Bioassay aquatic invertebrates

Anderson, B.G. Aquatic invertebrates in tolerance investigations from Aristotle to Naumann. In Aquatic Invertebrate Bioassays Buikema, A.L. Jr., Caims, J. Jr., Eds. American Society for Testing and Materials Philadelphia, PA, 1980 Vol. 3, 3-35. 

Damasio J, Tauler R, Teixido E, Rieradevall M, Prat N, Riva MC, Soares AMVM, Barata C (2008) Combined use of Daphnia magna in situ bioassays, biomarkers and biological indices to diagnose and identify environmental pressures on invertebrate communities in two Mediterranean urbanized and industrialized rivers (NE Spain). Aquat Toxicol 87 (4) 310-320... 

Most commonly, bioassays for the evaluation of the acute toxic effects of pesticides are based on single aquatic species selected to be representative of a range of taxonomic and functional groups, i.e., bacteria, algae, invertebrates or fish [ 53,54]. Generally, toxicity evaluation using a single species is the alternative of choice rather than the use of multiple species, because extrapolation of effects to an ecosystem is more difficult and can often lead to incorrect conclusions. 

Invertebrate species have been widely used in toxicity studies of pesticides [61]. Zooplankton play a key role in the food chain because they occupy a central position. Therefore, their responses to natural and anthropogenic stresses are intimately linked with other food predator organisms. The most widely accepted bioassays employ species such as Ceriodaphnia dubia, Daphnia magna, Artemia salina, or Thamnocephalus platyurus [62-64]. D. magna has been used for many years as a standard aquatic test species and formally endorsed by the major international organizations such as the EEC, OECD, and ASTM [65-67]. Its choice is mainly because it represents the zooplankton community and is a species of worldwide occurrence. In addition, it has a greater sensitivity to toxicants, particularly pesticides, compared with other aquatic species [61,68] (Table 1). 

One of the factors supporting the use of algae and invertebrates in the bioassays is their niche in aquatic ecosystems. If these organisms are adversely affected by a toxicant, then the surrounding ecosystem may also feel the effects, either directly or indirectly, from the lack of a food source. Algae and invertebrates occupy low trophic levels, and their disturbance may exhibit a chain effect throughout the ecosystem. 

For environmental testing, bioassays provide an integrated picture of the overall toxicity of pore water, sediment elutriate or sediment from a contaminated site. Various aquatic organisms, such as vertebrates, invertebrates, protozoa, algae, macrophytes and bacteria are used to test environmental samples. The idea behind these toxicity tests is that the test organisms will react in a predictable way to various types of environmental contaminants. 

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