PARENT SESSION
PW11 - Site-Specific Risk Assessments
Wednesday, 20 November 2002
8:00 AM to 6:30 PM
Exhibit Hall
(P852) Ecological Risk Assessment of Sediment and Bile Contaminants at Areas of Concern in Lake Erie.
Passino-Reader, Dora*,1, Smith, Stephen2, Baumann, Paul3, Blazer, Vicki4, Nelson, Scott1, Rasolofoson, Allain1, 1 USGS Great Lakes Science Center, Ann Arbor, MI, USA2 USGS National Center, Reston, VA, USA3 USGS Ohio State University, Columbus, OH, USA4 USGS Leetown Science Center, Kearneysville, WV
ABSTRACT- Lake Erie Ecological Investigations (LEEI) evaluated contaminants in sediments at Areas of Concern (AOCs) and reference sites in the Lake Erie basin of the Laurentian Great Lakes. In addition, we measured PAH metabolites in bile of fish collected at the same sites. We applied ecological risk assessment techniques to identify those contaminants posing a potential risk to the aquatic biota. Probability distributions were selected based on variability of residue concentrations across the sites. We conducted Monte Carlo simulations to quantitate uncertainty and estimate the probability of threshold (TEC) and probable effects (PEC) exceedences. The certainty of exceeding Threshold Effects Concentration (TEC) guidelines was >50% for total PAHs, seven PAHs including benzo(a)pyrene, total DDTs, As, Cu, Hg, Ni, Pb, and Zn. Exceedences were generally higher at the Ashtabula River, OH; Cuyahoga River, OH; Ottawa River, OH; and Detroit River, MI. BaP and NAPH metabolites in brown bullhead bile were highest at Cuyahoga River and Buffalo River. Internal and external fish health measurements on brown bullhead were assessed against sediment and bile contaminants. Sediment contaminant levels and incidence of abnormalities in brown bullhead have generally decreased at the Black River, OH, since remediation. Assessment endpoints and probabilistic risk approaches developed in this investigation can be applied to AOCs throughout the Great Lakes and other aquatic areas.
Key words: Great Lakes, ecological risk assessment, contaminated sediments, Monte Carlo