X' Chris Le

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Priority toxic elements (As, Sb, V) Source water
protection and drinking water treatment

• X. Chris Le
• Analytical Environmental Toxicology
• Department of Laboratory Medicine and Pathology
• Faculty of Medicine and Dentistry
• University of Alberta, Edmonton, Alberta

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X. Chris Le, U Alberta William R. Cullen,
UBCGeorge Dixon, U WaterlooGraham Gagnon,
Dalhousie UGary Kachanoski, U Alberta Patrick
Levallois, National Public Health Institute of
Quebec Kenneth J. Reimer, Royal Military College

• PIs of the Project Team

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Focus on water Arsenic, antimony, and Vanadium
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Chronic Exposure to Arsenic is a Worldwide Concern
Science, 296, 2143 (2002)
http//news.bbc.co.uk/2/hi/science/nature/6968574.
stm
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Relevance in Canada

• Most arsenic problems around the world are from
  well water
• 30 of the Canadian population rely on
  groundwater for domestic use

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Objective 1

• To characterize arsenic species and to determine
  human exposure to arsenic from drinking water
• This build on our expertise and specialized
  techniques

Synchrotron
LC-ICPMS LC-MS/MS
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Arsenic health effects

• Inorganic As causes skin, bladder, and lung
  cancers
• From hundred µg/L of As in water
• Water As guidelines 10 µg/L
• Effects from exposure to low levels of As are not
  well understood
• Exposure determination is critical

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Objective 2

• To establish biomarkers for human exposure and
  effects
• Urine
• Hair and Nails
• Saliva
• Blood
• Oxidative damage to cellular DNA

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Good correlation between exposure and urinary
excretion of As
2500
2000
R2 0.88987, N 118
1500
Arsenic in urine ( mg/L)
1000
500
0
0
200
400
600
800
Arsenic in water (mg/L)
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Arsenic concentration in saliva is correlated
with exposure to arsenic from drinking water
r0.610
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A CWN pilot study

• To evaluate biomarkers of exposure and effects in
  a Quebec population
• Urine arsenic metabolites
• Nail and hair arsenic
• 8OHdG and strand breaks in cellular DNA

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Objective 3

• To improve risk assessment by
• understanding arsenic metabolism and toxicity
• and understanding mechanisms of action

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(No Transcript)
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Arsenic Effects on DNA Damage and Repair
Human Cells
BPDE
Repair
Study DNA Repair
With or without arsenic
DNA damage
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Interaction of Arsenic with Proteins
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Studying Arsenic Health Effects

• Laboratory studies
• Understanding mechanisms of action
• Epidemiological studies
• Dose response relationship and exposure
  biomarkers
• Relevance to policy

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Risk Assessment
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Objective 4

• To develop technology for removal of arsenic from
  water

National Academy of Engineering Announces
Million-Dollar Challenge to Provide Safe
Drinking Water
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Quantitative PCR to evaluate arsenic mobility and
improve removal
ArsC Reduction
aroA Oxidation
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Arsenic Removal in Trail B. C.

• Cell Filling
• Biosolids (Celgar) from pulp and paper industry
  (75), sand (25). Mix in 25 limestone
• 2003
• 22,750 liters water from dump
• Input As 73 ppm
• Output As 7.2 ppm

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Objective 5

• Characterize and quantify arsenic, antimony, and
  vanadium species in oil sands by-products and
  processing water
• Investigate the bioavailability and toxicity of
  these element species to biota

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Vanadium in Oil Sands and By-products

• Vanadium species can be released from oil sands
  during processing
• Stability and leaching properties of vanadium
  species from coke (coal-like by-product) are not
  understood
• Toxicity of vanadium species V(V) gt V(IV) gt
  V(III)

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Separation of V in pore water from oilsand
by-products (coke)
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Reduction of vanadium by bacterium S.
putrefaciens CN32
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Determine Bioaccumulation to Effect Relationship
for Vanadium
Chronic (4 week) toxicity tests with Hyalella
azteca
Hypothesis Bioaccumulation can be used to
predict toxicity.
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Tissue
Risk Analysis
Other Causes
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Research Outcomes

• Knowledge on the sources and levels of human
  exposure
• Improved understanding of arsenic health effects
  for more meaningful risk assessment
• Treatment technology
• Policy relevance

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Key partners

• Alberta Health and Wellness
• EPCOR Water Services, Edmonton
• Goldbar Waste Water Treatment Plant, Edmonton
• Health Canada
• Nature Works Remediation, Guelph
• Syncrude Canada
• Trojan UV Technologies, London
• U.S. Environmental Protection Agency

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Linkages and leverage

• Alberta Water for Life Strategy
• American Water Works Association Research
  Foundation (USA)
• Canadian Cancer Society
• Environmental Protection Agency (USA)
• National Cancer Institute (USA)
• gt10 collaborators in China, Europe, Japan, and
  USA

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William R. Cullen, UBCGeorge Dixon, U
WaterlooGraham Gagnon, Dalhousie UGary
Kachanoski, U Alberta Patrick Levallois,
National Public Health Institute of Quebec
Kenneth J. Reimer, Royal Military College X.
Chris Le group at U Alberta

• Cross-disciplinary expertise

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Overall Objectives

• Develop specialized techniques for analysis of
  toxic elements in water
• Characterize and quantify arsenic, antimony, and
  vanadium species in drinking water and oil sands
  by-products
• Investigate the toxicity of these element species
  to biota and to humans
• Evaluate human exposure and effects biomarkers
• Develop technology for removal of toxic elements
  from water

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Chris Le Research Group
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CWN Project Collaboration

• Health Canada
• Environment Canada
• Provincial health and environment departments
• Water utilities (e.g., EPCOR)
• gt15 international collaborators
• gt20 partners and collaborators in Canada

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Acknowledgements

• Richard Charron, Michelle Giddings, John Cooper,
  Health Canada
• Judy Mumford, Environmental Protection Agency
• Stephan Gabos, Alberta Health and Wellness
• Mark Servos, Canadian Water Network
• The Le research group

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Arsenic Effects on DNA Damage
Human Cells
With or without arsenic
BPDE
Measure DNA Damage
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Acknowledgements Funding