Use of four microbial tests to assess the ecotoxicological hazard of contaminated sediments

Abstract

Three single-species bioassays (Microtox, Selenastrum capricornutum, and Panagrellus rediuiuus) and a test using microbial communities developed on artificial substrates were used in a series of in situ and laboratory tests evaluating the ecotoxicological hazard of contaminated sediments at two sites on Lake Michigan: Waukegan (Illinois) Harbor and The Chicago Area Confined Disposal Facility Study. In the single-species tests, exposure to elutriates of contaminated sediments significantly inhibited bacterial luminescence, algal photosynthesis, and nematode survival and growth at polluted stations, while elutriates from control stations did not. The battery of three tests is a promising screening tool for in-place pollutants.Protozoan species richness and protozoan phototroph abundance were inhibited by elutriates from contaminated sites, but the abundance of heterotrophic protozoans was enhanced by sediment elutriates from some stations. Microbial community photosynthesis was significantly inhibited by most sediment elutriates, while community respiration was often stimulated; thus, functional responses paralleled the structural changes. Overall, the results of the microbial community tests were consistent with expected patterns of toxicity a t the two sites on Lake Michigan.In general, single-species test results agreed with the community bioassays. Although community tests may be more realistic than single-species bioassays in predicting the impact of sediment contamination on actual ecosystems, caution must be exercised in interpreting the results.

Use of the Ciliated Protozoan Tetrahymena pyriformis for the Assessment of Toxicity and Quantitative Structure–Activity Relationships of Xenobiotics: Comparison with the Microtox Test

“…,scheri, and a eukaryotic model, ¹. pyriformis. The need for a test battery for toxicity assessment was several times evoked (Ross and Henebry, 1989;Clarke et al, 1990;Bitton and Koopman, 1992;Wenzel et al, 1997). Most biomarkers respond speci"cally to a limited number of chemicals (Van Gestel and Van Brummelen, 1996).…”

Wood preservative leachates from docks in an estuarine environment

“…The Microtox bioassay is a sensitive indicator of acute toxicity for a variety of chemical compounds (Bulich 1979;Bulich and Isenberg 1981 ;De Zwart and Sloof 1983;Ross and Henebry 1989;Schiewe et al 1985). For each of the 30 sampling sites, one 0.3-g sediment sample was used to make a series of 12 dilutions ranging from 0.01% to 10% sediment, which were then incubated with cultures of the bioluminescent bacterium Photobacterium phosphoreum for 20 minutes.…”

Assessment of sediment contamination at Great Lakes Areas of Concern: the ARCS Program Toxicity-Chemistry Work Group strategy

“…As a starting point the ARCS --TCWG assessment strategy used a manual from the IJC Sediment Subcommittee (IJC, 1988). Stemming from the expertise of the various TCWG members and from recent research developments (Burton et al, 1989;Giesy & Hoke, 1989;Ross & Henebry, 1989), modifications to the IJC approach were proposed and debated. The final strategy represents a consensus of the group and also reflects external constraints due to limitations of time and financial resources.…”