Kvikksølv– fortsatt et miljøproblem?

Eirik Fjeld, Norsk institutt for vannforskning – NIVA foredrag ved Teknologidagene

6. okt 2014

Quiz Fire historier og et blikk på vei

Quiz

Antikk astronomiI antikken ble de syv kjente metallene gull, sølv, jern, bly, tinn, kopper og kvikksølv knyttet til de syv kjente klassiske planetene.

Hvilken planet ble kvikksølv knyttet til?

Kjemisk symbolKvikksølv har det kjemiske symbolet Hg.Det er avledet fra den gammelgreske betegnelsen:

• Heptageniidae: Det syvende metall

• Hygrargyrum: Flytende sølv

• Hermesgyridum: Hermes’ hav

Sinober, IKvikksølv i naturen finnes hovedsakelig i mineralet sinober. Den kjemiske sammen-setningen av sinober er:

• Hg3S

2Cl

• HgS

• Hg4(Br,Cl)

2O

Sinober, III Nordmarka ved Oslo finnes turisthytta Sinober. Den har fått navnet sitt fordi:

• Det ble drevet gruver med bl.a. uttak av sinober i nærheten

• Hytta ble opprinnelig malt i en sinober-rød maling

• På 1800-tallet flyttet en husmann ved navn Zinoberrud dit fra Nannestad

Hg i atmosfærenKvikksølvkonsentrasjonen (gassfase) i luft ved NILUs målestasjon på Zeppelinfjellet på Svalbard var i 2012 i snitt 1,5 ng/m3. Hva var middelkonsentrasjonen ved Birkenes på Sørlandet?

• 18,5 ng/m3

• 9,0 ng/m3

• 1,6 ng/m3

Kvikksølvdeponeringer til nedbørfelt

De årlige avsetningene av kvikksølv til et nedbørfelt i sørøst-Norge ble i 2005 beregnet til å være:

• 9,4 g/km2

• 70 g/km2

• 215 g/km2

Kvikksølv lagret i et nedbørfelt

Kvikksølv lagret i jordsmonnet i samme nedbørfelt ble beregnet til å være:

• 75,0 kg/km2

• 18,3 kg/km2

• 4,8 kg/km2

Kvikksølv og grenseverdier i vann

I Mjøsa har storørreten over 2,5 kg en midlere konsentrasjon av kvikksølv som overskrider grenseverdien som EU har satt for salg til konsum (0,5 mg/kg).

EU har i vanndirektivet bestemt at Hg-konsentrasjonen i ferskvann i gjennomsnitt ikke skal overskride 50 ng/L for å oppfylle EQS-kravet (Environmental Quality Standard).

Hvor høy tror du Hg-konsentrasjonen i vann fra Mjøsa er?

Kvikksølv lagret i atmosfæren

Dersom alt kvikksølvet i atmosfæren samles opp, hvor mange olympiske svømmebasseng vil det fylle?

Historie 1Kretsløp og kilder

Global kvikksølvsyklus

Menneskeskapte kilder til luft i 2010

37%

24%

10%

9%

5%

5%

4%2%1%2%

Source Artisanal and small-scale gold mining

Coal burning (all uses)

Primary production of nonferrous metals (Al, Cu, Pb, Zn)

Cement production

Large-scale gold production

Consumer product waste

Contaminated sites

Primary production of ferrous metals

Chlor-alkali industry

Other

data fra UNEP 2013

Trend i utslipp til luft, vann og jord

Hg over time. Emissions to air peak in 1970, mainly due topaint volatilization and incineration of batteries. Although Hguse in batteries increased from 1970 to 1980, open-air wasteburning at landfills was eliminated in developed countries likethe US during this period following solid waste regulations.69,70

Use of explosives and weapons was a major emitter to airduring 1900−1950 with a peak in WWII.Water releases also exhibit a peak during WWII, due to

laboratory uses and chemicals manufacturing. The overallmaximum occurs in 1960, with a steep subsequent declinefollowing implementation of chlor-alkali liquid effluentregulations in the early 1970s in North America andEurope.71,72 Implementation of wastewater treatment fromthe 1980s onward led to even greater declines in waterreleases73 but contributes a small amount to soils due to

application of Hg-containing sludges.16,56 Similarly, chlor-alkaliplants began capturing Hg in sludges in the 1970s, which weresubsequently dumped on land or landfilled on-site.72 The 1970peak in soil releases is driven by Hg used in chlor-alkali plantsand Hg-containing pesticides and fertilizer that were applieddirectly to land.

Implications for the Biogeochemical Hg Cycle andAtmospheric Trends. Figure 6 shows simulated atmosphericHg from 1850 to the present after adding our historicalinventory of commercial Hg emissions and releases to theglobal biogeochemical Hg model described previously. FigureS3, Supporting Information, gives present-day reservoirs andflows. Our simulated present-day atmospheric reservoir is 5800Mg; the mean Hg concentration in the upper ocean is 1.5 pM,and the AEF for atmospheric deposition is 4.4. The originalAmos et al.4 simulation not including commercial Hg yielded apresent-day atmosphere of 5300 Mg but did not account forburial of Hg in ocean margin sediments.57 Accounting for burialwithout commercial Hg results in an atmosphere that is too low(2700 Mg). Conversely, including commercial Hg in theoriginal Amos et al.4 simulation without burial of riverine Hgwould yield a present-day atmospheric reservoir of 10 000 Mg,much higher than that observed.Our simulated present-day atmospheric reservoir of 5800 Mg

is slightly higher than the observational range (4600−5600Mg), but this could be accommodated by uncertainty in Hg re-emission from soils.74,75 The atmospheric increase over the pastdecade (Figure 6) is driven by rising anthropogenic emissionsin the Streets et al.12 inventory (primarily from coal burning inAsia) and rising releases from ASGM22 (Figures 3 and 4).However, Wilson et al.20 and AMAP/UNEP22 suggest thatglobal total anthropogenic emissions have in fact remainedconstant since 2000. AMAP/UNEP estimate that coalcombustion emissions specifically have remained constantsince at least 2005, as increased energy production efficiency

Figure 3. Global historical Hg consumption in commercial products.Consumption is partitioned for each decade between the different usecategories of Table 1 and further partitioned between developedcountries and developing countries after 1970.

Figure 4. Historical global releases of Hg to the environment. TheStreets et al.12 inventory includes atmospheric releases fromcombustion, smelting, mining, and chlor-alkali plants. Additional air,soil, water, and landfill releases shown are associated with commercialHg products as quantified in this work.

Environmental Science & Technology Article

dx.doi.org/10.1021/es501337j | Environ. Sci. Technol. 2014, 48, 10242−1025010246

Hg over time. Emissions to air peak in 1970, mainly due topaint volatilization and incineration of batteries. Although Hguse in batteries increased from 1970 to 1980, open-air wasteburning at landfills was eliminated in developed countries likethe US during this period following solid waste regulations.69,70

Use of explosives and weapons was a major emitter to airduring 1900−1950 with a peak in WWII.Water releases also exhibit a peak during WWII, due to

laboratory uses and chemicals manufacturing. The overallmaximum occurs in 1960, with a steep subsequent declinefollowing implementation of chlor-alkali liquid effluentregulations in the early 1970s in North America andEurope.71,72 Implementation of wastewater treatment fromthe 1980s onward led to even greater declines in waterreleases73 but contributes a small amount to soils due to

application of Hg-containing sludges.16,56 Similarly, chlor-alkaliplants began capturing Hg in sludges in the 1970s, which weresubsequently dumped on land or landfilled on-site.72 The 1970peak in soil releases is driven by Hg used in chlor-alkali plantsand Hg-containing pesticides and fertilizer that were applieddirectly to land.

Implications for the Biogeochemical Hg Cycle andAtmospheric Trends. Figure 6 shows simulated atmosphericHg from 1850 to the present after adding our historicalinventory of commercial Hg emissions and releases to theglobal biogeochemical Hg model described previously. FigureS3, Supporting Information, gives present-day reservoirs andflows. Our simulated present-day atmospheric reservoir is 5800Mg; the mean Hg concentration in the upper ocean is 1.5 pM,and the AEF for atmospheric deposition is 4.4. The originalAmos et al.4 simulation not including commercial Hg yielded apresent-day atmosphere of 5300 Mg but did not account forburial of Hg in ocean margin sediments.57 Accounting for burialwithout commercial Hg results in an atmosphere that is too low(2700 Mg). Conversely, including commercial Hg in theoriginal Amos et al.4 simulation without burial of riverine Hgwould yield a present-day atmospheric reservoir of 10 000 Mg,much higher than that observed.Our simulated present-day atmospheric reservoir of 5800 Mg

is slightly higher than the observational range (4600−5600Mg), but this could be accommodated by uncertainty in Hg re-emission from soils.74,75 The atmospheric increase over the pastdecade (Figure 6) is driven by rising anthropogenic emissionsin the Streets et al.12 inventory (primarily from coal burning inAsia) and rising releases from ASGM22 (Figures 3 and 4).However, Wilson et al.20 and AMAP/UNEP22 suggest thatglobal total anthropogenic emissions have in fact remainedconstant since 2000. AMAP/UNEP estimate that coalcombustion emissions specifically have remained constantsince at least 2005, as increased energy production efficiency

Figure 3. Global historical Hg consumption in commercial products.Consumption is partitioned for each decade between the different usecategories of Table 1 and further partitioned between developedcountries and developing countries after 1970.

Figure 4. Historical global releases of Hg to the environment. TheStreets et al.12 inventory includes atmospheric releases fromcombustion, smelting, mining, and chlor-alkali plants. Additional air,soil, water, and landfill releases shown are associated with commercialHg products as quantified in this work.

Environmental Science & Technology Article

dx.doi.org/10.1021/es501337j | Environ. Sci. Technol. 2014, 48, 10242−1025010246

Hg over time. Emissions to air peak in 1970, mainly due topaint volatilization and incineration of batteries. Although Hguse in batteries increased from 1970 to 1980, open-air wasteburning at landfills was eliminated in developed countries likethe US during this period following solid waste regulations.69,70

Use of explosives and weapons was a major emitter to airduring 1900−1950 with a peak in WWII.Water releases also exhibit a peak during WWII, due to

laboratory uses and chemicals manufacturing. The overallmaximum occurs in 1960, with a steep subsequent declinefollowing implementation of chlor-alkali liquid effluentregulations in the early 1970s in North America andEurope.71,72 Implementation of wastewater treatment fromthe 1980s onward led to even greater declines in waterreleases73 but contributes a small amount to soils due to

application of Hg-containing sludges.16,56 Similarly, chlor-alkaliplants began capturing Hg in sludges in the 1970s, which weresubsequently dumped on land or landfilled on-site.72 The 1970peak in soil releases is driven by Hg used in chlor-alkali plantsand Hg-containing pesticides and fertilizer that were applieddirectly to land.

Implications for the Biogeochemical Hg Cycle andAtmospheric Trends. Figure 6 shows simulated atmosphericHg from 1850 to the present after adding our historicalinventory of commercial Hg emissions and releases to theglobal biogeochemical Hg model described previously. FigureS3, Supporting Information, gives present-day reservoirs andflows. Our simulated present-day atmospheric reservoir is 5800Mg; the mean Hg concentration in the upper ocean is 1.5 pM,and the AEF for atmospheric deposition is 4.4. The originalAmos et al.4 simulation not including commercial Hg yielded apresent-day atmosphere of 5300 Mg but did not account forburial of Hg in ocean margin sediments.57 Accounting for burialwithout commercial Hg results in an atmosphere that is too low(2700 Mg). Conversely, including commercial Hg in theoriginal Amos et al.4 simulation without burial of riverine Hgwould yield a present-day atmospheric reservoir of 10 000 Mg,much higher than that observed.Our simulated present-day atmospheric reservoir of 5800 Mg

is slightly higher than the observational range (4600−5600Mg), but this could be accommodated by uncertainty in Hg re-emission from soils.74,75 The atmospheric increase over the pastdecade (Figure 6) is driven by rising anthropogenic emissionsin the Streets et al.12 inventory (primarily from coal burning inAsia) and rising releases from ASGM22 (Figures 3 and 4).However, Wilson et al.20 and AMAP/UNEP22 suggest thatglobal total anthropogenic emissions have in fact remainedconstant since 2000. AMAP/UNEP estimate that coalcombustion emissions specifically have remained constantsince at least 2005, as increased energy production efficiency

Figure 3. Global historical Hg consumption in commercial products.Consumption is partitioned for each decade between the different usecategories of Table 1 and further partitioned between developedcountries and developing countries after 1970.

Figure 4. Historical global releases of Hg to the environment. TheStreets et al.12 inventory includes atmospheric releases fromcombustion, smelting, mining, and chlor-alkali plants. Additional air,soil, water, and landfill releases shown are associated with commercialHg products as quantified in this work.

Environmental Science & Technology Article

dx.doi.org/10.1021/es501337j | Environ. Sci. Technol. 2014, 48, 10242−1025010246

Horowitz et al. 2014

Norske utslipp til luftKg

/år

0

150

300

450

600

750

900

1995 1997 1999 2001 2003 2005 2007 2009 2011

Olje- og gassutvinningIndustri og bergverkEnergiforsyningOppvarming i andre næringer og husholdningerVeitrafikkLuftfart, sjøfart, fiske, motorredskaper m.m.Andre kilder

Kilde, SSB

Kvikksølv til et nedbørfelt i Syd-Sverige,nedbørfeltareal: 10 km2, innsjøareal 1 km2

Etter Lindqust et al. 1991

Kvikksølv i en sedimentkjerne fra Mensvatn, Porsgrunn. Nivåene reflekterer atmosfæriske avsetninger.

Historie 2The Joker – metylkvikksølv

Hg - tilstandsformerElementært kvikksølv: Hg(0) flyktig – fordamper, minst giftige form

Ionisk kvikksølv: Hg (II) og Hg (I)vannløselig, binder seg til sedimenter og organisk materiale, giftig

Organisk kvikksølv: Metylkvikksølv (MeHg+, CH3Hg+)

dannes av bakterier i oksygenfritt miljø i vann, sedimenter og fuktig jord, akkumuleres i næringskjeder, vanlig form i fisk, meget giftig

Hg - tilstandsformer

Hg-sulphides

Metyl-Hg katastofale hendelser

Minamata-bukta,Chisso Corp 1951-1968

Irak, kvikksølvbeisetsåkorn,1971-1972

MeHg-forgiftning i det små

http://www.youtube.com/watch?v=e2Nsy0c22R8

En sushi-elskers bekjennleser Richard Gelfond, CEO for IMAX:

http://www.consumerreports.org/cro/magazine/2014/10/sick-from-sushi/index.htm

Hva med fisken selv?Hg-konsentrasjoner i føden og effekter

> 2,5 µg/g: Redusert vekst

> 0,5 µg/g: Påvirker atferd< 0,2 µg/g: Påvirker reproduksjon

Økt dødelighet

Depew et al 2012. Mercury toxicity to fish: A review.

Historie 3Fra La Grande River til Gårdsjön — hva en oppdemming kan gjøre

La River Grande – Chisasabi

James Bay Cree-folkets hjemland "James Bay Project (Hydro-Quebec), blant verdens største vannkraftutbygginger "Omlag 11 000 km2 av nedbørfeltet med barskog, taiga, ble neddemt

Oppdemming og kvikksølv• Oppdemming frigjør kvikksølv og organisk

materiale lagret i nedbørfeltene til det akvatiske miljøet

• Dette stimulerer den biologiske metyleringen av kvikksølv og konsentrasjonene i fisk øker dramatisk

• Førte til at Cree-befolkningen og Inuittene måtte begrense sitt tradisjonelle fiske. Cree-folket i området har nå de høyeste Hg-konsentrasjonene i blod blant Canadas First Nation folkegrupper.

Hg i gjedde La Grande Complex

Executive Summary La Grande Complex Environmental Monitoring at the La Grande Complex

Evolution of Mercury Levels in Fish Summary Report 1978-2012

5

Figure 1: Temporal Evolution of Mean Mercury Levels in Standardized-Length fish in Main La Grande Complex Reservoirs

3.4 Diversion Routes The main lessons derived from the monitoring of mercury levels in standardized-length fish caught along the Laforge and Eastmain-Opinaca-La Grande diver-sion routes are the following: x The evolution of fish mercury levels recorded

along diversion routes confirms that mercury is exported from reservoirs and transferred to fish living downstream;

x In some waterbodies along these flow routes, mercury levels may be higher than those in the reservoir providing the inter-basin transfer, because of the combined effect of mercury export downstream from the reservoir and additional mercury production from the local flooding of terrestrial environments;

Gårdsjön –en traktorvei i vellinga

• Studieområde for sur nedbør og kvikksølvomsetning i et nedbørfelt, nær Göteborg

• Traktorvei, kjøreskader og minsket drenering i et kontroll-område i 1999

• MeHg-avrenningen fra det berørte delnedbørfeltet økte umiddelbart

Gårdsjön, MeHg-avrenning614 J. MUNTHE AND H. HULTBERG

Figure 5. Annual transport of MeHg from reference catchment F1 (filled bars) and experimentalcatchment G1 (open bars).

and a temporary logging road was constructed (soil, branches, etc. were used tostabilise the road). The temporary road blocked the water flow in the small streamin the center of the catchment and led to the formation of a small dam (< 50 m2)upstream. The blockage was removed immediately after discovery and the streamflow returned to normal within a few weeks after the incident. However, the naturalsoil conditions were altered and the resulting change in water flow paths remained.

The temporary logging road led to sharp increases in the concentrations ofMeHg in runoff sampled at the catchment outlet some 100 m downstream (Fig-ure 2). In contrast to this, TotHg was fairly stable (Figure 1). In Figure 5 andFigure 6, the annual transport of MeHg and TotHg, respectively, for the period1993 to 2001 are presented.

The increase in MeHg transport is significant for 1999 (when the incident oc-cured) but also for 2000 and 2001. This indicates that a permanent damage to theforest soil and the water flowpaths has occurred. During the same period, a slightincrease in MeHg transport from the experimental catchment G1 also occurred. In1999 and 2000, TotHg fluxes in F1 also were considerably higher than previousyears. The reason for this is most likely that the years 1998, 1999 and 2000 wereunusually wet, with considerably higher runoff than the preceeding years. Duringthese years, runoff from reference area F1 was 748, 827 and 749 mm, respectively,whereas the average for the period of 1994 to 2001 was 547 mm. In Table III, theaverage annual fluxes for the period 1994 to 1998 are compared with the period1999 to 2001.

1993 1994 1995 1996 1997 1998 1999 2000 2001

250

200

50

Traktorvei, kjøreskader

Reference catchment, left bar"Experimental cathment, right bar

Historie 4En norsk fiskehistorie

Hg i abbor i Norge• Landsomfattende undersøkelse på begynnelsen av

1990-tallet viste tildels betydelige konsentrasjoner av Hg i fisk fra skogssjøer uten lokal forurensing

• Et sett innsjøer ble gjenfisket i 2008

Innsjøene21 innsjøer ble gjenfisket i 2008, av disse var 10 tidligere prøvetatt i 1991 (markert i rødt)

Skogsjøer, sure til nøytrale, hovedaskelig humuspåvirkede og næringsfattige (N og P), innsjøareal: 0,04–16 km2 (median: 0,8 km2), høyde over havet: 18-571 m(median 206 m).

Lengde-justerte konsentrasjoner

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8

2008

: Hg,

mg/

kg

Year X: Hg, mg/kg

1990

1991

1992

1998

1999

2000

2001

2002

Year X

1:1

Justert til midlere lengde: 20.2 cm (≈ 100 g)

Lengdejusterte gjennomsnitt,1991 vs.2008

Årsaker til økningen?Økningen av Hg i abbor (60 %) – på tross av reduserte atmosfæriske avsetninger – er trolig forårsaket av noen storskala miljømessige endringer

Klimaendringer – et våtere og varmere klima?

Reversering av forsuring – minsket sulfatdeponeringer, mindre surt vann og endringer i vannkjemi?

KlimaendringerVarmere og våtere klima kan

øke den mikrobiologisk aktive perioden i nedbærfeltene og stimulere metyleringen av Hg i jord og våtmarker

gi varmere oveflatevann (epilimnion) i innsjøer og mer stabil sjiktning og forårsake lengre oksygenfrie perioder og økt metylering

gi økt avrenning av humus og Hg, og forårsake en økt brunfarging av innsjøer, stimulere metyleringen og senke fotodemetyleringen

Redusert forsuring

Minskede sulfatdeponeringer og reversert forsuring kan

gi økt løselighet av humus i jord og øke avrenningen av Hg-humus komplekser fra nedbørfeltet

gi økt avrenning av humus og Hg, forårsake en økt brunfarging av innsjøer, stimulere metyleringen og senke fotodemetyleringen

Et blikk på veiKan trafikk og veibygging bety noe?

Veibygging og kvikksølv

• Avskjæring/oppdemming av vannveier – minsket drenering/vannutskiftning

• Anleggsvirksomhet, hugging av skog, bygging av vei –> endrede hydrologiske forhold, fuktigere grunn

• Deponering av rene masser med jord og vegetasjon i fuktig terreng

Økt metylering og avrenning av Hg og MeHg

Åkersvika natureservat- Hamar

E6 løper gjennom et våtmarksområde og utløpsområdet for Flagstadelva. "Veien sperrer stedvis for vannutskiftning og lager stagnante dammer. "Disse har potensiale for å være «hot spots» for metylering av Hg.

Åkersvika – stagnante dammer

Veisalting og Hg• Forholdet er lite studert

• Veisalting kan fremme avrenning av humusstoffer (salting bryter ned jordstrukturen) – som komplekserer Hg og MeHg

• Høye konsentrasjone av klorid kan bringe mer Hg og MeHg i løsning som kloridkomplekser -> økt mobilisering

• Økt salting kan skape tetthetsgradienteri innsjøer som hemmer vår- og høst-sirkulasjonen. Kan skape oksygenfrieforhold i bunnvannet som stimulerer MeHg-produksjonen

Oppsummering• Betydelige mengder kvikksølv ligger lagret i nedbørfeltene

• Mobilisering og metylering av dette kvikksølvet må unngås

• Endringer i et nedbørfelts hydrologi kan mobilisere kvikksølv og stimulere produksjonen av metylkvikksølv

• Tilførsel av organisk materiale til innsjøer og våtmarksområder kan øke produksjonen av metylkvikksølv

• Salting kan tenkes å mobilisere kvikksølv og Hg-humuskomplekser, samt skape anoksiske forhold i bunnvann som stimulerer metylering av kvikksølv