This document describes the development of a novel in situ sampler called the IS2B that can collect time-averaged water and porewater samples to determine trace levels of pollutants. The IS2B uses solid phase extraction cartridges to preconcentrate samples from an engineered wetland over 48 hours. Results showed it could detect fiprole pesticides and metabolites in the low parts-per-trillion range with recoveries of 72-95%. Comparisons to discrete grab samples found the IS2B produced comparable data but represented time-averaged concentrations rather than single time points. The IS2B allows for bioavailability assessments without transporting large sample volumes.

1. Novel Active Sampling Device for Determination of Pollutants in Surface
Water and Porewater – the In Situ Sampler for Bioavailability Assessment
(IS2B)
Samuel D. Supowit1, Isaac B. Roll1, Viet D. Dang2, Kevin J. Kroll2, Nancy D. Denslow2, Rolf U. Halden1
1The Biodesign Institute, Center for Environmental Security, Security and Defense Systems Initiative, Arizona State University, Tempe, AZ 85287
2Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611
Corresponding author: Rolf U. Halden; (P): 480-727-0893; email: Rolf.Halden@asu.edu
Presenting author: Sam D Supowit; (P): 520-245-6576; email: Samuel.Supowit@asu.edu
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2. Rationale for sampler development
Assumption
• What a sampler “sees” is
representative of what
organisms will see.
Challenge
• Many contaminants are
often at trace concentrations
in water and difficult to
detect/quantify.
Solution
• Preconcentration
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Figure 1. Typical deployment of samplers for assessing bioavailability.

3. Rationale
3
Advantages Disadvantages
Discrete grab sampling
• Fast
• Easy
• Temporal trends
• Large volumes of water
• Porewater is difficult
• Sample handling losses
Passive sampling
(SPME, LDPE)
• Time-weighted averages
• Easy to deploy
• Porewater
• Bioavailability
• Method development
• Long sampling periods
• Short term trends??
• Calibration

4. Objectives
• Automatic in situ sampling vs grab sampling
• Quantify at trace levels
• Short sampling period
• Dual phase sampling
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5. Approach
1. Design and build a
sorptive active sampler
for dual-phase sampling
across the sediment-
water interface.
2. Develop an analytical
method incorporating
active sorptive sampling
using SPE as a sample
preparation step.
3. Compare discrete grab
sample data with the
time-averaged data
derived using the active
SPE sampler.
5
SPE cartridges
Dischargeintobulkwater
Pore-
Water
Bulk
water
Qtotal ≤ 0.5 mL/min
Bench extraction of grab sample

6. sulfide
Fipronil
sulfone desulfinyl
amide
Targets
6
Compound
Procambarusa
Hyalella aztecab
Diphetor hagenib 27
OC urban
water conc.
(µg/L)
Half-life
25
LC50 (µg/L)
24
LC50
(µg/L)
24
EC50
(µg/L)
24
LC50
(µg/L)
24
EC50
(µg/L)
28
Silt
loam (d)
29
Facu
conditi
Fipronil 14.3-19.5 1.3-2.0 0.65-0.83 0.20-0.57 0.11-0.21 0.05-0.39 21±0.15
-desulfinyl 68.6 - - - - 0.05-0.13 - 217
-sulfide 15.5 1.1-1.7 0.007-0.003 - - ND >200 195
-sulfone 11.2 0.35-0.92 0.12-0.31 0.19-0.54 0.055-0.13 0.05-0.19 >200 502
a

7. 7
<5 ng/bee
Colony Collapse Disorder?

8. Deployment Location
Engineered Wetland
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9. Deployment Location
Engineered Wetland
9
.

10. Deployment Location
Engineered Wetland
10
.

11. Deployment Location
Engineered Wetland
11
.

12. Results
13
Concept
Design
Fabrication

13. Results
• Analytical QA
Matrix water:
3 L MilliQ water (0.2 L/ch x8)
33 ppm K-citrate
(~ 8 ppm DOC)
300 ppm Kathon ICP-CG
10 ng/L spike
Matrix control signal (x2)
~ 1-10% of matrix spike signal
No isotopically-labeled standards
available.
14
0
20
40
60
80
100
120
140
Fipronil Fipronil sulfide Fipronil sulfone Fipronil amide Fipronil desulfinyl
AbsoluteRecovery(%)
10 ng/L spike (1 ng/L for fipronil-desulfinyl)

14. Results
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Table 1. Calculated fiprole MDLs and LOQs using the IS2B for preconcentration (n = 7).
Chemical MDL (ng/L) LOQ (ng/L) Recovery Stdev
Spike
(ng/L)
Fipronil 0.74 2.37 92% 24% 1
-sulfide 0.69 2.20 93% 22% 1
-sulfone 0.41 1.21 86% 9% 1
-amide 0.84 2.69 77% 12% 1
-desulfinyl 0.041 0.13 95% 13% 0.1
• Analytical QA
Chemical MDL (ng/L) LOQ (ng/L) Recovery Stdev Spike (ng/L)
Fipronil 0.85 2.69 72% 27% 1
-sulfide 0.72 2.30 87% 23% 1
-sulfone 0.98 3.13 87% 31% 1
-amide 0.77 2.45 93% 25% 1
-desulfinyl 0.048 0.15 74% 15% 0.1
Table 2. Calculated fiprole MDLs and LOQs using the Autotrace for preconcentration (n = 7).

15. Results
16
0
5
10
15
20
25
30
A B C
Totalfiproleconcentration(ng/L)
Bulk water
A B C
Porewater
IS2B (time averaged 48 hr composite)
Autotrace (discrete grab sample)
vs

16. Results
17
Bulk water concentrations
0
2
4
6
8
10
12
14
16
18
20
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0
1
2
3
4
5
6
0
1
2
3
0.00
0.10
0.20
0.30
0.40
0.50
0.60
Concentration(ng/L)
IS2B (48 h avg) Autotrace (Single grab sample)
A B C A B C A B CA B C
Fipronil -Sulfide -Sulfone -Amide -Desulfinyl
A B C
MDL

17. A B C
0
2
4
6
8
10
A B C A B C A B CA B C
Results
18
0.0
0.5
1.0
1.5
2.0
0
1
2
3
4
5
0
1
2
3
0.00
0.05
0.10
0.15
0.20
0.25
0.30
Concentration(ng/L)
Fipronil -Sulfide -Sulfone -Amide -Desulfinyl
Porewater concentrations (IS2B)

18. Points to Take Home
Sampler capabilities and performance
• Dual phase sampling
• Good recovery
• pg/L LODs
• Potential bioavailability assessment
• No large volume sample transport
• Data produced comparable to conventional methods
• Time averaged data
• Short sampling periods
Wetland demonstration
• High contaminant mobility
• Little partitioning (~1% TOC in sediment)
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19. Acknowledgments
• Principal Investigator Dr. Rolf Halden, PE
• Isaac Roll, EIT, MSE (designs)
• Dr. Benny Pycke
• Tengfei Chen
• Dr. Nancy Denslow
• Dr. Viet Dang
• Kevin Kroll
• National Institutes of Health
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