PT09 Biotic Ligand Model
Exhibit Hall
8:00 AM - Tuesday, 11 November 2003
(PT154) Prediction of acute toxicity of copper in estuaries of the USA using the biotic ligand model.
Arnold, W1, Santore, R2, 1 Copper Development Association Inc., New York, NY, USA2 HydroQual Inc., Camillus, NY, USA
ABSTRACT- The Biotic Ligand Model (BLM) was recently developed and has proved efficient in predicting the acute toxicity of a variety of metals to freshwater organisms. Its utility and strength have resulted in its proposed incorporation into the regulatory framework for calculating water quality criteria for copper in freshwater. In 2000 and 2001, studies were conducted on water samples from San Francisco Bay, California to test the utility of the BLM for predicting copper toxicity to the marine bivalve Mytilus edulis, the most sensitive organism and test in the US EPAs saltwater criteria database. These studies were performed in cooperative effort with regional regulatory authorities, dischargers, and non-government organizations performing water effect ratio tests throughout the North and Central San Francisco Bay. In 2003, studies were conducted using water samples from Puget Sound, Washington, Narragansett Bay, Rhode Island and Galveston Bay, Texas to test the BLMs applicability in estuaries around the USA. In all cases, the application of the model was conducted blind without the modelers prior knowledge of the toxicity test results. The results of this effort indicate that there is a strong predictive relationship between copper toxicity and dissolved organic carbon concentrations of the samples. The BLM demonstrated acceptable predictive capabilities for samples containing dissolved organic carbon between over a wide range of DOC.
Key words: Acute Toxicity, Copper, Biotic Ligand Model, Estuaries