Devices and methods for determination of bioavailability of pollutants

Patent metadata

Field	Value
Publication number	US-9683921-B2
Application number	US-201214112711-A
Country	US
Kind code	B2
Filing date	Apr 17, 2012
Priority date	Feb 8, 2010
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

Contaminant mass collection in saturated sedimentary environments for bioavailability determination. A casing includes a screen between the environment that is subject to sampling, such as a saturated sediment and the device itself. The casing includes a water intake zone, a pump, and sorptive media. The water intake zone, the pump, the screen and the sorptive media, are all operably linked in sequence. The screened casing is secured to form an in situ device; the screen is in fluid communication with the water intake zone and excludes endemic sediments and aquatic life. The in situ device is deployed in the saturated sedimentary environment. The pump operates to concentrate analytes from the selected environment in the sorptive media, where the concentrated analytes include the analyte mass of time-weighted fluid samples.

First claim

What is claimed is:

1. A method for contaminant mass collection in saturated sedimentary environments for bioavailability determination, the method comprising:
securing a screen casing around a shell to form an in situ device, where the screen casing provides a permeable interface between a sampled environment and the shell;
installing a first water intake within the screen casing, where the screen casing is in fluid communication with the first water intake;
installing a second water intake within the casing, where the second water intake is vertically spaced apart from the first water intake;
coupling at least one multi-channel pump to pump water flowing through the first water intake and the second water intake through separate pump channels;
coupling sorptive media to receive water from the at least one multichannel pump;
where the water includes a sample environment having bulk water at a first layer and sediment pore water at a second layer, deploying the first water intake in the first layer and the second water intake in the second layer; and
operating the pump to draw bulk water from the first water intake and to draw pore water from the second water intake, simultaneously or sequentially, for a series of specified time increments to arrive at a time-averaged concentration of analytes from the first layer and the second layer of the sampled environment in the sorptive media, where the concentrated analytes include the analyte mass of time-weighted fluid samples.

2. The method of claim 1 wherein the sorptive media are contained in at least two extraction cartridges which are connected in series or parallel to one or more outputs of the pump.

3. The method of claim 1 wherein deploying the in situ device comprises vertically deploying the in situ device.

4. The method of claim 3 wherein vertically deploying the in situ device comprises using direct-push deployment or augering.

5. The method of claim 1 further comprising first filtering the water entering the device.

6. The method of claim 1 wherein the sorptive media is selected to simulate uptake of pollutants into biological organisms.

7. The method of claim 1 wherein operating the pump to concentrate analytes includes collecting depth-discrete samples from pore water corresponding to saturated sediments in the sampled environment.

8. The method of claim 7 including time-averaged collection of said samples over arbitrary periods of time, and analysis of transport phenomena.

9. The method of claim 2 wherein deploying the in situ device comprises placing the in situ device in a saturated sediment within the sampled environment until interstitial water between the screen and the casing of the in situ device is in equilibrium with the pore water of the saturated sediment, and activating the pump to pass the water through the sorptive media.

10. The method of claim 9 including operating the pump continuously at flow rate so that withdrawn water is replaced in the interstitial volume by pore water.

11. The method of claim 9 including operating the pump intermittently so as to pass the entire volume of the interstitial water through the extraction cartridges.

12. The method of claim 1 wherein the concentrated analytes includes a concentration of pollutants affecting sediment-dwelling biota.

13. The method of claim 1 further comprising measuring a contaminant ratio of bulk water to pore water.

14. The method of claim 13 further comprising determining of pollutant concentrations in pore water and pollutant concentrations in bulk water combined with analyzing of resident, sediment dwelling biota and resident bulk-water dwelling biota; and calculating approximate pollutant concentrations in biota living in sediment and bulk water, respectively.

15. The method of claim 13 further comprising predicting a level of exposure for organisms in contact with both bulk water and sediment pore water by computing an additional bioaccumulation factor to predict their level of exposure and body burden.

16. The method of claim 1 wherein pore water taken into the in situ device is fractionated into (i) unfiltered pore water, (ii) filtered pore water, and (iii) ultra-filtered, colloid-depleted pore water.

17. The method of claim 1 further comprising using selected extraction resins in parallel to extract contaminant groups from the water including ionic and non-ionic analytes.

18. The method of claim 17 further comprising elution of the extracted contaminant groups followed by toxicity assays.

19. The method of claim 1 wherein the screen casing is a mesh sleeve.

Assignees

• Halden Rolf U
• Roll Isaac B
• Univ Arizona State

Inventors

• Halden Rolf U
• Roll Isaac B

Classifications

• E02D1/06

  Sampling of ground water · CPC title

• G01N5/02

  by absorbing or adsorbing components of a material and determining change of weight of the adsorbent, e.g. determining moisture content {(absorption bulbs B01D53/00)} · CPC title

• G01N1/405 Primary

  by adsorption or absorption · CPC title

• B01D15/14

  relating to the introduction of the feed to the apparatus · CPC title

• B01D53/025

  with wetted adsorbents; Chromatography (analytical chromatography G01N30/00 - G01N30/96; for liquids B01D15/08) · CPC title