Response of Juvenile Rainbow Trout to Pesticides in Surface Waters within Urban

Streams in Western Washington

Christie Shavey

Sara Bogard, Jacki Bricker, Erin Lowery, Cara MenardUniversity of Washington, School of Aquatic and Fishery Sciences

FISH 455 / ESC 457

Cat Curran Martin Grassley Chris GrueUniversity of Washington, Washington Cooperative Fish and Wildlife Research Unit

Pesticide Usage

• Pesticide Concentrations in Surface Waters

• Salmonids

• Acetylcholinesterase (AChE)

• Organophosphates

• Carbamates

Objective:

To determine effects of a chemical cocktail representative of that reported in storm waters flows in Western Washington on brain acetylcholinesterase activity, behavior and survival of juvenile rainbow trout (Oncorhynchus mykiss)

Endpoints:

•Mortality

•Behavior

•Changes in AChE activityPhoto by M. Lorenzoni

Chemical Cocktail

Name Nominal Concentration (ppb)Atrazine 0.022,4-D 3.30Dicamba 0.09Dichlobenil 0.54MCPA 0.38MCPP 0.77Prometon 0.19Simazine 4.99Triclopyr 2.70Carbaryl 0.21Diazinon 0.43Malathion 0.22Pentachlorophenol 0.134-nitrophenol 0.29

Maximum Concentration Values

Available Products at Retail Stores

Photo by M. Grassley

Photos by M. Grassley

Testing

Two Tests Conducted:

Replicates of 10 / concentration

Test 1:

• Control & 1x original chemical cocktail

• n = 20

Test 2:

• Control, 1x, 3.3x & 10x original chemical cocktail

• n = 10

Testing

•Followed U.S. EPA Protocols for Static 96-hour Toxicity Tests

•Fish Loading: 1.25 L / g

•Average Fish Length / Weight

Test 1: Length 9.7 cm / Weight 10.38 g

Test 2: Length 9.8 cm / Weight 10.62 g

Environmental Chamber

Photos by M. Grassley

Methods

Fish Behavior

Water Quality

Photos by M. Grassley

Actual Chemical Concentrations

Photos by M. Grassley

Methods

Brain Assay

Treatment n Temp (°C) DO (mg/L) pHConductivity

(µS)

Test 1 Control 20 12.7 ± 0.7 9.27 ± 0.5 6.75 ± 0.2 70.4 ± 4.0

1X 20 12.7 ± 0.6 9.00 ± 1.0 6.88 ± 0.1 71.0 ± 4.9

Test 2 Control 10 12.62 ± 1.6 9.96 ± 0.77 6.94 ± 0.73 75.22 ± 4.6

1X 10 12.66 ± 2.0 10.07 ± 0.95 7.03 ± 0.6 75.68 ± 5.6

3.3X 10 13.10 ± 1.6 9.75 ± 1.72 7.00 ± 0.44 74.68 ± 4.0

10X 10 12.69 ± 2.0 9.76 ± 2.66 6.97 ± 0.68 75.77 ± 6.2

Water Quality Data Results

Meets EPA requirements:

Temp: 12 ± 2oC

DO: ≥5 mg/L

pH: 6 - 8

O2

O2

O2

Brain Cholinesterase Results – Test 2

0

20

40

60

80

100

120

Control 1x 3x 10x

Treatment

Per

cen

t o

f C

on

tro

l

106%

16%

77%

AChE Activity in Juvenile Rainbow Trout Exposed to Chemical Cocktail

Key: Active; Lethargic; Dead

Fish Behavior Results – Test 2P

erce

nt R

espo

ndin

g

Control

0

20

40

60

80

100

6 hr 24 hr 48 hr 72 hr 96 hr

Chemical 1X

0

20

40

60

80

100

6 hr 24 hr 48 hr 72 hr 96 hr

Chemical 3.3X

0

20

40

60

80

100

6 hr 24 hr 48 hr 72 hr 96 hr

Chemical 10X

0

20

40

60

80

100

6 hr 24 hr 48 hr 72 hr 96 hr

Interpretations

• Maximum Concentrations ↔ Concentrations in Streams

• Brain Cholinesterase Inhibition:

1x = No

3.3x & 10x = Yes

• Fish Behavioral Effects

0

2

4

6

8

10

12

14

16

0.13

10.

393

0.65

50.

917

1.17

91.

441

1.70

31.

965

2.22

72.

489

2.75

13.

013

3.27

5

Concentration (ppb)

Fre

qu

en

cy

2,4-D Unfiltered

Geometric Mean = 0.206 ppb

95% CI = 0.145 – 0.295

Maximum 3.30 ppb

0

2

4

6

8

10

12

14

16

Concentration (ppb)

Fre

qu

ency

Geometric Mean = 0.022 ppb

95% CI = 0.016 – 0.029

Prometon Filtered

Maximum 0.19

Name 1x Concentration LC50 (ppb)Atrazine 0.02 4,000 (18,000-32,000)

2,4-D 3.30 >100,000Dicamba 0.09 28,000Dichlobenil 0.54 6,260 (4,680-8,370)

MCPA * 0.38 >10,000MCPP 0.77 124,800Prometon 0.19 20,000Simazine 4.99 >100,000Triclopyr 2.70 >100,000Carbaryl 0.21 1,950 (1450-2630)

Diazinon 0.43 90Malathion 0.22 200 (160-240)

Pentachlorophenol 0.13 115 (108-122)

4-nitrophenol 0.29 3,800

LC50 Values for Rainbow Trout

* Indicates different species

If this is the case…

Why did we see mortality?Why did we see mortality?

Chemical Interactions

2.1 ppbCarbaryl

4.3 ppbDiazinon

2.2 ppbMalathion

84% Inhibition or Mortality

Synergism &/or Potentiation

Summary

• No brain inhibition at 1x

• Brain inhibition of 23% at 3.3x & 84% at 10x

• Apparent change in behavior at 1x, 3.3x & 10x

• Potential chemical interactions resulting in brain cholinesterase & mortality

• Concentrations tested were 1-2 orders of magnitude greater than average field concentrations

Future Research

• Chemical interactions

• Survival & reproduction of adult coho

Acknowledgements

We thank the USGS Cooperative Units Program, the School of Aquatic and Fishery Sciences and the Washington Cooperative Fish and Wildlife Research Unit.

The unit is financially supported by the USGS, University of Washington, Washington State University and the Washington Departments of Ecology, Fish and Wildlife, and Natural Resources.

We also thank Windy Madsen for help with the toxicity tests and cholinesterase assays.