Impact of Arsenic from CCA-Treated Wood in Marine and Terrestrial Environments A Collaborative...

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Transcript of Impact of Arsenic from CCA-Treated Wood in Marine and Terrestrial Environments A Collaborative...

Impact of Arsenic from CCA-Treated Wood in Marine and Terrestrial

Environments

A Collaborative Research between FIU and UM

Supported by NIEHS-ARCH Program

AcknowledgmentsAcknowledgments

FIUFIUMyron GeorgiadisMyron GeorgiadisSheena Powell SzuriSheena Powell Szuri

UMUMDr. Helena Solo-GabrieleDr. Helena Solo-GabrieleBernine KhanBernine Khan

GoalsGoals

• To develop analytical techniques for arsenic To develop analytical techniques for arsenic speciation in leachate of CCA-treated wood speciation in leachate of CCA-treated wood and surrounding soils . and surrounding soils .   

• To develop an analytical procedure for To develop an analytical procedure for arsenic speciation based on the partitioning arsenic speciation based on the partitioning of arsenic compounds between different of arsenic compounds between different molecular-weight fractions in leachatemolecular-weight fractions in leachate

Effects of POEffects of PO44 Concentration Concentration(PACS-2)(PACS-2)

As(III) PO4 Extraction3 hours

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PO4 (mM)

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(mg

/g)

Effects of POEffects of PO44 Concentration Concentration

(PACS-2)(PACS-2)

As(V) PO4 Extraction

3 hours

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PO4 (mM)

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HG-AFSHG-AFS and ICP-MS Comparison and ICP-MS Comparison

Total As Concentration Over Time

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Time Extracted (Hours)

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Average ICP-MS (ppb) Average HG-AFS (ppb)

Effects of Extraction TimeEffects of Extraction Time(PACS-2)(PACS-2)

Timed 10mM PO4 Extraction

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1 3 5 12 24Time Extracted (Hours)

m g/g

As(III)

Effects of Extraction TimeEffects of Extraction Time(PACS-2)(PACS-2)

Timed 10mM PO4 Extraction

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Time Extracted (Hours)

m g/g

As(V)

Effects of Extraction TimeEffects of Extraction Time(PACS-2 spiked with arsenite)(PACS-2 spiked with arsenite)

As(III) Stability

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Time Extracted (Hours)

m g/g

As(III)

Effects of Extraction TimeEffects of Extraction Time (PACS-2 spiked with arsenite)(PACS-2 spiked with arsenite)

As(V) Stability

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Time Extracted (Hours)

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As(V)

10mM PO4, 5 Hour Extraction

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EDTA Concentration (mM)

m g/g

As(III) As(V)

Effects of EDTAEffects of EDTA(PACS-2 spiked with arsenite) (PACS-2 spiked with arsenite)

10 mM PO4, 5 Hour Extraction

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EDTA Concentration (mM)

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As(III) As(V)

Varying EDTA ConcentrationVarying EDTA Concentration(PACS-2 spiked with arsenate) (PACS-2 spiked with arsenate)

50 mM EDTA, 10 mM PO4

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Time Extracted (Hours)

m g/g

As(III) As(V)

Everglades Soil SampleEverglades Soil SampleSpiked with Arsenite (2 Spiked with Arsenite (2 mmg/g)g/g)

Everglades Soil SampleEverglades Soil Sample Spiked with Arsenate (4 Spiked with Arsenate (4 mmg/g)g/g)

50 mM EDTA, 10 mM PO4

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Time Extracted (Hours)

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As(III) As(V)

Average Recovery of Arsenite and Arsenate

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Equilibrium Dialysis

Average Recovery by Molecular Weight Cutoff

Total Arsenic from Leachate after 24 Hours

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Inside Outside

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Total Arsenic from two Leachates using two Molecular Weight Cutoff Sizes after 24 hour Dialysis.

Leachate 1 Leachate 1

Leachate 2