Lingering Exxon Valdez Oil Remains the Dominant Cause of CYP1A Induction in Prince

William Sound, Alaska

National Marine Fisheries ServiceAuke Bay Fisheries LaboratoryAuke Bay, Alaska USA

J W Short, S D Rice1

K R Springman2

C A Sloan3

C W Khan, P V Hodson4

1 Alaska Fisheries Science Center, NOAA2 U California Davis3 Northwest Fisheries Science Center, NOAA4 Queen’s University, Canada

How do we measure oil exposure?

Cytochrome P450 1A (CYP1A) biomarker

• One of a family of enzymes involved in metabolism and detoxification

• Induced by recent exposure to polycyclic aromatic hydrocarbons (PAHs) and PCBs

Cyp 1A Induction and Long-Term Effects in EVOS Spillpath Otters and Ducks:

Geographically Associated with Lingering Oil

Temporal Declines Since Early 1990s

Remnant Fuel Tanks at Thumb Bay

Other Potential Sources of CYP1A Inducers in Western PWS

Atmospherically Transported PAH, POP

Regional Geologic Background PAH

Returning Adult Salmon

Salmon Hatcheries

Abandoned Industrial Sites

Marinas & Boat Traffic

Cordova Harbor – Positive Control

Study Objective:

Identify Sources of CYP1A Inducers in Western Prince William Sound

Site Selection: Site Site Selection: Site TypesTypes

Above: Salmon Above: Salmon StreamStream

Top: Hatchery Top: Hatchery Bottom: Human UseBottom: Human Use

SPMD Application: SPMD Application: DeploymentDeployment

One deployment One deployment device = 5 SPMDsdevice = 5 SPMDs

28 d 28 d in situin situ (SOP) (SOP) Placed in the mid- Placed in the mid-

intertidal zoneintertidal zone

SPMD ModificationSPMD ModificationSPMDSPMD DialysisDialysis ConcentrationConcentration Split Split

samplesample

Analysis Analysis

Removal of Removal of hexanehexane

Resuspension in Resuspension in solventsolvent

Injection in Injection in trout frytrout fry

Chemical Analyses:

44 PAH, including alkyl-PAH

62 Chlorinated POPs

Sampling Design

Regional Background PAH, POP - 30 Randomly-Placed SPMDs

Exxon Valdez Sites – 9 SPMDS on 5 Beaches

Salmon Streams – 10 SPMDs, Spring and Fall

Salmon Hatcheries – 5 SPMDs

Abandoned Industrial Sites – 5 SPMDs

Two Marinas – 1 SPMD Each (Positive Controls)

POP Results

Highest ΣPCB < 200 ng/SPMD(Median = 12 ng/SPMD; N =

76)Other POPs Near MDLs

POPs, EROD Uncorrelated

PWS 2004: Sampling Sites

Cordova

Valdez

Whittier

EVO control (5)EVO hot (5)

Background (30)

Salmon stream (5)

Human Activity (5)

Positive control (2)

Hatchery (5)

Diesel spill (1)

EVO Sites Cordova Harbor

PA

H (n

g/S

PM

D)

103

104

105

106

ER

OD

Act

ivity

(pm

ol/m

g/m

in)

0

20

40

60

80

100TPAH Chrysenes EROD

N = 9

PWS 2004: Random Sites

Cordova

Valdez

Whittier

Background (30)

Positive control (2)

Random Sites Cordova Harbor

PAH

(ng/

SPM

D)

103

104

105

106

ERO

D A

ctiv

ity (p

mol

/mg/

min

)

0

20

40

60

80

100TPAH Chrysenes EROD

N = 10

PWS 2004: Salmon Stream Sites

Cordova

Valdez

Whittier

Salmon stream (5)

Positive control (2)

Diesel spill (1)

Salmon Streams Cordova Harbor

PA

H (

ng

/SP

MD

)

103

104

105

106

ER

OD

Ac

tivi

ty (

pm

ol/m

g/m

in)

0

20

40

60

80

100TPAH Chrysenes EROD

*

*(Diesel Spill)

N = 20

PWS 2004: Hatchery Sites

Cordova

Valdez

Whittier

Positive control (2)

Hatchery (5)

Diesel spill (1)

Hatcheries Cordova Harbor

PAH

(ng/

SPM

D)

103

104

105

106

ERO

D A

ctiv

ity (p

mol

/mg/

min

)

0

20

40

60

80

100TPAH Chrysenes EROD

AFK *

AFK *

AFK *

N = 5

PWS 2004: Abandoned Human Activity Sites

Cordova

Valdez

Whittier

Human Activity (5)

Positive control (2)

Diesel spill (1)

Abandoned Sites Cordova Harbor

PAH

(ng/

SPM

D)

103

104

105

106

ERO

D Ac

tivity

(pm

ol/m

g/m

in)

0

20

40

60

80

100TPAH Chrysenes EROD

* McClure

*

*

N = 5

McClure Bay Oiled Pit

Monterey Oil

0

200

400

600

800

1000

1200

1400

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001

Year

Am

ou

nt R

em

ain

ing

(m

^3)

2001 ABL

Oil on PWS Beaches: 1992 – 2001

~25% per YearLoss Rate

Conclusions

Exxon Valdez Oil Remains a Potent CYP1A Inducer

Most Human Activity Sites Are Not

Areawide Sources Are Clearly Not

Remaining EVO May Persist for Decades