|HOME SCHEDULE AUTHOR INDEX SUBJECT INDEX|
(425) Bioaccumulation of Metals and Explosives from Soil into Earthworms – A Risk Assessment Case Study.
Kierski, Michael*,1, Frank, John1, Ferguson, Elizabeth2, 1 MWH, Madison, WI, USA2 United States Army Corps of Engineers, Louisville, KY
ABSTRACT- At the Open Burning Ground (OBG) at the Savanna Army Deport Activity (SVDA) located in northwestern Illinois, MWH is conducting an ecological risk assessment (ERA) on behalf of the Department of the Army. As part of a screening level ERA (SLERA) performed, it was estimated that earthworm consumption by either the shrew or American robin might pose a potential ecological concern. Earthworm bioaccumulation bioassays were performed on a site-specific basis to measure the amount of accumulation of metals and explosives in earthworms. This data was used to refine the previous estimates of risk for vermivores. A total of 24 investigative and 6 reference area soil samples were run through a 28-day earthworm bioaccumulation bioassay using ASTM Method E1676-97. The earthworms were then analyzed for metals (USEPA Method 6010B) and explosives (USEPA Method 8330). The soil samples were analyzed for metals, explosives, and a number of soil properties. Nineteen of 23 target analyte (TAL) metals were detected in most of the 71 samples of earthworms exposed to investigative soils. Antimony, beryllium, selenium, and thallium were detected very infrequently in earthworm samples. Bioaccumulation factors (BAF)s for individual analytes were plotted against their soil concentrations to determine if the BAF was concentration dependent. The magnitude of bioaccumulation for a number of the metals was concentration dependent. The BAFs for some of the metals estimated from the bioaccumulation bioassay were much higher than those used in the SLERA, and thus for these metals the risk estimates were higher than previously estimated. Explosives BAFs were generally much lower than those based on reference sources used in the SLERA resulting in lower risk estimates.
Key words: bioaccumulation, earthworm, explosives, metals
Internet Services provided by|
Allen Press, Inc. | 810 E. 10th St. | Lawrence, Kansas 66044 USA
e-mail firstname.lastname@example.org | Web www.allenpress.com
All content is Copyright © 2002 SETAC