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140730 Battelle Poster SS

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140730 Battelle Poster SS

  1. 1. Validation CORRESPONDENCE: halden@asu.edu #565 RATIONALE The accurate determination of toxicants in surface water and sediments is central to ecological risk assessment. Sampling techniques are therefore designed to determine concentrations of chemicals extant in these matrices. Since ecological risk is tied to the bioavailable mass in sediment and surface water, it may be particularly important to sample the mobile mass in situ. In sediment matrices contaminated with hydrophobic organic contaminants, the mobility of compounds is limited within the pore spaces, where the bioavailable fraction of the compounds reside [1]. Grab sampling and passive sampling techniques have certain drawbacks. Sampling porewater is challenging because grab sampling requires collection of large volumes of wet sediment for centrifugation and subsequent extraction in the lab. Passive sampling techniques do not require collection of any medium, but passive samplers can take days to months to come to equilibrium or adsorb a quantifiable mass of trace analyte [2], particularly when advective transfer to the surface of the sampler is slow, as it is in sediment pore spaces. The sampler developed by the Center for Environmental Security team offers an easy means of sampling both surface water and porewater simultaneously, without the aforementioned drawbacks of grab or passive sampling. OBJECTIVES 1. Design and develop an active sampler that can sample mobile phase pollutants in sediment and surface water. 2. Incorporate the sampler into an analytical method for a suite of hydrophobic organic contaminants, and validate its efficacy. 3. Use the sampler to assess the surface water and porewater concentrations of the selected compounds at an impacted location. ANALYTES Benny Pycke, PhD RESULTS Design and construction Deployment CONCLUSIONS 1. Sub-ppt detection limits are possible with the IS2B. 2. Hydrophobic analyte mass is not significantly lost within the device during sampling. 3. Porewater can be sampled with ease. 4. Results derived using the IS2B are comparable with those derived by coupling grab sampling with in-lab Autotrace extraction. REFERENCES: [1] Suffet et al 1994. Bioavailability. Physical, Chemical and Biological Interactions. [2] Fernandez et al 2012. Environ. Sci & Tech. 1The Biodesign Institute at Arizona State University Center for Environmental Security 781 E. Terrace Road, Tempe, AZ 85287-5904 2The University of Florida College of Medicine Gainesville, FL Active sorbtive sampling for bioavailability: The in situ sampler for bioavailability assessment (IS2B) Samuel Supowit1, Isaac Roll1, Viet Dang2, Kevin Kroll2, Nancy Denslow2, Rolf U. Halden1 Fipronil Fipronil sulfide Fipronil sulfone Fipronil amide Fipronil-desulfinyl Bulk water Pore- water 20 cm Bulk water Pore- water x3x3 x3 x3 x3 Discharge (to bulk water) x3 x3 x3 x1 x1 x1 Manifold Peristaltic pump PW SPE cartridge BW SPE cartridge x3 x3 0 20 40 60 80 100 120 140 Fipronil Fipronil sulfide Fipronil sulfone Fipronil amide Fipronil desulfinyl PercentRecovery(absolute) A B C A B C River Chemical Fipronil -Sulfide -Sulfone -Amide -Desulfinyl Total fipronil A BW IS2B 14.1 ± 3.3 0.61 ± 0.12 4.0 ± 1.3 0.67 ± 0.13 0.04 ± 0.14 19.5 ± 5.0 AT 10.0 ± 0.8 0.22 ± 0.11 3.4 ± 0.5 0.78 ± 0.08 ND 14.4 ± 1.5 PW IS2B** 7.5 ± 1.0 1.4 ± 0.4 3.7 ± 0.7 0.62 ± 0.05 ND 13.2 ± 2.1 AT 5.3 ± 0.2 1.4 ± 0.5 1.9 ± 0.7 0.5 ± 0.1 ND 9.1 ± 1.4 B BW IS2B 5.0 ± 2.5 0.77 ± 0.46 2.3 ± 0.9 1.44 ± 0.66 0.35 ± 0.16 9.9 ± 4.6 AT 3.0 ± 0.1 2.83 ± 1.05 2.2 ± 0.1 2.31 ± 0.23 ND 10.3 ± 1.5 PW IS2B* 5.6 0.94 2.9 2.0 0.25 11.6 C BW IS2B 5.4 ± 0.8 0.81 ± 0.12 3.7 ± 0.9 2.35 ± 0.35 0.06 ± 0.11 12.4 ± 2.3 AT 4.6 ± 0.2 0.83 ± 0.07 3.3 ± 0.1 1.97 ± 0.06 0.03 ± 0.06 10.8 ± 0.5 PW IS2B 4.2 ± 1.4 0.6 ± 0.2 2.9 ± 1.0 1.9 ± 0.5 0.09 ± 0.08 9.7 ± 3.2 1 Estimated. *n=1. **n=2. Else n=3. n=8. Spike = 10 ppt (1 ppt for fipronil-desulfinyl)

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