RESPONSE OPTIONS: BIOLOGICAL RESPONSE INDICATOR DEVICES FOR GAUGING ENVIRONMENTAL STRESSORS (BRIDGES), EXAMPLES: DEEPWATER HORIZON OIL SPILL & SUPERFUND SITES

RESPONSE, RECOVERY, AND RESILIENCE TO OIL SPILLS AND ENVIRONMENTAL DISASTERS: ENGAGING EXPERTS AND COMMUNITIES A SYMPOSIUM AND WORKSHOP FOR COMMUNITY STAKEHOLDERS, RESEARCHERS AND POLICY MAKERS JANUARY 29, 2013ENERGY, COAST AND ENVIRONMENT BUILDING, WOODS AUDITORIUM, LSU CAMPUS, BATON ROUGE, LA 70803

Kim A. Anderson, PhDProfessor, Environmental & Molecular ToxicologyDirector, Food Safety & Environmental Stewardship ProgramOregon State University

Sampling Design: Responding in Different Ways and WhyBioavailability: target organisms and passive sampling devices

Freely dissolved*

Can be taken up by organisms

2

Total concentration

Bioavailable fraction

Potential for exposure

RISK

• Adams, et al 1985, DiToro et al 1991• The PAHs most available to equilibrate are those that are freely dissolved, since these are capable of transferring from one

phase to another and passing through biological membranes.” (Wang and Fisher, 1999)• It is generally believed that the process of uptake of these neutral hydrophobic compounds is PASSIVE and controlled

DIFFUSION pressures (fugacity) because of the differential between the environment matrix and tissue concentrations. UPTAKE from water is generally accomplished by ventilation over the gill structure, although diffusion through the integument may also contribute to tissue concentrations (Landrum and Stubblefield, 1991, Douben 2003)

• “For PAHs with log Kow ≤ 5.5 the main route of uptake is through ventilated water”, …those >5.5 ingestion of food or sediment increases in importance although not well understood…( Landrum 1989, Landrum and Robbins, 1990, Meador et al 1995, Douben 2003). Oregon State University

Why Bioavailable ?

Understanding environmental factors on diseases… Must develop new bio-

analytical tools to measure exposure

L.S. Birnbaum, EHP, 2010

Intelligent sampling

Environmental exposure

Bioavailability BRIDGING

environmental exposure with biological responses

Environmental exposure and fate

Thinking outside the sampling jar

3

Oregon State University

BRIDGES B e y o n d Chemical Analysis

Environmental Concentrations

For example:source, route, quantity

Environmental Chemistry

Exposure

Environmental Fate

For example: transport, distribution,

degradation

Toxicology

Effect

Toxico-kinetics

For example:Uptake, metabolism,

elimination

Toxico-dynamicsFor example: effects

across levels of biological organization

Bioavailability

Cell MembranePSD Membrane

Biological Response Indicator Devices for Gauging Environmental StressorsBRIDGES

Responding design options PSD: Relevant to a range of contaminants

Extract clean PCBs, Pesticides, PBDEs, … 1,200+ analyte screen LC or GC compatible PAHs (b e y o n d 16 EPA) 302 mw, dibenzopyrene

isomers PAHs Layshock et al JEM, 2010

Oxygenated PAHs (ketones, quinones) Layshock and Anderson, ET&C, 2010

Numerous Chemistry Opportunities

Numerous Environments

6

Oregon State University

PSD: Relevant to a range of contaminants in water, air, sediment, etc….

Pesticides, … 1,200+ analyte screen LC or GC compatible

Numerous Chemistry Opportunities

In-situ Calibration

7

Oregon State University

PRC- Performance Reference Compounds –Isotopically Labeled Compound

Sequestered Environmental Contaminants

t=0

PSD: Relevant to Rapid Response

Easy to deploy Easy to transport

8

Oregon State University

BRIDGES: Reduce exposure uncertainty by analyzing biological responses

BRIDGES extracts with bioassay model (Zebrafish, Ames, etc) system

BRIDGES well suited for effects-directed analysisBRIDGES designed for relevant mixtures

9

pre

p m

ix

pre

p m

ix

pre

p m

ix

test @ day 1

•mortality•morphology•movement

1 embryo per

male female

VV

fertilized eggs

test @ day 5

•mortality •morphology •hatch rate•swimming

96 well plate

fiel

d e

xtra

ct

Toxicological Responses

pre

p m

ixp

rep

mix

pre

p m

ixp

rep

mix

pre

p m

ixp

rep

mix

test @ day 1

•mortality•morphology•movement

1 embryo per

male female

VV

fertilized eggs

test @ day 5

•mortality •morphology •hatch rate•swimming

96 well plate

fiel

d e

xtra

ctfi

eld

ext

ract

Toxicological Responses

PSD cage

weight

float buoy

top buoy

10 ft PSD cage

weight

float buoy

top buoy

10 ftquantify

PCBPAHPAH-metabolites

extraction

dialysisfield deployment

fiel

d e

xtra

ct

Environmental Exposure

PSD cage

weight

float buoy

top buoy

10 ft PSD cage

weight

float buoy

top buoy

10 ftquantify

PCBPAHPAH-metabolites

extraction

dialysis

solvent exchange

field deployment

fiel

d e

xtra

ct

Environmental Exposure

pre

p m

ix

pre

p m

ix

pre

p m

ix

test @ day 1

•mortality•morphology•movement

1 embryo per

male female

VV

fertilized eggs

test @ day 5

•mortality •morphology •hatch rate•swimming

96 well plate

fiel

d e

xtra

ct

Toxicological Responses

pre

p m

ixp

rep

mix

pre

p m

ixp

rep

mix

pre

p m

ixp

rep

mix

test @ day 1

•mortality•morphology•movement

1 embryo per

male female

VV

fertilized eggs

test @ day 5

•mortality •morphology •hatch rate•swimming

96 well plate

fiel

d e

xtra

ctfi

eld

ext

ract

Toxicological Responses

PSD cage

weight

float buoy

top buoy

10 ft PSD cage

weight

float buoy

top buoy

10 ft PSD cage

weight

float buoy

top buoy

10 ft PSD cage

weight

float buoy

top buoy

10 ftquantify

PCBPAHPAH-metabolites

extraction

dialysisfield deployment

fiel

d e

xtra

ct

Environmental Exposure

PSD cage

weight

float buoy

top buoy

10 ft PSD cage

weight

float buoy

top buoy

10 ft PSD cage

weight

float buoy

top buoy

10 ft PSD cage

weight

float buoy

top buoy

10 ftquantify

PCBPAHPAH-metabolites

extraction

dialysis

solvent exchange

field deployment

fiel

d e

xtra

ct

Environmental Exposure

Hillwalker, Allan, Tanguay, & Anderson Chemo. 2010Oregon State University

Bio-analytical ToolsBRIDGING Environmental Exposure with Biological Responses

Integrated with Bioassays (in vivo and in vitro)

Evaluating whole mixture, real exposures Suitable to mixture

assessment PAHs, PCBs, Pesticides 1,200+ analytes screen Oxygenated PAHs

Layshock et al ETC, 2010

Zebrafish Embryonic Model

Oregon State University

Sources of PAHs in the Environment

Biogenic (minor) Petrogenic

Generated by geological processes NATURAL- seeps, coal

outcrops ANTHROPOGENIC –fossil fuel

release Pyrogenic

Generated by high temperature combustion of organic matter NATURAL –forest fires ANTHROPOGENIC- wood

stoves, car exhaust, coal tar

2010 June Sampling Campaign, FL, tar-ball (photo KA Anderson)

Oregon State University

Oil Spills Context and ComparisonsIt doesn’t take much seep oil to deliver a lot of PAHs

1 kilogram of oil contains as much PAH as a metric ton of coal

Crude oil PAHs vary by crude oil type, 0.2 to 7% PAHs

DW Horizon spill PAH* 5,000– 7,000 m Ton

World Trade Towers PAH 100 – 1,000 m Ton

Oregon State University

RESPONSE: May 1 Planning StartedComplicated Ops, multi-sources, sites, access14,000 wells in GoM, 79 incidents of loss of well control

13

Oregon State University

Ready Response…The FSES Program at OSU is a research program committed to providing the highest quality analytical laboratory research support for:

ESTABLISH background Pre-spill Many sites oil present Quality Control

Trip blanks Field blanks Laboratory QC

Quality Assurance Established protocols Documentation Staff trained

Quality Assurance Program PlanDefensible, Unbiased data

Oregon State University

Respond: establish regional and individual contacts

Florida Pensacola, Gulf Islands National

Seashore Permit required, yes, State of FL

Alabama Mobile, Ben Secour National Wildlife

Refuge Permit required, yes, State of AL

Mississippi Gulf Port, Public Pier

currently closed due to construction

Gulf Port Harbor Master,

Louisiana Grand Isle State Park

Permit required, yes, State of LA16

Image: http://www.nytimes.com

Oregon State University

17 Grand Isle, LA Gulf Breeze, FL

Gulf Shores, ALGulf Port, MS

Response Goals: many fold…Many ideally suited to passive samplers

PRE-spill conditions

Oil trajectory uncertain

Broad geographic areas “at risk”

Time-scale

Defensible, Unbiased data

New technology and capabilities – goals

Bioavailable passive samplers

used for BRIDGES (biological response indicator devices for gauging environmental stressors )

Passive Sampler for aquatic exposures and NEW PSD air sampler

Suitable for chemical mixtures

Both chemical and bio-assays

Quality Control, PRCGrand Isle, LA, Research June 2010 Sampling Campaign (photo: KA Anderson)

Temporal, Spatial PAHs Gulf of MexicoBioavailable Water Concentrations of PAHs (ng/L)

ƩPAH

-Bi

oava

ilabl

e co

ncen

trati

onin

wat

er (n

g/L) Gulf Shores, AL

Sampling Event

P

AH

- B

ioa

va

ila

ble

co

cn

en

tra

tio

n i

n w

ate

r (n

g/L

)

0

10

20

30

Gulf Breeze, FL

Sampling Event

PA

H -

Bio

ava

ila

ble

co

cn

en

tra

tio

n i

n w

ate

r (n

g/L

)

0

10

20

30

2010 2011

Grand Isle, LA

Sampling Event

PA

H -

Bio

ava

ilab

le c

ocn

en

trati

on

in

wa

ter

(ng

/L)

0

50

100

150

200

Gulfport, MS

Sampling Event

PA

H -

Bio

ava

ila

ble

co

cn

en

tra

tio

n i

n w

ate

r (n

g/L

)

0

10

20

30

Gulf Shores, AL

Sampling Event

PA

H - B

io

availab

le co

cn

en

tratio

n in

w

ater (n

g/L

)

0

10

20

30

Gulf Breeze, FL

Sampling Event

PA

H - B

io

availab

le co

cn

en

tratio

n in

w

ater (n

g/L

)

0

10

20

30

2010 2011

Ʃ33

PA

H –

Bio

ava

ila

ble

co

nc

en

tra

tio

n in

wa

ter

(ng

/L)

*

19

Allan, Smith & Anderson, ES&T 2012

2010 day:

131-134

2010 day:

159-162

2010 day:

162-188

2010 day:

188-271

2010 day:

217-252

2010 day:

252-287

2010 day: 287 to 2011 day: 40

2011 day: 40-

74

2011 day: 74-

115

2011 day:

115-119

2011 day:

119-158

012345678

Louisiana

phenanthrene1-methylphenanthrene2-methylphenanthrene3,6-dimethylphenanthrene

PA

Hs in n

g/m

³ air

2010 day: 131-

134

2010 day: 159-

162

2010 day: 162-

188

2010 day: 188-

271

2010 day: 217-

252

2010 day: 252-

287

2010 day: 287 to 2011 day: 40

2011 day: 40-

74

2011 day: 74-

115

2011 day: 115-

119

2011 day: 119-

158

0

1

2

3

4

5

6

7

8

Mississippi

phenanthrene1-methylphenanthrene2-methylphenanthrene3,6-dimethylphenanthrene

PA

Hs in n

g/m

³ air

Temporal, Spatial PAHs Gulf of MexicoBioavailable Air Concentrations of a selected PAH (ng/m3)

Temporal, Spatial Surfactants Gulf of MexicoDispersants contain surfactants (detergent like)

Surfactants captured by passive sampling devices

~1.8 million gallons used in DWH (Macondo well explosion)

Effective response to many issues surrounding an oil spill or environmental spill/disaster

Often reference control will be (initially) unknown (e.g. Corexit 9527 and 9500)

First field dispersant used April 20-26

21

S-

O

OO

S-

O

O

O

C16H25O 3S

C16H 25O 3S

Oregon State University

0

5000

10000

15000

20000

25000

30000C16H25O3SC17H27O3SC18H29O3SC19H31O3S

0

5000

10000

15000

20000

25000

30000C16H25O3SC17H27O3SC18H29O3SC19H31O3S

0

5000

10000

15000

20000

25000

30000C16H25O3S

C17H27O3S

C18H29O3S

C19H31O3S

0

5000

10000

15000

20000

25000

30000

C16H25O3SC17H27O3SC18H29O3SC19H31O3S

Analyzing the ‘fingerprint’ in a chemical profile

Oregon State University

Analyzing the chemical ‘fingerprint’ (petrogenic -v- pyrogenic)

PAH Forensic Profile GoM before, during, after

23

Gulf Shores, AL

Sampling Event

May 2010 September May 20110

20

40

60

80

100

C0 NAP C1 NAP C3 NAP

Gulf Breezes, FL

Sampling Event

May 2010 September May 20110

20

40

60

80

100

Grand Isle, LA

Sampling Event

May 2010 June (1) May 20110

20

40

60

80

100

Gulfport, MS

Sampling Event

May 2010 June (1) May 20110

20

40

60

80

100re

lati

ve a

bu

nd

ance

(%

of

tota

l n

aph

thal

ene

com

po

un

ds)

0

0.25

0.5

0.75

1

C0 C1 C2 C3 C4 C0 C1 C2 C3 C4

Normalized %

Pyrogenic Petrogenic

0

0.25

0.5

0.75

1

C0 C1 C2 C3 C4 C0 C1 C2 C3 C4

Normalized %

Pyrogenic PetrogenicPyrogenic Petrogenic

Principle Component Analysis1-9 = May 2010 through June 2011 water PAHs24

Allan, Smith & Anderson, ES&T 2012 Oregon State University

Hopanes: Used to Determine SourcesMolecular Fossils, Biomarkers

Organic compounds in petroleum whose chemical structure can be unequivocally linked to a naturally occurring sources

Complex, naturally occurring, compounds that are resistant to weathering & biodegradation

Hopanes captured by passive sampling devices (PSD)

PSD conserve forensic profiles Hopane ratio profile changes

25

Oregon State University

0.00

5.00

10.00

15.00

20.00

25.00

30.00

Ra

tio

Va

lue

Sample Name

Alabama Hopane Ratios

C27Ts/C27m

25norC29αβ/C30αβ

C27ββR/C30ββR

25norC29αβ/C30ββ

C29αβ/25norC29αβ

C29αβ/C30αβ

C30αβ/C30βα

C30βα/C30ββ

C30βα/C30αβ

C29αβ/C30βα

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

Ra

tio

Va

lue

Sample Name

Florida Hopane Ratios

C27Ts/C27m

25norC29αβ/C30αβ

C27ββR/C30ββR

25norC29αβ/C30ββ

C29αβ/25norC29αβ

C29αβ/C30αβ

C30αβ/C30βα

C30βα/C30ββ

C30βα/C30αβ

C29αβ/C30βα

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

Ra

tio

Va

lue

Sample Name

Mississippi Hopane Ratios

C27Ts/C27m

25norC29αβ/C30αβ

C27ββR/C30ββR

25norC29αβ/C30ββ

C29αβ/25norC29αβ

C29αβ/C30αβ

C30αβ/C30βα

C30βα/C30ββ

C30βα/C30αβ

C29αβ/C30βα

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

C27Ts/C27m

25norC29αβ/C30αβ

C27ββR/C30ββR

25norC29αβ/C30ββ

C29αβ/25norC29αβ

C29αβ/C30αβ

C30αβ/C30βα

C30βα/C30ββ

C30βα/C30αβ

C29αβ/C30βα

Other Applications

Passive sampling devices capable of capturing a wide range of chemicals suitable for characterizing environmental exposure, and profiling chemicals for source identification

Temporary increase in bioavailable PAHs Associated with more petrogenic PAH assemblage and

characteristic change in chemical profile Pre-oiling levels at all sites by March, 2011 Elevated concentrations in AL in April and May,

2011

APPLICABLE to other environmental disasters, Superfund sites, remediation assessment examples…

PSD: Bioavailable PAHs Before and After Remediation High Spatial Resolution Possible with PSDsMcCormick and Baxter Superfund Site, OR; before max ~800, post <50 ng/L

27

Oregon State University

Monitoring design options PSD Integrated Seamlessly with Bioassays in vivo and in vitro embryonic zebrafish model, Ames test

Assessment of field deployed LFT's mutagenicity in the Ames assay using test strain TA-98 with

metabolic activation (S9+) (mean +/- SE; n = 3)

Dose of LFT extract (uL/plate)

+ CTRL - CTRL 5 25 50

His

+ r

ever

tant

s/pl

ate

0

25

50

75

LFT - RPH09-0232 g of 2AADMSO (50 L)

Realistic MixturesPH Superfund RM =3.5W

Relevant MixturesPH Superfund RM = 7W

28

Allan, SE, Smith, BW, Tanguay, RL, and Anderson KA, Environ Tox & Chem, in press 2012 Oregon State University

Site-specific Biological Responses

6 of 18 biological responses were significantly different in exposed embryos compared to controls

MLR, likelihood ratio, p<0.05;

n = 941

Hillwalker, Allan, Tanguay, and Anderson Chemosphere, 2010,

BRIDGES

M30

1 2 3 4 5 60

20

40

60

80

M126

1 2 3 4 5 60

20

40

60

80126 hpf mortality

Stubby

1 2 3 4 5 60

20

40

60

80stubby body

Tail

1 2 3 4 5 60

20

40

60

80bent tail

YSE

1 2 3 4 5 60

20

40

60

80yolk sac edema

Notochord 126 hpf

1 2 3 4 5 60

20

40

60

80wavy notochord

% In

cid

en

ce

Control Embryos

RM 1

RM 3.5

RM 7E

RM 7W

RM 17

Downriver Superfund Upriver

30 hpf mortality

X

X

X

X

Hillwalker, Allan, Tanguay, & Anderson Chemo. 2010

Estimating exposure (risk) using PSDs as biological surrogates in human health risk models

Apply PSD data in a Public Health Framework PSDs may be used as a biological

surrogate Added spatial and temporal

variations in potential human health estimate of exposures

Method Calculating Exposure PSDs were substituted for fish

tissue

Exposure from resident organisms Tissue contaminant data

Difficult to obtain fish/shellfish Destructive sampling Inherent biological/physiological

variability Limited spatial/temporal

information Not responsive quickly

enough for assessment to immediate changes

30

Allan, Sower & Anderson, Chemo. 2011

Comparison of PSD as a surrogate and fish tissue31

RM 3-7 RM 8-13 RM 15-18

bio

ava

ila

be

DD

Ts (

pg

/L)

0

200

400

600

800

bioavailable concentrations by PSD

X Data

RM 3.5 - 7 RM 8 - 13 RM 15 - 18

bio

availa

ble

PC

Bs (

pg/L

)

0

20

40

60

80

100

120

PCBs

RM 3 - 6 RM 8 - 11 RM 14 - 16

P

CB

s in

fis

h (

ng/g

)0

100

200

300

400

500

600

PCBs

RM 3-7 RM 8-13 RM 15-18

bio

ava

ila

ble

die

ldri

n (

pg

/L)

0

20

40

60

80

dieldrin

RM 3-6 RM 8-11 RM 14-16

die

ldri

n in

fis

h (

ng

/g)

0

1

2

3

4

5

dieldrin

RM 3-6. RM 8-11 RM 14-16

D

DT

s in

fis

h (

ng

/g)

0

100

200

300

400

concentrations in fish

Sethajintanin et al. 2004, Villeneuve, et al, ES&T, 2005

DDTs SDDTs

Paired PSDs deployed with crayfish cages, PAHs… to date, outstanding fit with measured and modeled

[NA

P] W

-PS

D (

ng/L

)

-20

0

20

40

60

80

100

120

[NA

P] C

F (

ng/g

)

-20

0

20

40

60

80

100

120

[AN

T] W

-PS

D (n

g/L

)

-10

0

10

20

30

40

50

[AN

T] C

F (n

g/g

)

-20

0

20

4050

100

150

200

250

[BA

A] W

-PS

D (n

g/L

)

0

20

40

60

80

[BA

A] C

F (n

g/g

)

0

10

20

100

200

300

400

18.5 17 13 8

7e -

South

7e -

Centra

l

7e -

North 7w 3.

5

[BK

F] W

-PS

D (n

g/L

)

0

5

10

15

20

[BK

F] C

F (n

g/g

)

0

5

20

40

60

80

Naphthalene Anthracene

Benz[a]anthracene Benzo[k]fluoranthene

Figure 4. Comparisons between PAH levels measured in paired passive sampling devices ( ) and crayfish ( ) from within and outside of the Portland Harbor Superfund site. Data are the mean and standard deviations of replicate samples.

PAHs in PSDs vs. Crayfish

Model Fitting DiagnosticsM

easu

red

in C

rayfi

sh

Predicted in Crayfish

Naphthalene Anthracene Benz[a]anthracene Benzo[k]fluoranthene

Response design options Comparison of PSDs and fish tissue

Although not enough side-by-side studies Currently side-by-side in progress (n=75 crayfish : PSD) at our

laboratory

PSDs as biological surrogates may provide a reasonable and conservative estimate of exposure Another data set contributing to protection of human health Does not appear to significantly overestimate risk Quickly assess environmental disasters before resident

organisms respond Magnitude, range and variability assets of the technique

33

≈Allan, Sower & Anderson, Chemo. 2011

Other types of passive sampling devicesResponder’s Exposure….

TBS NIOHS- Feb 5 Interdisciplinary Co-PIs Laurel Kincl (CPHHS) &

K.A.Anderson, co-I’s Tanguay, Sudakin, Kile

Wristband Preliminary Data: PAHs from Roofers for 8 and 40 hrs

Funding: Environmental Integrated Organic Monitor of Exposure (Einome)

0

1000

2000

3000

4000

5000

Participant 1 Participant 2 Participant 3

ng/m

L

Sum PAHs

Einome: 40 hrs

Lapels

Double WBs

WBs

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

PAH Sum

WB 1 - day

WB 2 - day

WB 3 - day

WB 1 - week

WB 2 - week

WB 3 - week

Community Outreach and Engagement StrategiesGoal: Provide pertinent PAH health information to be delivered using novel methods via the web.

Develop and deliver educational materials at gulf sampling locations (e.g. printed brochure)

Develop local partnerships to identify educational needs NIEHS SRP at Louisiana State University State and local organizations, including non-

governmental organizations located in Gulf states

Develop novel outreach methods for public education

Please see web sites and videos Oregon State University

Anticipated IMPACT

RESPOND

Easy deployed

time-integrate

d sampling devices

RECOVERY

1,200 bioavailabl

e contamina

nts monitoring

RESILENCE

Characteri

ze and updated

information

Next Health

Assessment:

Surrogate fish/shell

fish

36

Acknowledgements37

Funding:P42 ES016465 (PI Williams, Project Leader Anderson, Analytical Core leader Anderson)P30 ES000210 (PI Beckman)R21 ES020120 (PI Anderson)UN FAO GEF, (Co-PIs: Jepson, Anderson, Jenkins)

Collaborators:Oregon State UniversityProfessor Robert Tanguay, SRP Co-IProfessor Anna Harding, Co-IProfessor Dashwood, Linus Pauling Institute, CCP Core, David Yu, PhD. (Ames)

Pacific Northwest National LaboratoryKatrina Waters, PhD

Collaborators:

Swinomish Indian Tribal CommunityConfederated Tribes of the Umatilla Indian Reservation

Oregon Dept of Environmental QualityKevin Parrot and Sott Manzano

Grand Isle State Park, LA, T. Augustine

MS Gulf Port Harbor Master, DJ Ziggler

Mobile AL Ben Secour National Refugre, J. Issacs

Pensacola FL Gulf Islands National Seashore, R. Hoggard

Acknowledgements

http://fses.oregonstate.edu GULF Outreach

http://oregonstate.edu/superfund/oilspill

38

Kevin HobbieTed HaighMelissa McCartneyGlenn WilsonJennifer PrzybylaSarah Allan, PhDNorm ForsbergSteven O’ConnellLane TidwellPhil JanneyRicky Scott

Nick Hamilton Jorge PadillaKristin PierreNathan RooneyKyle TidwellBrian Smith, PhD

Not pictured: Jeremy Riggle, PhDJulie Layshock, PhD. Hillwalker, W., PhD

Greg Sower, PhDAngie Perez, PhDLucas Quarles, MSSolysa VisalliMargarett Corvi, MSO. Krissanakriang, PhDD. Sethajintanin, PhD

Oregon State University