SS4.03 Factors Controlling the Bioavailability and Bioaccumulation of Inorganic and Organic Chemicals into Aquatic Food Chains
Date: Thursday, June 13, 2002
Location: Poster Session - VCC
 
DeBiaseAE, Savannah River Ecology Laboratory, Aiken, USA, debiase@srel.edu
Taylor, B, E, Savannah River Ecology Laboratory, Aiken, USA, taylor@srel.edu
Hinton, T, G, Savannah River Ecology Laboratory, Aiken, USA, hinton@srel.edu
Pinder, J, E, Colorado State University, Ft. Collins, USA, John.Pinder@colostate.edu
 
UPTAKE OF CESIUM BY LITTORAL AND PLANKTONIC INVERTEBRATES IN A SMALL SOUTHEASTERN IMPOUNDMENT
image
Invertebrates constitute the bulk of the primary consumers in most aquatic systems and can thus play an important role in the trophic transfer of contaminants to fish and other secondary consumers. Stable cesium, an analog for radiocesium, was added to Pond 4 on the Savannah River Site, South Carolina, to study short-term (1-2 yr) dynamics of the contaminant, including movement between abiotic and biotic components. The shallow (mean depth=1.6 m) 11-ha impoundment has an extensive, heavily vegetated littoral zone. We measured cesium in the snail Helisoma trivolvis, a littoral consumer, and the dipteran Chaoborus punctipennis, a planktonic predator. Results from the first 3 mo of the experiment (8 sample dates) pointed to the importance of littoral processes for the incorporation of cesium into the biota, beginning with the uptake by periphyton. Concentrations of cesium were an order of magnitude greater in Helisoma than in Chaoborus and five orders of magnitude greater than in filtered pond water. Helisoma and other littoral organisms may serve as primary sources of cesium for fish and other secondary consumers in shallow impoundments.