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  • Toxicology Centre

    Date of presentation Title or place of presentation

    Characterizing the toxicity of oil sands process affected waters (OSPW)

    Garrett Morandi PhD student

    SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    • 4 year NSERC Collaborative Research and Development grant • Awarded to Dr. John Giesy, Dr. Jon Martin, Syncrude Canada ltd.

    • Focused on characterizing the toxicity of the dissolved organic fraction of OSPW collected from Base Mine Lake (BML)

    SETAC 2016 November 10th, 2016

    Project overview. Toxicity Identification and Evaluation study

    BML, established December 2012

  • Toxicology Centre

    Date of presentation Title or place of presentation

    State of the science (2012).

    • Toxic effects of OSPW • Range of toxic effects have been observed across a number of species

    • Chemical culprits • Dissolved organic fraction is responsible for the majority of toxicity

    • Very complex mixture ~ 20,000 chemicals • Polar organic acids and semivolatile organic compounds (neutrals) are

    responsible for majority of toxicity (Mackinnon and Boerger, 1986 and Verbeek et al., 1993) • Long believed to be Naphthenic acids but never definitively demonstrated • Mode of action is narcosis (Frank et al., 2009)

    SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    Project overview.

    1. What heteroatom classes contribute to the acute toxicity of the dissolved organic fraction of OSPW?

    2. Do heteroatom atom classes in OSPW have the potential to bioaccumulate and can we predict their toxicity?

    3. Do these heteroatom classes have reproductive toxicity?

    SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    1. Identifying causative chemicals of toxicity.

    SETAC 2016 November 10th, 2016

    Approach. • Bioassay-effects directed analysis

    • Sequential fractionation and toxicity testing

    15- min IC50 Vibrio fisheri

    96-hr embryolethality assay Pimephales promelas

    Toxicity assays.

    Chemical analysis. • HPLC-Orbitrap uHRMS

  • Toxicology Centre

    Date of presentation Title or place of presentation

    What we did.

    F1

    F2

    F3 20 mg/L 14 mg/L

    Committee meeting November 25, 2014

    Sequential solvent extraction

    Sequential liquid- liquid wash

    Ion exchange column

    990 Seminar December 1, 2014 Qualifying exam September 2nd, 2015 SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation Qualifying exam September 2nd, 2015 SETAC 2016 November 10th, 2016

    Fraction 96-hr LC50 (X ± 95% CI)

    15 min IC50 (X ± 95% CI)

    F3-NE2a 0.73 (0.97) 1.23 (0.34) F3-NE2b 2.18 (0.36) 5.05 (2.47)

    Figure 1. Toxicity of fractions of OSPW to embryos of Fathead minnow.

    • Dose response of F3-NE2a indicative of a narcosis MOA

    • F3-NE2b MOA unknown

    Table 1. Toxicity of fractions of OSPW to embryos of Fathead minnow and Vibrio fisheri.

    Fraction concentration (x)

    0 2 4 6 8 10

    M or

    ta lit

    y (%

    )

    0

    20

    40

    60

    80

    100

    F3-NE2a F3-NE2b F3-Pool

    Toxicity results.

  • Heteroatom class

    O+ O2 +

    O3 +

    O4 +

    O5 +

    O6 +

    OS + O2

    S+ O3

    S+ O4

    S+ON + O2

    N+ O3

    N+ O4

    N+ ON

    S+

    O2 NS

    +

    In te

    ns ity

    0.0

    0.2

    0.4

    0.6

    0.8

    Heteroatom class

    O- O2 -

    O3 -

    O4 -

    O5 -

    O6 -

    OS - O2

    S- O3

    S- O4

    S- ON - O2

    N- O3

    N- O4

    N- ON

    S-

    O2 NS

    - 0.0

    0.2

    0.4

    0.6

    0.8

    F3-NE2a F3-NE2b

    • Evidence suggests that NA (O2-) are among the most potent chemicals in OSPW

    SETAC 2016 November 10th, 2016

    • But Other heteroatom classes contribute as well • O+, O2+, O3+, SO+, NO+

    Chemical characterization of tertiary fractions.

  • Toxicology Centre

    Date of presentation Title or place of presentation

    2. Assessing bioaccumulation potential of chemical species in OSPW and development of a predictive

    acute toxicity model

    SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    Biomimetic approaches to assess accumulation.

    TRANSIL® bead • Dmembrane/water

    • Mimics cell membrane • Ionic compounds

    DMW = 𝐶𝐶𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝐶𝐶𝑤𝑤𝑚𝑚𝑤𝑤𝑚𝑚𝑚𝑚

    Dow =

    𝐶𝐶𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙 𝐶𝐶𝑤𝑤𝑚𝑚𝑤𝑤𝑚𝑚𝑚𝑚

    ~

    PDMS stirbar • KPDMS

    • Neutral surrogate lipid • Neutral compounds

    KPDMS = 𝐶𝐶𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝐶𝐶𝑤𝑤𝑚𝑚𝑤𝑤𝑚𝑚𝑚𝑚

    • Can assess accumulation potential of chemical species in the whole mixture by use of lipid mimicking materials.

    SETAC 2016 November 10 th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    Results.

    • Deviation from linear relationship of DOW and DMW • Suggests differing potentials to accumulate of chemical species by use of the two

    methods

    Figure taken from Zhang et al., 2016

    SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    • All chemicals contributing to toxicity can be detected- Orbitrap MS- ESI+/-

    Development of a predictive toxicity model.

    Water concentration

    Toxicity endpoint

    1. 2.

    3.

    • Mode of action – Narcosis • Target lipid model can be used to predict toxicity by

    use of accumulation estimates (DOW/ DMW)

    SETAC NA 2015 November 4th, 2015

    • Toxicity of mixture follows concentration addition • Toxic units • Normalize aqueous concentration to

    hazard (LC50)

    CEW 2016 September 26th, 2016 SETAC 2016 November 10th, 2016

    Identify

  • Toxicology Centre

    Date of presentation Title or place of presentation

    Spreadsheet Model. Concentration: Toxicity:

    TU Calculated: (Concentration / Tox.)

    [M]i = (RIi ∗𝑴𝑴𝑴𝑴)Molecular mass i Log (LC50)i = -0.945log (DOW/DMW)i

    + Log Cbb

    Sum TU and predict toxicity

    Identify

    If TU ≥ 1 Expect LC50 or greater

    SETAC NA 2015 November 4th, 2015 CEW 2016 SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    96-hr embryo-lethality assay Pimephales promelas

    SETAC NA 2015 November 4th, 2015

    Test of model.

    CEW 2016 September 26th, 2016 SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    With observed

    LC50

    No observed

    LC50

    + F1-Pool

    + F2-Pool

    + F3-Pool

    No. samples

    Acute toxicity (LC50)

    8

    Total 10

    96-hr embryo-lethality assay Pimephales promelas

    SETAC NA 2015 November 4th, 2015

    Test of model.

    CEW 2016 September 26th, 2016 SETAC 2016 November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    Observed LC50 (mg/L)

    1e+0 1e+1 1e+2 1e+3 1e+4 1e+5

    Pr ed

    ic te

    d LC

    50 (m

    g/ L)

    1e+0

    1e+1

    1e+2

    1e+3

    1e+4

    1e+5

    Model results.

    November 4th, 2015 September 26th, 2016

    Fold difference from Observed

    LC50

    Model (n = 8)

    2 – fold 50% 4 – fold 75%

    > 10 - fold 0%

    Table 2. Percent of samples greater than X-fold different from observed.

    • All LC50s predicted within 10- fold of observed.

    Figure 2. Model predicted LC50 v. observed LC50, blue-line is a 5- fold difference from observed.

    November 10th, 2016

  • Toxicology Centre

    Date of presentation Title or place of presentation

    Chemical

    Class

    Percent TU (%) of dissolved organic fraction

    of OSPW

    C5-15 C16-20 C21-25 C26-30

    SO+ 5.79 20.3 2.59 3.25

    SO2- 0.85 7.75 0.15

  • Toxicology Centre

    Date of presentation Title or place of presentation

    Chemical

    Class

    Percent TU (%) of dissolved organic fraction

    of OSPW

    C5-15 C16-20 C21-25 C26-30

    SO+ 5.79 20.3 2.59 3.25

    SO2- 0.85 7.75 0.15

  • Toxicology Centre

    Date of presentation Title or place of presentation

    3. Reproductive toxicity of dissolved organic chemicals in OSPW

    SET

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