A comparison of acute and chronic toxicity methods for marine sediments.
Sublethal test methods are being used with increasing frequency to measure sediment<lb>toxicity, but little is known about the relative sensitivity of these tests compared to the<lb>more commonly used acute tests. A study was conducted to compare the sensitivity of<lb>several acute and sublethal toxicity methods, and investigate their correlations with<lb>sediment chemistry and benthic community condition. Six sublethal methods (amphipod,<lb>Leptocheirus plumulosus 28-day survival, growth and reproduction; polychaete, Neanthes<lb>arenaceodentata 28-day survival and growth; benthic copepod, Amphiascus tenuiremis,<lb>14-day life cycle; seed clam, Mercenaria mercenaria 7-day growth; oyster, Crassostrea<lb>virginica lysosome destabilization; and sediment-water interface (SWI) testing with<lb>embryos of the mussel Mytilus galloprovincialis) and two acute methods (10-day<lb>amphipod survival with Eohaustorius estuarius and Leptocheirus plumulosus) were used<lb>to test split samples of sediment from stations in southern California and San Francisco<lb>Bay. The most sensitive sublethal test, and most sensitive overall, was the life cycle test<lb>with the copepod, Amphiascus. The L. plumulosus 10-day survival test was the most<lb>sensitive of the acute tests. The sublethal tests were not, in general, more sensitive to the<lb>sediments than the acute tests. Of the sublethal tests only the A. tenuiremus endpoints<lb>and polychaete growth correlated with sediment chemistry. There was poor<lb>correspondence between the toxicity endpoints and indicators of benthic community<lb>condition. Differences in test characteristics such as mode of exposure, species-specific<lb>contaminant sensitivity, changes in contaminant bioavailability, and the influence of<lb>noncontaminant stressors on the benthos may have been responsible for the variations in<lb>response among the tests and low correspondence with benthic community condition.<lb>The influence of these factors cannot be easily predicted and underscores the need to use<lb>multiple toxicity methods in combination with other lines of evidence to provide an<lb>accurate and confident assessment of sediment toxicity.