Order this information in Print

Order this information on CD-ROM

Download in PDF Format

     

Click here to make tpub.com your Home Page

Page Title: CONCLUSIONS
Back | Up | Next

Click here for a printable version

Google


Web
www.tpub.com

Home


   
Information Categories
.... Administration
Advancement
Aerographer
Automotive
Aviation
Combat
Construction
Diving
Draftsman
Engineering
Electronics
Food and Cooking
Math
Medical
Music
Nuclear Fundamentals
Photography
Religion
USMC
   
Products
  Educational CD-ROM's
Printed Manuals
Downloadable Books
   

 

ERDC TN-DOER-R3
September 2004
supported by the fact that only one organic compound was identified (BBF) for which both
plants and worms showed significant transfer from the DM mixtures.
CONCLUSIONS: Results of this study revealed the following:
Perennial ryegrass responded to increasing levels of Arochlor-1248, PAHs, and various
metal contaminants in DM mixtures by exhibiting increased bioaccumulation and
toxicity.
Substrates with an IHC-DM contribution exceeding 33 percent did not support plant
growth. This may indicate that this plant species may be too sensitive to project organics
bioaccumulation from DM, containing both organics and high levels of metals.
Perennial ryegrass may be used for bioaccumulation of (selected) PAHs at lower metals
levels, e.g. for beneficial use of DM, in North America.
10
Log-transformed PAH concentrations on a plant-lipid basis were accurate predictors of
10
log-transformed PAH concentrations on a DM-organic carbon basis for 6 of the 16
PAHs (i.e. FLU, PHE, FLA, PYR, BAA, and BBF), but not for PCBs.
Earthworms also showed an increased bioaccumulation and decreasd biomass in response
to increasing levels of Arochlor-1248, PAHs, and metals contamination. Because the
worms survived on all DM mixtures, they may be considered as tolerant enough to
project organics bioaccumulation from DM, containing both organics and high levels of
metals.
The earthworms were just as reliable in accumulating PAHs as the plants, but for
different compounds.
10
Log-transformed PAH concentrations on a worm-lipid basis were accurate predictors of
10
log-transformed PAH concentrations on the DM-organic carbon basis for 6 of the 16
PAHs (i.e. ACE, FLA, BBF, IND, and BGHI), but not for PCBs.
C18 disks were reliable devices to project potential bioavailability of almost all organics
present; i.e. for 14 of the 16 PAHs (ACY, ACE, FLU, PHE, ANT, FLA, PYR, BAA,
CHR, BBF, BKF, BAP, IND, BGHI, DIB) and for Arochlor-1248.
Plant and earthworm bioaccumulation may be Tier III and valid Tier IV assay (Upland
Testing Manual 2003), provided more work is done on the bioavailability and selectivity
of metal-tolerant, test organisms for organics, and on the desorption and mobility of
organics in sediments and soils. C18 disks certainly look promising.
POINTS OF CONTACT: This technical note was written by Dr. Elly P.H. Best, (601) 634-
4246, . Questions regarding this technical note should be
directed to Dr. Best or the manager of the Dredging Operations and Environmental Research
Program, Dr. Robert M. Engler (601) 634-3624, ). This
technical note should be cited as follows:
Best, E.P.H., Geter, K., Tatem, H.E., Fredrickson, H.L., Richmond, M., Furey, J., and Wells, M.
(2004). "Validation of pathway analysis of organic contaminants from aged dredged material
using plants and worms," DOER Technical Notes Collection (ERDC TN-DOER-R3), U.S. Army
Engineer Research and Development Center, Vicksburg, MS. www.wes.mil/el/dots/doerc...pdf.
11

Privacy Statement - Press Release - Copyright Information. - Contact Us - Support Integrated Publishing

Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business