Acute aquatic tests duration

Acute aquatic tests duration, 133 species selection, 133 Advisory function of QAU, 114 Agricultural chemicals residue field trials program, quality assurance, 99-106... 

Toxicity tests are necessary tools to evaluate the concentration and duration of exposure of a chemical required to produce certain adverse effects. Molecular processes directly affected by the exposure to the chemical agent are the most liable criterions. Nevertheless, these effects are difficult to detect in aquatic toxicology because the processes are generally not well understood [72], Alternatively, other end points which fulfil the necessary requirements, namely the need to be unequivocal, relevant, easy to observe, describe and measure, biologically significant and repeatable, are used. These include measures of mortality, which is frequently employed in the early evaluation of the toxicity of a pollutant in acute toxicity tests. This criterion allows comparison of toxicity exerted by chemical agents with very different mechanisms of action. 

No studies on the acute toxicity of C12LAS to algae and aquatic plants were found in the literature. Typical toxicity-testing protocols use a test duration of 4-7 days. This duration of testing represents a significant portion of the organisms life span for the taxa tested. Thus these toxicity tests are appropriately considered chronic-toxicity tests. 

There are two basic types of aquatic single-species toxicity tests acute and chronic. Acute toxicity tests have been the workhorse of aquatic toxicologists for many years. These tests are relatively simple, take little time, and are cost-effective. A large historical database exists for many chemicals and effluents. Acute toxicity tests are most often used to quickly screen toxicity or to determine the relative sensitivities of different test species. Mortality is the effect monitored during the test duration of 48 h (invertebrates) or 96 h (fish). In a typical acute toxicity test, 5-10 organisms are exposed under static conditions in glass test beakers to five test concentrations. A control is included. The experiments with test concentrations and control are conducted in triplicate. Daily observations are made on survival, and dead organisms are removed. 

Moore DW, Schluchter MD, Scott GI. 1990. Use of hazard models in evaluating the effect of exposure duration on the acute toxicity of three pesticides. In Landis WG, Van der Schalie H, editors. Aquatic toxicology and risk assessment. Volume ASTM STP 1096. Philadelphia (PA) American Society for Testing and Materials, p 247-263. 

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