Mercury Pollution - Similarities and Differences Between China and

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1 Mercury Pollution - Similarities and Differences Between China and Norway Xinbin Feng a and Thorjorn Larssen b a Institute of Geochemistry, CAS b Norwegian Water Research Institute (NIVA)

2 Mercury is a Global Pollutant Mercury is the only metal that occurs in the atmosphere mainly as gas phase Fish in pristine lakes in remote areas in North America and Europe contained high levels of MeHg concentrations Long range transport of mercury in the atmosphere followed by deposition of Hg to aquatic systems caused the elevation of MeHg in fish in this lakes

3 Anthropogenic Hg emissions to air Chapter 6, Fig. 6.4 Source: AMAP Norway

4 Pirrone and Mason, 2009

5 Source contributions to total Hg emissions in China, (Wu et al., 2006).

6 Primary man-made Hg emissions are growing fast in recent years due to rapid economic growth ( Wu et al., Environ. Sci. Technol., 2007) 1200 ertainty als) r) with unce nce interva ssions (t/yr 5% confiden Hg emis ( Uncertainty is still quite high, but diminishing over time (±78% in 1995; ±44% in 2003)

7 Changbai Mountain Waliguan GAW station Gongga Mountain Guiyang Leigong Mountain

8 Average TGM: 8.40 ng m -3 TGM in air(ng g/m 3 ) Sampling Date High temporal resolved TGM data in ambient air in Guiyang (Feng et al., JGR,2004)

9 14 TGM(per hour) Gongga 3.98±1.91 ngm -3 Changbai 3.22 ± 1.78 ng m -3 TGM(ng.m -3 ) Leigong Waliguan Fu et al., AE, 2008; Wan et al., ER, 2008; Fu et al., ACP, 2009

10 2 1 Gongga Mountain Changbai Leigong g Wujiang basin 4 3 Hg deposition fluxes at different regions in China with comparison to Europe and North hamerica 40 1 ) (ug m -2 a Hg deposit tion flux (

11 Wild fish samples were collected from 6 large reservoirs in Guizhou, China

12 Hg is fish from reservoirs in Guizhou Yan et al., 2009 (in revision)

13 Fish farming activities resulted in eutrophication of reservoir may aslo accelerate Hg methylation processes in reservoirs, therefore there is a potential MeHg pollution problem in fish in reservoirs in Guizhou. MeHg balance of six reservoirs in Wujiang River Reservoir TtlI Total Input TtlOt Total Outputt MH MeHg production Rti Ratio Age (g/y) (g/y) (g/y) (%) SFY YZD HJD PD DF WJD

14 Distribution of MeHg in water and sediment pore water Water(m m) Sedi iment(cm m) MeHg(ng/L) 界面水 WJD Water(m m) Sedi iment(cm m) Feng et al., Environmental Pollution, 2009 MeHg(ng/L) 界面水 DF200407

15 Norwegian Hg emissions in 2005 (approx 90% reduction ) Private households 11 % Other businesses 16 % Energy sectors 5% Smelting and mining 36 % Sum: approx 700 kg Transport 21 % Other industry 11 %

16 Norway has no coal fired power plants Focus on other sources: Metal smelting g( (Fe, Zn, Mn) Other industries Dental amalgam

17 Historically large local discharges (and emissions) E.g. Zn-smelter in Odda Historically large discharges, still severe impacts Currently low discharge and emissions And they still produce Zn, and make money!

18 Hg in 300 g trout

19 Any time trends? European emissions?

20 Any time trends? European emissions? Air concentrations? 2.2 Hg in air m -3 ng m Lista Birkenes Ny Ålesund From Aas et al., 2009 Annual report from NILU/SFT

21 Any time trends? European emissions? Air concentrations? Deposition? From Wängberg et al., Atmos. Environ.

22 Hg in perch From Fjeld et al., in prep. Comparison of Hg in perch between samples collected in 1991 and 2008

23 Total Mercury Exposure Methyl-mercury Exposure

24 Summary High and increasing Hg emissions and deposition in China; while low and decreasing Hg emission and deposition in Norway High and increasing Hg in fish in Norway and low but would-be increasing i Hg in fish hin China Many of the least known processes are the same both places Catchment based biogeochemical processes impacted by climate changes? Increased Hg methylation in aquatic systems with increase of temperature? Food web changes resulted from climate change? A comparison study would be useful to understand the increased rate of MeHg bioaccumulation in food chain, including links to climate change.