Bioassay battery

Comparative studies involving toxicity tests abound in the scientific literature. There are many reasons compelling ecotoxicologists to conduct work of this nature, some of which are directed 1) to assess the performance, sensitivity and relevance of individual bioassays undertaken on various chemicals and (liquid and solid) media to specify their scope of use, 2) to optimize the diagnostic potential of bioassay batteries to broaden hazard detection (insure that tests in a battery are complementary and not redundant) and 3) to promote the application of novel assays capable of high throughput for cost-effective screening of (complex) environmental samples. 

INCLUSION OF A FISH TEST IN FUTURE PEEP BIOASSAY BATTERIES... 

Inclusion of a test representative of the fish level of organization in future PEEP bioassay batteries is nevertheless highly advisable owing to the specific adverse effects that liquid wastes can manifest on this trophic level. To offset the constraints mentioned above, appropriate surrogates can now be found with tests conducted with fish cells. Indeed, fish cell bioassays such as those reported in this book (see Chapters 14 and 15, volume 1 of this book) offer reliable and relevant alternatives to whole organism testing that alleviate sample volume and budgetary considerations. 

The pT-index allows the assessment and comparison of the toxic potential of sediments and dredged material. It is one example of an integrated bioassay-battery approach developed for the purpose of environmental management. This sediment assessment index relies on the use of an appropriate battery of bioassays at different trophic levels (decomposers, primary producers, and consumers) allowing the measurement of various types (acute, chronic) and levels (lethal, sublethal) of toxicity. 

In principle, any battery of bioassays can be employed, but small-scale toxicity tests are preferred because of their performance output (Wells et al., 1998). It is highly desirable that bioassays used were part of the initial bioassay battery (prerequisite step) that proved to be sufficiently sensitive in the WASTOXHAS approach. Examples include the Microtox light inhibition test (Vibrio fischeri) and the microalgal growth inhibition assay (Selenastrum capricornutum ) that were found suitable for two tested wastes (see Section 7). 

WASTOXHAS needs essential prerequisites for its optimal operation, namely the initial application of a large bioassay battery conducted after classical small-scale batch shaking leaching test (for example EN 12457-1 to 4, 2002 or equivalent). The final choice of bioassays selected for the battery is not self-evident, but some examples of possible bioassays are given in Table 2 and some concepts are given in Table 3 and Section 3.4. Before undertaking some bioassays, waste pre-treatment may also be required (see Section 7). 

Single species tests and tests using bioassay batteries are called lower-tier tests.19 But in order to carry out a more stringent examination of the complex interactions between potentially toxic chemical compounds and organisms inhabiting specific ecosystems, experiments are sometimes carried out in microcosms and mesocosms the literature describes these as higher-tier tests.19... 

Ma, M., Li, J., and Wang, Z.J. (2005). Assessing the detoxication efficiencies of wastewater treatment processes using a battery of bioassays/biomarkers. Archives of Environmental Contamination and Toxicology 49, 480-487. 

The use of a battery of environmental bioassays for the management of hazardous wastes is applied in the Czech Republic [176]. This battery of environmental bioassays has included representatives of producers, consumers, and destructors D. magna (possible substitution by D. pulex), acute, reproduction, chronic test Scenedesmus quadricauda S. capricomutum), as bottle test or in microwell plates Poecillia reticulate (Danio rerio), acute, chronic, embryolarval tests 5. alba (Lactuca sativa), germination test, 72 hours. 

Lebowitz H, Brusick D, Matheson D, et al. 1979. Commonly used fuels and solvents evaluated in a battery of short-term bioassays [Abstract]. Environ Mutagen 1 172-173. 

In discussing the developments and applications of bioassays to liquid media and to sediments, we have placed some emphasis on the types of chemicals and environmental samples that have been appraised, on the types and frequency of biotic level(s) employed, as well as on the relative use of single species tests as opposed to test battery approaches. 

Of the 75 studies reported in Tables 9 and 10, less than half (n = 34) were conducted with two or more tests representing at least two biotic levels (i.e., test battery approach or TBA), as opposed to those performed with a single biotic level (n = 41). This contrasts somewhat with bioassay applications for liquid media assessment, where TBAs comprised nearly 54% (101/188) of reported studies (Tables 1-3). Again, test and biotic level selection may be based on a variety of... 

Dutka, B.J., Tuominen, T., Churchland, L. and Kwan, K.K. (1989) Fraser river sediments and waters evaluated by the battery of screening tests technique, in M. Munawar, G. Dixon, C.I. Mayfield, T. Reynoldson and M.H. Sadar (eds.), Environmental Bioassay Techniques and their Application Proceedings of the 1st International Conference held in Lancaster, England, 11-14 July 1988, Kluwer Academic Publishers, Dordrecht, Netherlands, pp. 301-315. 

Ferrari, B., Radetski, C M., Veber, A.-M. and Ferard, J.-F. (1999) Ecotoxicological assessment of solid wastes a combined liquid- and solid-phase testing approach using a battery of bioassays and biomarkers, Environmental Toxicology and Chemistry 18 (6), 1195-1202. 

Fochtman, P., Raszka, A. and Nierzedska, E. (2000) The use of conventional bioassays, microbiotests, and some rapid methods in the selection of an optimal test battery for the assessment of pesticides toxicity, Environmental Toxicology 15 (5), 376-384. 

Wilkes, B.D. and Beatty Spence, J.M. (1995) Assessing the toxicity of surface waters downstream from a gold mine using a battery of bioassays, Canadian Technical Report of Fisheries and Aquatic Sciences 2050, 38-44. 

In the Toyama Bay Japanese effluent study, 20% endpoint effect values (e.g., LC20s for the D. magna assay and IC20s for the S. capricomutum assay), which are close approximations of TC values determined from NOEC and LOEC data (as in the Canadian study), were transformed into TU values and integrated into the PEEP formula. In applying the PEEP index concept to a designated series of wastewaters discharging to a common aquatic environment, it is paramount, of course, to use the same battery of bioassays and to report all of their toxicity responses with the same measurement endpoint and statistical analysis system (i.e., TC values for all effluents... 

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