Development and Application of a Sublethal Toxicity Test to PAH Using Marine211 Harpacticoid Copepods

摘要

This research project was designed to improve our understanding of the acute and211u001esublethal effects of PAHs to benthic invertebrates. Sublethal bioassay protocols 211u001efor benthic harpacticoid copepods were developed, and two species of 211u001eharpacticoids were exposed to a range of concentrations of sediment-amended PAHs; 211u001ethe single compounds fluoranthene and phenanthrene as well as a complex mixture 211u001e(diesel fuel). The harpacticoid copepods Schizopera knabeni and Nitocra lacustris 211u001ewere tested using several bioassay approaches. Reproductive assays, feeding 211u001eassays and avoidance tests were conducted in addition to lethal tests for S. 211u001eknabeni. Species-specific differences in sensitivity were detected. Early life 211u001ehistory stages were much more sensitive than adults in one species but not in the 211u001eother. Concentrations of PAH as low as 26 micrograms PAH decreased copepod 211u001eoffspring production, egg hatching success, and embryonic and early-stage 211u001edevelopment, demonstrating the high sensitivity of life history-related 211u001eendpoints. In addition, grazing on microalgae was significantly impaired at 211u001econcentrations as low as 20 micrograms/g PAH after short exposures (<30 h). 211u001eFinally it was demonstrated that harpacticoids can actively avoid contamination.