hg Cycle Selin et al., 2009, copyright 2007 National Academy of Sciences, U.S.A. Global Hg Cycle 2013 UNEP 5

6 Hg Bioaccumulation methylmercury in lake water:1 microorganisms 10 5 for macroorganisms 10 6 fish, birds and humans are Hg in Different Compartments Preindustrial Modern Lindberg et al., 2007 copyright, American Geophysical Union 6

7 Hg content in Wyoming ice core Hg emission sources UNEP, 2013 Atmospheric Mercury 7

8 Hg in the atmosphere Mercury has a significant atmospheric component Can be transported 1000s of km Transport leads to contamination far from point sources of pollution via wet and dry deposition Atmospheric chemistry plays an important role in dry deposition Once transported the landscape takes over converting inorganic to organic Hg in the Atmosphere Corbitt et al Environmental Science and Technology 8

9 Mercury in the Arctic Mercury in the Arctic Arctic ecosystems are fragile Methyl mercury form is a neurotoxin and accumulates in living organisms Piscivorous fish Polar Bears Whales Seals Indigenous Arctic peoples diet heavily reliant on these organisms Valera et al NeuroToxicology; Tian et al Environment International 9

10 Mercury in the Arctic Metal Ions in Biological Systems (2005) Mercury and Ozone in the Arctic Surface Layer From Steffen et al ACP 10

11 Alert, Nunavut, Canada Atmospheric monitoring in the Arctic From Steffen et al STOTEN 11

12 Barrow, Alaska Mercury and Ozone Consolidated Ice = Depletion Open Lead = Instant recovery Adapted from Moore et al Nature 12

13 Sea Ice Leads Barrow March 23, 24, 25, 26, 2012 Large cracks in the sea ice Can last a few hours to a few days Can be a few meters to 1000s of kilometers in extent Caused by changes in wind and sea currents Immediate large heat flux from the water that can be up to 40 o C warmer than the air 192km Anthropogenic Influences on the Hg Biogeochemical Cycle 13

14 Hg as a commodity Anthropogenic Sources 2013 UNEP 14

15 Quicksilver Historic Activities Mercury has been mined for over 3500 years Cinnabar yields vermillion (red dye) used in crafts for thousands of years Largely mined in South America by both the Roman Empire and Spanish colonists Life expectancy was under two years for miners China s first emperor 15

16 Global anthropogenic Hg emission map, 2010 UNEP 2013 Temporal variation of Hg anthropogenic emissions UNEP

17 Minamata Convention on Mercury Products Hg contained production, export and import will be banned by Artisanal and Small-Scale Gold Mining Countries need to draw up strategies to reduce the amount of mercury used by smallscale miners Power Stations to Cement Factories The new treaty will control mercury emissions and releases from various large industrial facilities Minamata Convention 128 signatures, 19 ratifications 17

18 Mercury in Soils Mercury in Soils 18

19 Gaseous Mercury in Soils Obrist et al ES&T Hg Emissions from Soils From: Agnan et al ES&T in press 19

20 Hg Emissions from Soils From: Agnan et al ES&T in press Hg Emissions from Soils From: Agnan et al ES&T in press 20

21 Hg in Freshwater Systems Hg in Freshwater Systems Metal Ions in Biological Systems (2005) 21

22 Hg in Freshwater Systems Hg aqueous reactions - Everglades 22

23 Hg species in water From: Trace Elements In Terrestrial Environments (2001) Hg in the Oceans 23

24 Hg in the Oceans 24