You are here:
An interlaboratory comparison of sediment elutriate preparation and toxicity test methods
Citation:
Haring, H. J., M. E. Smith, J. M. LAZORCHAK, P. CROCKER, A. EURESTI, K. A. BLOCKSOM, M. C. Wratschko, AND MICHAEL SCHAUB. An interlaboratory comparison of sediment elutriate preparation and toxicity test methods. ENVIRONMENTAL MONITORING AND ASSESSMENT. Springer, New York, NY, 184(12):7343-7351, (2012).
Impact/Purpose:
Proposed research will provide environmental science and risk assessment communities with advanced molecular biological indicator methods, complete with validation studies and guidance for their application.
Description:
Elutriate bioassays are among numerous methods that exist for assessing the potential toxicity of sediments in aquatic systems. In this study, interlaboratory results were compared from 96-hour Ceriodaphnia dubia and Pimephales promelas static-renewal acute toxicity tests conducted independently by two laboratories using elutriate samples prepared from the same sediment. The goal of the study was to determine if the results from the elutriate tests were comparable between two U.S. Environmental Protection Agency (USEPA) laboratories when different elutriate preparation procedures were employed by each lab. Complete agreement in site characterization was attained in 22 of the 25 samples for both bioassays amongst each lab. Of the 25 samples analyzed, ten were found to be toxic to at least one of the species tested by either laboratory. The C. dubia elutriate tests conducted by the National Exposure Research Laboratory (NERL) indicated seven of the 25 sediment samples were toxic, while eight sediment samples were characterized as such in testing conducted by USEPA Region 6. The P. promelas elutriate tests conducted by NERL determined eight samples as toxic, while Region 6 tests displayed toxicity in five of the samples. McNemar's test of symmetry for C. dubia and P. promelas tests indicated no significant differences in designating a site toxic between NERL and Region 6 laboratories. Likewise, Cohen's kappa test revealed significant agreement between NERL and Region 6 C. dubia and P. promelas elutriate tests. The authors conclude that differences in interlaboratory elutriate preparation procedures have no bearing on the ability of either the C. dubia or P. promelas bioassay testing methods to detect toxicity, while yielding similar results.
