Related In-house Publications
Aquatox Research staff actively engage in professional
activities related to the presentation of study results either
in a generic fashion or with the approval of study sponsors.
The citations listed below reflect a minor portion of the
activities of Aquatox Research staff in the area of Microtox testing. Full
reprints of each of these publications are available upon request.
A bibliography of hundreds of Microtox related publications
is available for downloading from the AZUR Environmental/Strategic Diagnostics website.
A Review of the Microtox® Toxicity Test System for Assessing the Toxicity of Soils and Sediments (Abstract Only)
F.G. Doherty. 2001. Water Qual. Res. J. Canada 36:475-518
Use of Microtox for screening sediment or soil samples from contaminated systems either singly or in combination with a battery of other tests is supported by an ever-increasing number of comparative studies demonstrating its utility, sensitivity, rapidity, and affordability. Organic-solvent extracts and direct solid phase material provide an assessment of the potential toxicity exerted by both dissolved and bound contaminants. In contrast, tests utilizing pore water or elutriates may be limited to assessing the contribution of dissolved contaminants only. Each approach is limited in the scope of its applications.
The apparent toxicity of elutriates can be a function of extraction solvent and overall procedure. The apparent toxicity of solid phase samples is influenced by sample color and composition; more specifically, the ratio of clay to silt. However in general, the results obtained through in-laboratory testing with the Microtox Test System are often consistent with the results of both sediment invertebrate in-laboratory toxicity tests and macroinvertebrate field surveys. There is also evidence that toxicity assessments obtained with the Microtox Test System are related to analytically-derived concentrations of certain classes of contaminants.
Comparison of the Ceriodaphnia dubia and Microtox® Inhibition Tests for Toxicity Assessment of Industrial and Municipal Wastewaters (Abstract Only)
F.G. Doherty, A.A. Qureshi, and J.B. Razza. 1999. Environ. Toxicol 14:375-382
Toxicity tests on effluents from industrial production facilities, municipal and industrial wastewater treatment plants, and stormwater runoff were conducted with the freshwater invertebrate, Ceriodaphnia dubia and the marine luminescent bacterium, Vibrio fischeri in the MicrotoxR,1 Test System. Percent mortalities of C. dubia in whole effluent, generated in 24- and 48-hour exposure periods during the conductance of static-renewal acute and chronic tests were compared with percent reductions in light output by V. fischeri after 15-min exposure periods in the Microtox Inhibition Test. A total of 16 effluent and stormwater samples from seven sources were used in tests conducted over a three-month period. Results of the Microtox Inhibition tests correctly predicted the results of C. dubia tests for all eight non-toxic samples after both 24- and 48-hour exposure periods. Of three samples that were toxic to C. dubia within 24 hours, the Microtox test also detected toxicity in two of those samples. Results from tests on the remaining five samples showed that while the Microtox Inhibition test indicated the presence of toxic components after 15 minutes exposure, C. dubia required exposure to potentially toxic samples for 48 hours before producing a toxic response.
Biomonitoring Includes Both Traditional and Alternative Tests
F.G. Doherty. 1996. Clearwaters 26(3):39-40
Despite its mysterious "black box" reputation with the layman, environmental scientists have engaged in toxicity testing activities in one form or another (single chemicals vs. complex mixtures) since at least the early 1900s. This nearly century-long record of experience has allowed the current generation of aquatic toxicologists to devise test protocols that address a variety of levels of focus ranging from short-term or acute to long-term or chronic toxic effects on populations of single species, communities composed of several species, or entire ecosystems. The most common toxicity tests are those employing a limited number of individuals from the same species to assess the potential toxicity of a complex effluent on organisms in a surface body of water.