WHAT ARE WET TESTS?
In whole effluent toxicity (WET) tests, lab-reared aquatic organisms are exposed to various dilutions of effluent for a specific time period, in order to predict at what levels the effluent may cause harm to the organisms (e.g., at what level death, reproductive impairment, or growth inhibition occurs). Test treatments consist of a series of solutions containing different proportions of an effluent sample. A control treatment (an exposure of organisms to dilution water with no effluent added) is used to provide a measure of the acceptability of the test by indicating the quality of the test organisms and the suitability of the dilution water, test conditions, and handling procedures. At the end of the test, the performance (e.g., survival, growth, or reproduction) of the effluent treatments is compared to the performance of the controls to determine whether the effluent had a significant impact on the test organisms. For more information regarding WET testing procedures and requirement
