Lead and Copper Isotopes in Environmental Sciences€¦ · III.204Pb (1%) stable, non radiogenic ,...

Lead and Copper Isotopes in

Environmental

Sciences

Martin Mihaljevič Institute of Geochemistry, Mineralogy and Mineral resources

Faculty of Science, Charles University

IGCP/SIDA 594 Training course, University of the Witwatersrand, Johannesburg, July 13-15, 2013

• Metals are global contaminants

• Geochemical archives

• Pb and Cu isotopes

• Metodological approaches

• Practical applications

Introduction

Lead

Renberg et al. Holocene, 11, 511-516

Lead – global contaminant

Sweeden

Spain

Swiss

• Total concentration and mineralogical form is

not sufficient for evaluation of contamination

• Tracing of sources (local, global), kinetics of

processes, residence time are of great

concerns

• Convenient approach provides isotopic study

Introduction

I. Short lived radionuclides 210Pb (t1/2 = 22 years) 212Pb (t1/2 = 10 hours)

214Pb (t1/2 = 26.8 min)

II. Products of U and Th decay 206Pb, 207Pb a 208Pb

III. 204Pb (1%) stable, non radiogenic , primordial, constant

abundance on Earth in time

parent isotope Pb isotope decay half time

(years)

238U 206Pb (24%) 4,466 x 109

235U 207Pb (23%) 0,704 x 109

232Th 208Pb (52 %) 1,401 x 1010

Pb isotopes

210Pb cycle

210Pb is decay product

of 222Rn

Mihaljevič et al. (2006) Sci Tot Environ 372, 334-344.

Ettler et al. (2008) Atmos Environ, 42, 5968-5977.

Dating of young sediments, peat deposit

(~ 200 years)

I. separation of U a Th phases, which produce

highly radiogenic ratio

II. separation of Pb (sulphides) or phases

containing low amount of U, Th)

III. separation of Pb simultaneously with U a Th

206Pb, 207Pb, 208Pb a 204Pb isotopes

Origin of Pb Isotopic signature of geomaterials

depends on

• age of U, Th source

• separation of Pb (or U, Th) from the source

• one important source of Pb (eg. lithogical, ore)

• mixing of different sources

• combination of Pb and parent isotopes of U

and Th

• isotopic composition of the most important

sources

Origin of environmental Pb signature

A three-isotope plot

Mihaljevič et al. (2009) Int J Coal Geol 78, 38-46.

Ettler et al. (2004) Anal Bioanal Chem 378, 311-317.

Komárek et al. (2008) Environ Int 34, 562-577.

Material and methods

peat profiles

sedimentary profiles

soils

tree rings

soil and atmospheric waters

soils vs. biomass

Measurement of Pb

isotopic composition

Quadrupole based ICP MS (VG Elemental PQ3)

• the most preferred 206Pb/207Pb

ratio is used in environmental

science

• normalisation to 204Pb

(206Pb/204Pb,

207/Pb204Pb...) yields largest

variability between reservoirs

Pb mass spectrum

• important source of Pb

• different isotopic

composition

• depends on Pb source and U

U content

Mihaljevič et al. (2009) Int J Coal Geol 78, 38-46.

Coals

• source determination, mixing of sources

• determination of Pb penentration rate

Ettler et al. (2004) Anal Bioanal Chem 378, 311-317.

Soils

forest soil tilled soil

• changes in Pb source

Kadlec et al. (2009) Holocene, 19, 499-509

Morava River floodplain

Sediments

• source identification in industrial and remote areas

• deposition rates calculation

Mihaljevič et al. (2006) Sci Tot Environ 372, 334-344.

Peat deposits

• trees in temperate climate

have visually distinguishable

tree rings

• Pb is a suitable element for

dendroanalyses

• Pb source identification

by isotopic study

Tree rings

Mihaljevič et al. (2008) WASP 188,

311-321.

• source of Pb

• root uptake/interception

Mihaljevič et al. (2006) J Geochem Explor 88, 130-133

soils Prague

soils Most

Roudnice

wines

Plants- products

Zambia Copperbelt

Cu, Co ores

metallic and SO2

pollution

Ettler et al. Geoderma 164

Ettler et al. Geoderma 164

Copper

Cu

essential micronutrients

(enzymes, proteins)

also pollutant

Stable 63Cu (69.17 %) and 65Cu (30.83

%)

(27 radioisotopes)

Analytical techniques

Shields et al 1964, 1964 first

measurement of Cu isotopic ratio

First precise measurement of Cu

Merechal et al (1999) Chem Geol

Separation of Cu

- basic anion exchange resin

(BioRad, AG1-X) the separation of Cu from

matrix in Cl forms

Measurement

MC ICP MS with magnetic sector analyser

Standard NIST 976

bracketing or interelement (62Ni, 60Ni)

correction

Cu isotopic

Composition

of Cu minerals

Albarede (2004)

Meteorites – Luck et al (2004)

3 Cu reservoirs i) Earth like reservoir,

ii) Carbonaceous chondrites

iii) Mixture of i) and ii)

Luck et al GCA (2004)

Rocks

MORB, OIB – igneous processes are

inefficient in Cu fractionation

Sediments

Deep sea clays 65Cu -0,9 to – 3 ‰

preferential reductive dissolution of light

Isotope

Manganese nodulese preferential sorbtion

of heavy 65Cu

The 65Cu of natural materials Bigalke et al SSSAJ 2010

Fractionation of Cu isotopes Bigalke et al SSSAJ 2010

Albarede (2004) Rev Geochem Min

Soils

Bigalke et al. GCA 2010

Cu mg/kg 65Cu

Organic horizons are enriched in Cu,

and 65Cu

Pb and Cu isotopic study in Kombat

Kombat

Cu, Pb and Zn deposit

bornite chalcopyrite, galena, sphalerite,

tennantite, pyrite and,

chalcotite, digenite, malachite, covellite,

cuprite, native Cu and Ag

Closed in 2008, problems with flooding

Tailing dam 213 000m2

Sample Depth Fe tot Mn tot Cu d65Cu SD Pb

206Pb/207Pb SD

208Pb/206Pb SD

(cm) (mg kg -1) (mg kg -1) (mg kg -1) (‰) (mg kg -1)

K1 wet 0-20 4174 3811 1711,0 0,667 0,007 552,0 1,152601 0,002665 2,112931 0,007179

40-60 4452 5335 2625,0 0,820 0,006 827,0 1,151611 0,003431 2,107413 0,005186

160-180 13365 4038 4794 0,377 0,023 1904 1,151019 0,002969 2,10715 0,006333

K2 dry 0-20 7965 4349 1851 0,678 0,001 989 1,147687 0,003487 2,113504 0,008791

40-60 5670 2810 1199 0,612 0,008 689 1,150223 0,003994 2,118687 0,006194

160-180 4921 3664 2915 0,144 0,011 1120 1,14847 0,003902 2,11896 0,004147

Sample Depth TC TS Mineralogy

(cm) (%) (mg kg -1)

K1 wet 0-20 9,37 <100 Fe-dolomite, calcite, quartz, apatite, malachite, hematite rutile, muscovite

40-60 10,20 <100 Fe-dolomite, calcite, quartz, goethite, malachite, hematite, muscovite

160-180 10,11 <100 goethite, apatite, malachite, Fe-dolomite, calcite, quartz, hematite, rutile, muscovite

K2 dry 0-20 10,32 200 Fe-dolomite, calcite, goethite, apatite, malachite, quartz, hematite, muscovite

40-60 8,97 100 Fe-dolomite, apatite, calcite, goethite, quartz, rutile, malachite, hematite, muscovite, cerusite

160-180 9,23 300 fe-dolomite, apatite, calcite, quartz, rutile, cerusite, goethite, malachite, hematite, muscovite,

Tailing material

Cutanic luvisol Petrocalcic Chernozem

Cu and Pb speciation in tailing water

CuCO3aq (82 %), Cu(OH)aq+ (6.5%), Cu2+

(5.5 %), CuSO4aq (3 %), Cu(CO3)22-,

Cu(OH)2 (0.6%), CuHCO3+ (0.4 %).

uncharged Cu complexes (85.7%)

PbCO3 (64.2 %), PbSO4 (9.9 %),

Pb2+ (8.374 %), PbOH+ (8.1 %), PbHCO3+

(7.11), Pb(SO4)22- (0.5 %) and Pb(OH)2

(0.12 %) uncharged complexes 75%

of all forms of Pb

Leachate solution Lin STOTEN (1997)

Model equilibration with soil particles

(quartz, kaolinite, illite and hematite)

no data for SOM or Mn oxides

Cu in solution

< 3% Pb in solution

Soils contain birnesite and todorokite and

1,75-44 g/kg TC

Cu and Pb

correlation with

Mn contents

in soils

• metals are more mobile in luvisols compared

to chernozem

• Cu is more mobile than Pb

• basement rocks have negative 65Cu values,

the flotation waste of the tailing material has

positive 65Cu values

• the transformation of Cu to mobile forms 65Cu ↓

• bonding to Mn oxides in deeper parts 65Cu ↑

• plant activity 65Cu ↓

•The higher accesibility of ICP MS has led

to higher number of isotopic studies

•Pb isotopic composition were succesfully

used in environmantal studies as a

tracers

•Geochemical archives are powerful tool

for studying polution history

•Decline of Pb deposition since sewenties

Conclusion I

Conclusion II

• Determination of fractionation of

non-traditonal isotopes (Cu) are

dependent on very good resolution of MS

• Cu isotopic composition are succesfully

used in environmantal studies.

• Cu iso can serve as tracer of source

material

• Cu isotopes are successfully used for

Identification of biogeochemical cycling

Colleagues

V. Ettler, O. Šebek, L. Strnad, J. Jehlička, V. Chrastný (Č.

Budějovice), A. Vaněk, M. Komárek (ČZÚ) T. Navrátil (GÚ AV), T.

Kyncl, T. Grygar, D.R. Bowes, E. Dambrine, P. Povondra,

M.Fayadová

Students

Funding GAČR, GAUK, Phare, Ministry of Education...

Acknowledgements

Thank you for your attention